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1
Roitberg, B. D., G. Boivin, and L. E. M. Vet. "Fitness, parasitoids, and biological control: an opinion." Canadian Entomologist 133, no. 3 (June 2001): 429–38. http://dx.doi.org/10.4039/ent133429-3.
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AbstractFitness, defined as the per capita rate of increase of a genotype with reference to the population carrying the associated genes, is a concept used by biologists to describe how well an individual performs in a population. Fitness is rarely measured directly and biologists resort to proxies more easily measured but with varying connection to fitness. Size, progeny survival, and developmental rate are the most common proxies used in the literature to describe parasitoid fitness. The importance of the proxies varies between papers looking at evolutionary theories and those assessing ecological applications. The most direct measures of fitness for parasitoids are realised fecundity for females and mating ability for males, although these proxies are more difficult to measure under natural conditions. For practical purposes, measure of size, through body size or mass, is the proxy easiest to use while providing good comparative values; however, care must be taken when using a single proxy, as proxies can be affected differently by rearing conditions of the parasitoid.
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Yusa, Yoichi, Mai Yoshikawa, Jun Kitaura, Masako Kawane, Yuki Ozaki, Shigeyuki Yamato, and Jens T. Høeg. "Adaptive evolution of sexual systems in pedunculate barnacles." Proceedings of the Royal Society B: Biological Sciences 279, no. 1730 (August 31, 2011): 959–66. http://dx.doi.org/10.1098/rspb.2011.1554.
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How and why diverse sexual systems evolve are fascinating evolutionary questions, but few empirical studies have dealt with these questions in animals. Pedunculate (gooseneck) barnacles show such diversity, including simultaneous hermaphroditism, coexistence of dwarf males and hermaphrodites (androdioecy), and coexistence of dwarf males and females (dioecy). Here, we report the first phylogenetically controlled test of the hypothesis that the ultimate cause of the diverse sexual systems and presence of dwarf males in this group is limited mating opportunities for non-dwarf individuals, owing to mating in small groups. Within the pedunculate barnacle phylogeny, dwarf males and females have evolved repeatedly. Females are more likely to evolve in androdioecious than hermaphroditic populations, suggesting that evolution of dwarf males has preceded that of females in pedunculates. Both dwarf males and females are associated with a higher proportion of solitary individuals in the population, corroborating the hypothesis that limited mating opportunities have favoured evolution of these diverse sexual systems, which have puzzled biologists since Darwin.
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Mrosovsky, N., and Jane Provancha. "Sex ratio of loggerhead sea turtles hatching on a Florida beach." Canadian Journal of Zoology 67, no. 10 (October 1, 1989): 2533–39. http://dx.doi.org/10.1139/z89-358.
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Hatchling loggerhead sea turtles (Caretta caretta) were collected over the summer nesting season from a major rookery at Cape Canaveral, Florida, in 1986. Sex was assessed using histological criteria. From data on the distribution of nests over the season, we estimated that in 1986, > 93% of the hatchlings produced on this beach were females. This huge bias toward females is consistent with sand temperatures at the depth of turtle nests; for most of the season these temperatures were above the pivotal level for loggerhead turtles. The results suggest that in the future, turtles in this area will encounter difficulty in overcoming the feminizing effect of global warming and that biologists should pay more attention to the beaches at the northern end of the loggerhead's nesting range.
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Bleich, Vernon C., Jericho C. Whiting, John G. Kie, and R. Terry Bowyer. "Roads, routes and rams: does sexual segregation contribute to anthropogenic risk in a desert-dwelling ungulate?" Wildlife Research 43, no. 5 (2016): 380. http://dx.doi.org/10.1071/wr15231.
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Context Little is known about the consequences of sexual segregation (differential use of resources by the sexes outside of the mating season) for the conservation of large mammals. Roadways (i.e. the strip of land over which a road or route passes) are ubiquitous around the world, and are a major cause of wildlife mortality, as well as habitat loss and fragmentation. Many populations of bighorn sheep (Ovis canadensis) occur at low densities and in a metapopulation structure. Roadways could affect movements of males and females differentially, an outcome that has not been considered previously. Aims We investigated the propensity of the sexes to cross a paved two-lane road and a single-lane, maintained dirt route and predicted that adult males, because of their life-history characteristics, would cross those roadways more often than females. Methods We investigated movements of male and female bighorn sheep from 1986 to 1990. We used a fixed-wing aircraft with an H-antenna on each wing strut to locate individuals each week from October 1986 to December 1990. We estimated the degree of overlap among 50% core areas of use by males and females with the utilisation distribution overlap index (UDOI). Key results We relocated male and female bighorn sheep on 948 occasions during sexual aggregation and on 1951 occasions during sexual segregation. More males than females were likely to cross both types of roadways during segregation, and the dirt route during aggregation. Propensity of males and females to cross roadways was strongly influenced by time of year (i.e. whether the period of sexual aggregation or sexual segregation). The lowest overlap in 50% core areas was between females and males during periods of segregation (UDOI = 0.1447). Conclusions More males than females crossed Kelbaker Road and the unnamed dirt route during segregation, as well as the unnamed route during aggregation. Both of those features could affect males more than females, and could result in reductions in the use of habitat or increased mortality of bighorn sheep from vehicle collisions as a result of spatial segregation of the sexes. Implications During environmental review, biologists should consider sexual segregation when assessing potential anthropogenic effects on movements of bighorn sheep. Biologists also should consider sexual segregation and how roadways, even lightly traveled routes, affect movements of male and female ungulates differently before manipulating habitat, translocating animals, or constructing or modifying roadways.
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Laturney, Meghan, and Amanda J. Moehring. "The Genetic Basis of Female Mate Preference and Species Isolation in Drosophila." International Journal of Evolutionary Biology 2012 (August 23, 2012): 1–13. http://dx.doi.org/10.1155/2012/328392.
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The processes that underlie mate choice have long fascinated biologists. With the advent of increasingly refined genetic tools, we are now beginning to understand the genetic basis of how males and females discriminate among potential mates. One aspect of mate discrimination of particular interest is that which isolates one species from another. As behavioral isolation is thought to be the first step in speciation, and females are choosy more often than males in this regard, identifying the genetic variants that influence interspecies female mate choice can enhance our understanding of the process of speciation. Here, we review the literature on female mate choice in the most widely used model system for studies of species isolation Drosophila. Although females appear to use the same traits for both within- and between-species female mate choice, there seems to be a different genetic basis underlying these choices. Interestingly, most genomic regions that cause females to reject heterospecific males fall within areas of low recombination. Likely, candidate genes are those that act within the auditory or olfactory system, or within areas of the brain that process these systems.
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Luo, Laigao, Yilian Wu, Zhuyuan Zhang, and Xuefeng Xu. "Sexual size dimorphism and female reproduction in the white-striped grass lizard Takydromus wolteri." Current Zoology 58, no. 2 (April 1, 2012): 236–43. http://dx.doi.org/10.1093/czoolo/58.2.236.
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Abstract Sexual size dimorphism (SSD) has long attracted the attention of biologists, and life-history variation is thought to play an important role in the evolution of SSD. Here we quantified SSD and female reproductive traits to identify potential associations between SSD and female reproduction in the white-striped grass lizard Takydromus wolteri. In a population from Chuzhou, China, the largest male and female were 53.0 mm and 57.5 mm in snout-vent length (SVL), respectively. Females were larger in SVL and abdomen length, whereas males were larger in head size and tail length. Females produced up to five clutches of eggs during the breeding season, with large females producing more clutches and more eggs per clutch than small ones. As a result, large females had a higher annual fecundity and reproductive output. Egg size was positively correlated with maternal SVL in the first clutch, but not in subsequent clutches. These results suggest that T. wolteri is a species with female-biased SSD, and that fecundity selection, in which large females have higher fecundity due to their higher capacity for laying eggs, is likely correlated with the evolution of SSD in this species [Current Zoology 58 (2): 236–243, 2012].
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Gavin, Thomas A., and Eric K. Bollinger. "Multiple Paternity in a Territorial Passerine: The Bobolink." Auk 102, no. 3 (July 1, 1985): 550–55. http://dx.doi.org/10.1093/auk/102.3.550.
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Abstract Electrophoretic and behavioral evidence corroborate the conclusion that Bobolink (Dolichonyx oryzivorus) females occasionally copulate with more than one male, which results in the insemination of a single clutch of eggs by those males. In 2 of 12 families from which blood samples were obtained from the mother, the putative father, and the nestlings, at least 2 males were responsible for fertilization of the clutch. We believe this is only the second bird species in which multiple paternity has been documented conclusively in the wild. Our speculation that it may not be uncommon leads to a caution for evolutionary biologists who use apparent reproductive success in birds to address questions about fitness.
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Schuler, Krysten L., Bridget B. Baker, Karl A. Mayer, Carolina Perez-Heydrich, Paula M. Holahan, Nancy J. Thomas, and C. Leann White. "Refining Aging Criteria for Northern Sea Otters in Washington State." Journal of Fish and Wildlife Management 9, no. 1 (March 21, 2018): 208–21. http://dx.doi.org/10.3996/052017-jfwm-040.
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Abstract Measurement of skull ossification patterns is a standard method for aging various mammalian species and has been used to age sea otters Enhydra lutris from Russia, California, and Alaska. Cementum annuli counts have also been verified as an accurate aging method for sea otters in Alaska. In this study, we compared cementum annuli count results and skull ossification patterns as methods for aging the northern sea otter, E. l. kenyoni, in Washington State. We found significant agreement between the two methods, suggesting that either method could be used to age sea otters in Washington. We found that ossification of the squamosal–jugal suture at the ventral glenoid fossa can be used to differentiate male subadults from adults. To assist field biologists or others without access to cementum annuli or skull ossification analysis techniques, we analyzed a suite of morphologic, physiologic, and developmental characteristics to assess whether a set of these more easily accessible parameters could also predict age class. We identified tooth condition score, evidence of reproductive activity in females, and tooth eruption pattern as the most useful criteria for classifying sea otters in Washington. We created a simple decision tree based on characteristics accessible in the field or at necropsy, which can be used to reliably predict age class of Washington sea otters as determined by cementum annuli. These techniques offer field biologists and marine mammal stranding networks a replicable, cost-conscious methodology to gather useful biological information from sea otters.
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Cox, Robert M., Michele M. Barrett, and Henry B. John-Alder. "Effects of food restriction on growth, energy allocation, and sexual size dimorphism in Yarrow’s Spiny Lizard, Sceloporus jarrovii." Canadian Journal of Zoology 86, no. 4 (April 2008): 268–76. http://dx.doi.org/10.1139/z08-002.
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Evolutionary biologists often view sexual size dimorphism (SSD) as a fixed genetic consequence of sexually antagonistic selection, but the actual magnitude of SSD may often be strongly dependent upon proximate environmental factors. Sexual differences in growth rate lead to male-biased SSD in wild populations of Yarrow’s Spiny Lizard ( Sceloporus jarrovii Cope, 1875), yet both sexes grow at similar rates under controlled laboratory conditions. We hypothesized that male-biased SSD in S. jarrovii reflects an obligatory sexual difference in energy allocation to growth versus competing functions, but that an ad libitum diet provides an energy surplus which overwhelms this sex-specific energetic trade-off. To test this hypothesis, we reared juveniles under high (3 crickets/d) and low (1 cricket/d) food availabilities. Food restriction dramatically reduced growth in both sexes but did not differentially affect growth of females relative to males. Food consumption did not differ between sexes, but males grew slightly faster than females at both levels of food availability, indicating a greater fractional allocation of available energy to growth. By contrast, females had larger fat bodies than did males, particularly under food restriction. This sexual difference in energy allocation to storage could explain the slightly higher growth rate of males relative to females.
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Grant, T. R., and P. D. Temple–Smith. "Field biology of the platypus ( Ornithorhynchus anatinus ): historical and current perspectives." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 353, no. 1372 (July 29, 1998): 1081–91. http://dx.doi.org/10.1098/rstb.1998.0267.
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The field biology of the platypus, Ornithorhynchus anatinus , was first studied by a number of expatriate biologists who visited the Australian colonies to collect specimens in the 1800s. Their work was followed in the early to mid–1900s by a group of resident natural historians and later by an increasing number of academic biologists. All of these workers contributed significantly to the current understanding of the field biology of this unique Australian species. The platypus occupies much the same general distribution as it did prior to European occupation of Australia, except for its loss from the state of South Australia. However, local changes and fragmentation of distribution due to human modification of its habitat are documented. The species currently inhabits eastern Australia from around Cooktown in the north to Tasmania in the south. Although not found in the west–flowing rivers of northern Queensland, it inhabits the upper reaches of rivers flowing to the west and north of the dividing ranges in the south of the state and in New South Wales and Victoria. Its current and historical abundance, however, is less well known and it has probably declined in numbers, although still being considered as common over most of its current range. The species was extensively hunted for its fur until around this turn of this century. The platypus is mostly nocturnal in its foraging activities, being predominantly an opportunistic carnivore of benthic invertebrates. The species is homeothermic, maintaining its low body temperature (32°C), even while foraging for hours in water below 5°C. Its major habitat requirements include both riverine and riparian features which maintain a supply of benthic prey species and consolidated banks into which resting and nesting burrows can be excavated. The species exhibits a single breeding season, with mating occurring in late winter or spring and young first emerging into the water after 3—4 months of nurture by the lactating females in the nesting burrows. Natural history observations, mark and recapture studies and preliminary investigations of population genetics indicate the possibility of resident and transient members of populations and suggest a polygynous mating system. Recent field studies have largely confirmed and extended the work of the early biologists and natural historians.
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Zhang, Lixia, Yongsun Sheng, Xiangyu Yuan, Fei Yu, Xueting Zhong, and Xiaohong Chen. "Sexual dimorphism in Scutiger boulengeri, an endemic toad from the Tibetan Plateau." Animal Biology 70, no. 4 (September 15, 2020): 445–57. http://dx.doi.org/10.1163/15707563-bja10041.
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Abstract The evolution of sexual dimorphism has long fascinated evolutionary biologists and theory suggests that variation in sexual dimorphism is a consequence of selective forces acting differently on morphological traits in males versus females. Here, we analyzed sexual differences in size and shape of the Boulenger’s lazy toad, Scutiger boulengeri, based on the intersex variation pattern of sixteen morphometric traits including body size. The results suggested that sexual dimorphism was apparent in body size and some body shapes (e.g., head length and width, internasal space, interorbital space, diameter of lower arm and tibia width) of this toad. The bigger body size in females may be relevant to fecundity selection, a larger head in males as well as a broader internasal and interorbital space may be subject to male-male competition in combination with ecological selection, and both robust forelimbs and hindlimbs in males may be related to mating and competitive behaviors. These results are discussed with respect to the above selection procedures and possible sex differences in life history traits.
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Wagner, Kay-Uwe, Corinne A. Boulanger, MaLinda D. Henry, Magdalene Sgagias, Lothar Hennighausen, and Gilbert H. Smith. "An adjunct mammary epithelial cell population in parous females: its role in functional adaptation and tissue renewal." Development 129, no. 6 (March 15, 2002): 1377–86. http://dx.doi.org/10.1242/dev.129.6.1377.
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Mammary gland biologists have long assumed that differentiated secretory epithelial cells undergo programmed cell death at the end of lactation and that the alveolar compartment is reconstituted from undifferentiated precursor cells in subsequent pregnancies. It is generally agreed that the remodeled gland in a parous animal resembles that of a mature virgin at the morphological level. However, several physiological differences have been noted in comparing the responses of mammary epithelia from nulliparous versus parous females to hormonal stimulation and carcinogenic agents. We present genetic evidence that an involuted mammary gland is fundamentally different from a virgin gland, despite its close morphological resemblance. This difference results from the formation of a new mammary epithelial cell population that originates from differentiating cells during pregnancy. In contrast to the majority of fully committed alveolar cells, this epithelial population does not undergo cell death during involution or remodeling after lactation. We show that these cells can function as alveolar progenitors in subsequent pregnancies and that they can play an important role in functional adaptation in genetically engineered mice, which exhibit a reversion of a lactation-deficient phenotype in multiparous animals. In transplantation studies, this parity-induced epithelial population shows the capacity for self-renewal and contributes significantly to the reconstitution of the resulting mammary outgrowth (i.e. ductal morphogenesis and lobulogenesis). We propose that this parity-induced population contributes importantly to the biological differences between the mammary glands of parous and nulliparous females.
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Cvetkovic, Dragana, Natasa Tomasevic, I. Aleksic, and Andjelka Crnobrnja-Isailovic. "Phenotypic selection in common toad (Bufo bufo)." Archives of Biological Sciences 59, no. 4 (2007): 327–33. http://dx.doi.org/10.2298/abs0704327c.
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One of the most important problems for evolutionary biologists is to investigate the patterns and strength of phenotypic selection acting on quantitative traits in natural populations. Measurement of selection is complicated by the presence of correlations between characters; selection on a particular trait produces not only a direct effect, but indirect effects as well. Despite the growing body of phenotypic selection studies in a variety of taxa, studies on amphibians are still sparse. The aim of this study was to estimate patterns and strength of selection acting on a set of correlated characters in a natural population of Bufo bufo from the vicinity of Belgrade, Serbia. Morphological traits (body length, fore- and hind leg length) were measured, while fitness was assayed as fecundity and gonad weight for females and males, respec?tively. The regression approach was used to estimate selection differentials and gradients. Selection patterns differed between the sexes - linear selection differentials showed significant total directional selection for body size in females, but not in males. In males, differentials were significant for both fore- and hind leg lengths. Sample size did not permit identification of significant nonlinear (quadratic) selection.
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Sacchi, Roberto, Stefano Scali, Marco Mangiacotti, and Davide Ruffo. "Colour variation of the Maltese wall lizards (Podarcis filfolensis) at population and individual levels in the Linosa island." Rendiconti Lincei. Scienze Fisiche e Naturali 32, no. 3 (July 8, 2021): 565–75. http://dx.doi.org/10.1007/s12210-021-01010-3.
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AbstractThe research on animal colouration has always been of great interest for biologists but since the last decades it has grown exponentially thanks to multidisciplinary approaches. Animals have found several ways to deal with the camouflage/communication trade-off in colouration, leading to the evolution of alternative patterns of variation of colourations at different levels including signal partitioning and spatial resolution of colouration. In this paper we analyse the variability of dorsal and ventral colouration in males and females of Maltese wall lizards in three populations on Linosa. We collected high-resolution digital images of dorsal, ventral and throat colouration from 61 lizards (32 males and 29 females). We showed that the colouration differs among sexes and body regions within the same individual. Colourations are also variable among individuals within population, as well as among different populations across the Island. Finally, we detected a lizard’s colouration shifts with increasing body size. Those result supports the hypothesis that colouration in this species evolved under the competing pressures of natural and sexual selection to promote signals that are visible to conspecifics while being less perceptible to avian predators. Graphic abstract
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Jan, Kousar, and Imtiaz Ahmed. "Comparative study of length-weight relationships and biological indices of Himalayan snow trout, Schizothorax labiatus, inhabiting two lotic water bodies in the Kashmir Valley." Fisheries & Aquatic Life 29, no. 3 (September 1, 2021): 176–84. http://dx.doi.org/10.2478/aopf-2021-0019.
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Abstract The length-weight relationship (LWR) plays an important role in fishery management as it can be used to estimate the average weight of a specific length group. The results of the current study revealed that the mean values of regression coefficient b for both sexes of Schizothorax labiatus (McClelland) in the Jhelum River indicated positive allometric growth, while in the Sindh River, the b value for males indicated positive allometric growth and for females negative allometric growth. The value of coefficient of determination r2 for both sexes of S. labiatus was equal to or greater than 0.90 in both water bodies, except for females in the Sindh River. Higher significant (P < 0.05) average values of Fulton’s condition factor (K) and the hepatosomatic index (HSI) for both sexes of S. labiatus were noted in the Jhelum River than in the Sindh River. In contrast, higher significant (P < 0.05) values of the gonadosomatic index (GSI) were recorded in the Sindh River. The data generated during the current study provide basic information for researchers and fish biologists for the conservation and sustainable management of this commercially important food fish species in the Kashmir Valley.
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Kawakami, Yasuko, Kazuo Yamazaki, and Kazunori Ohashi. "Intergenerational fluctuations in colour morph frequencies may maintain elytral polymorphisms in the ladybird beetle Cheilomenes sexmaculata (Coleoptera: Coccinellidae)." Biological Journal of the Linnean Society 128, no. 3 (August 30, 2019): 725–34. http://dx.doi.org/10.1093/biolinnean/blz031.
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Abstract Phenotypic polymorphisms are found in a wide array of taxa, and unravelling the mechanisms that maintain them is of great interest to evolutionary and ecological biologists. Temporal environmental heterogeneity may play a role in the maintenance of polymorphisms but is poorly understood. In the present study, we analysed trends in intergenerational elytral colour morph frequencies in relation to changes in fitness and life history traits (i.e. body size, mortality, fecundity, hatching rate and mate preference) in the ladybird beetle Cheilomenes sexmaculata (Coleoptera: Coccinellidae). A long-term field survey spanning nine years showed that the frequency of dark morphs increases over winter and then decreases in spring. Dark morphs may have an advantage in winter due to their higher tolerance of low temperatures compared with light morphs. Light-morph females were heavier in winter than dark-morph females. They also mated more frequently and had higher hatching rates, potentially causing an increase in light morphs in spring. These results suggest that fluctuations in morph frequencies resulting from the conflicting directions of selection pressures between overwintering and spring generations may help to maintain genetic polymorphism.
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Parvizi, P., H. Taherkhani, and P. D. Ready. "Phlebotomus caucasicus and Phlebotomus mongolensis (Diptera: Psychodidae): indistinguishable by the mitochondrial cytochrome b gene in Iran." Bulletin of Entomological Research 100, no. 4 (November 26, 2009): 415–20. http://dx.doi.org/10.1017/s0007485309990423.
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AbstractDiagnostic molecular markers for the females of Phlebotomus (Paraphlebotomus) caucasicus and P. mongolensis were sought by characterizing from individual Iranian specimens a gene fragment, namely mitochondrial cytochrome b, that had previously proven useful for the taxonomy of phlebotomine sandflies. Males of both species were used as reference material because their external genitalia provide the only diagnostic morphological characters. A phylogenetic analysis of the new sequences, and those previously reported for P. grimmi, found no support for recognizing more than one species (P. caucasicus s.l.) in Iran. Most of the genetic variation was geographical. An absence of lineage sorting was demonstrated, and it is proposed that any search for species-specific molecular markers for these three taxonomic species should be continued by applied biologists only if there is better evidence for associating any one of them with phenotypes important for understanding the transmission of Leishmania species in foci of zoonotic cutaneous leishmaniasis.
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Nassef, Mohamed Zakaria, Daniela Melnik, Sascha Kopp, Jayashree Sahana, Manfred Infanger, Ronald Lützenberg, Borna Relja, Markus Wehland, Daniela Grimm, and Marcus Krüger. "Breast Cancer Cells in Microgravity: New Aspects for Cancer Research." International Journal of Molecular Sciences 21, no. 19 (October 5, 2020): 7345. http://dx.doi.org/10.3390/ijms21197345.
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Breast cancer is the leading cause of cancer death in females. The incidence has risen dramatically during recent decades. Dismissed as an “unsolved problem of the last century”, breast cancer still represents a health burden with no effective solution identified so far. Microgravity (µg) research might be an unusual method to combat the disease, but cancer biologists decided to harness the power of µg as an exceptional method to increase efficacy and precision of future breast cancer therapies. Numerous studies have indicated that µg has a great impact on cancer cells; by influencing proliferation, survival, and migration, it shifts breast cancer cells toward a less aggressive phenotype. In addition, through the de novo generation of tumor spheroids, µg research provides a reliable in vitro 3D tumor model for preclinical cancer drug development and to study various processes of cancer progression. In summary, µg has become an important tool in understanding and influencing breast cancer biology.
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Hanson, Christine L., and Hasmin S. Miller. "LEHs in Medieval Scandinavia: Preliminary Analysis." Dental Anthropology Journal 11, no. 3 (September 7, 2018): 9–12. http://dx.doi.org/10.26575/daj.v11i3.210.
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The development of enamel defects is a topic of considerable interest among skeletal biologists. Linear enamel hypoplasias (LEHs) are commonly studied, as they are generally thought to present stress-induced growth disruptions. The present research uses the frequency of LEH in spatially dispersed but chronologically compact samples to document regional differences in growth stress. Analysis of 1,068 teeth representing the permanent dentition of 921 individuals from six medieval sites in Denmark, Norway, and Greenland showed that the highest frequency of LEH occurred in the mandibular canine (29.13%) followed by the maxillary central incisor (27.51%). Comparison of these results with developmental charts, showing that maxillary incisor and mandibular canine crowns are completely formed between 4 and 7 years of age, indicated that early childhood was likely a stressful time for medieval Scandinavians. Overall, LEHs were more common in maxillary teeth than in mandibular teeth. Although statistically significant differences in LEH frequencies were not found between males and females, locations did differ significantly.
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LI, CONG, JOHN S. LEE, JENNIFER L. GROEBNER, HUENG-CHUL KIM, TERRY A. KLEIN, MONICA L. O’GUINN, and RICHARD C. WILKERSON. "A newly recognized species in the Anopheles Hyrcanus Group and molecular identification of related species from the Republic of South Korea (Diptera: Culicidae)." Zootaxa 939, no. 1 (April 15, 2005): 1. http://dx.doi.org/10.11646/zootaxa.939.1.1.
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We report here a previously unrecognized mosquito species from the Republic of South Korea that is closely related to Anopheles (Anopheles) sinensis. We also present an rDNA ITS2-based method for identification of this and the other morphologically similar Anopheles from the country. The PCR assay is a multiplex of seven primers in a single reaction that unambiguously identifies all included species. The other species include An. sinensis, An. lesteri, An. pullus, and a previously reported unknown Anopheles. Based on the ITS2 sequence, the two unnamed species have genetic distances from An. sinensis of 9.1% (unknown 1) and 10.7% (unknown 2), and are 10.6% different from each other. Adult females of An. sinensis and unknown 2 are morphologically indistinguishable, while unknown 1, An. lesteri and An. pullus can usually be separated from each other and from An. sinensis using available keys and descriptions. This PCR identification tool offers vector biologists and malaria epidemiologists a means to identify the potential vectors of malaria parasites in South Korea.
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Brassey, Charlotte A., Julia Behnsen, and James D. Gardiner. "Postcopulatory sexual selection and the evolution of shape complexity in the carnivoran baculum." Proceedings of the Royal Society B: Biological Sciences 287, no. 1936 (October 14, 2020): 20201883. http://dx.doi.org/10.1098/rspb.2020.1883.
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The baculum is an enigmatic bone within the mammalian glans penis, and the driving forces behind its often bizarre shape have captivated evolutionary biologists for over a century. Hypotheses for the function of the baculum include aiding in intromission, stimulating females and assisting with prolonged mating. Previous attempts to test these hypotheses have focused on the gross size of the baculum and have failed to reach a consensus. We conducted three-dimensional imaging and apply a new method to quantify three-dimensional shape complexity in the carnivoran baculum. We show that socially monogamous species are evolving towards complex-shaped bacula, whereas group-living species are evolving towards simple bacula. Overall three-dimensional baculum shape complexity is not related to relative testes mass, but tip complexity is higher in induced ovulators and species engaging in prolonged copulation. Our study provides evidence of postcopulatory sexual selection pressures driving three-dimensional shape complexity in the carnivore baculum.
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Simpson, Richard K., Michele A. Johnson, and Troy G. Murphy. "Migration and the evolution of sexual dichromatism: evolutionary loss of female coloration with migration among wood-warblers." Proceedings of the Royal Society B: Biological Sciences 282, no. 1809 (June 22, 2015): 20150375. http://dx.doi.org/10.1098/rspb.2015.0375.
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The mechanisms underlying evolutionary changes in sexual dimorphism have long been of interest to biologists. A striking gradient in sexual dichromatism exists among songbirds in North America, including the wood-warblers (Parulidae): males are generally more colourful than females at northern latitudes, while the sexes are similarly ornamented at lower latitudes. We use phylogenetically controlled comparative analysis to test three non-mutually exclusive hypotheses for the evolution of sexual dichromatism among wood-warblers. The first two hypotheses focus on the loss of female coloration with the evolution of migration, either owing to the costs imposed by visual predators during migration, or owing to the relaxation of selection for female social signalling at higher latitudes. The third hypothesis focuses on whether sexual dichromatism evolved owing to changes in male ornamentation as the strength of sexual selection increases with breeding latitude. To test these hypotheses, we compared sexual dichromatism to three variables: the presence of migration, migration distance, and breeding latitude. We found that the presence of migration and migration distance were both positively correlated with sexual dichromatism, but models including breeding latitude alone were not strongly supported. Ancestral state reconstruction supports the hypothesis that the ancestral wood-warblers were monochromatic, with both colourful males and females. Combined, these results are consistent with the hypotheses that the evolution of migration is associated with the relaxation of selection for social signalling among females and that there are increased predatory costs along longer migratory routes for colourful females. These results suggest that loss of female ornamentation can be a driver of sexual dichromatism and that social or natural selection may be a stronger contributor to variation in dichromatism than sexual selection.
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Høymork, Amund, and Eigil Reimers. "Antler development in reindeer in relation to age and sex." Rangifer 22, no. 1 (June 1, 2002): 75. http://dx.doi.org/10.7557/2.22.1.692.
Full textAbstract:
Yearling male and adult female reindeer (Rangifer tarandus tarandus) are similar in size and shape. If sexual clues are hidden, it can be difficult to distinguish between them. Antlers can be a useful aid in classifying yearling males and adult females, depending on whether specific antler characteristics are identifiable for these two groups. We recorded antler characteristics in a domestic reindeer herd (Vågå) and found considerable overlap in antler height, width and circumference between the different age and sex groups. Total tines and number of tine split-offs are use¬ful for the field biologist when discriminating among adult females, yearling males and 2.5 year-old males. For example, when using the tine split-offs with the suggested classification, 79% of the observed adult females and 76% of the yearling males were classified correctly. The antler height, width and circumference provide other biological dif¬ferences between groups, but are not easy to use to identify free ranging reindeer. This is due to the great overlap in antler size between the groups and measuring difficulties in a field study situation. Male and female calves have very similar antlers, and only the antler width is possible for sex discrimination, giving 67% accuracy of discriminating between these two groups.
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Pearce, G. P., and H. G. Spencer. "Population genetic models of genomic imprinting." Genetics 130, no. 4 (April 1, 1992): 899–907. http://dx.doi.org/10.1093/genetics/130.4.899.
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Abstract The phenomenon of genomic imprinting has recently excited much interest among experimental biologists. The population genetic consequences of imprinting, however, have remained largely unexplored. Several population genetic models are presented and the following conclusions drawn: (i) systems with genomic imprinting need not behave similarly to otherwise identical systems without imprinting; (ii) nevertheless, many of the models investigated can be shown to be formally equivalent to models without imprinting; (iii) consequently, imprinting often cannot be discovered by following allele frequency changes or examining equilibrium values; (iv) the formal equivalences fail to preserve some well known properties. For example, for populations incorporating genomic imprinting, parameter values exist that cause these populations to behave like populations without imprinting, but with heterozygote advantage, even though no such advantage is present in these imprinting populations. We call this last phenomenon "pseudoheterosis." The imprinting systems that fail to be formally equivalent to nonimprinting systems are those in which males and females are not equivalent, i.e., two-sex viability systems and sex-chromosome inactivation.
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Cvetkovic, Dragana, and V. Jovanovic. "Altitudinal variation of the sex ratio and segregation by gender in the dioecious plant Mercurialis perennis L. (Euphorbiaceae) in Serbia." Archives of Biological Sciences 59, no. 3 (2007): 193–98. http://dx.doi.org/10.2298/abs0703193c.
Full textAbstract:
The sex ratio is one of the most intriguing problems for evolutionary biologists. Spatio-temporal variation of male frequency in sexually dimorphic plant species, spatial segregation, and differential investment of the two sex functions have attracted much research interest. In this study, we examined altitudinal variation of the sex ratio and segregation by gender in Mercurialis perennis (dog?s mercury), a dioecious anemophilous species with wide distribution. The eight studied populations from Serbia represented an altitudinal range of 196 to 1480 m. Sex ratio was significantly biased in seven of the eight populations, with males outnumbering females 3.91:1 in the lowest-altitude population. Our results support the notion of spatial segregation of sexes along on altitudinal gradient: the frequency of males decreased with altitude, from 79.6% to 41.0%. The sex ratio was not significantly correlated with population density. We also examined intersexual differences of plant height in two populations from the extremes of the studied altitudinal range. Males were the larger sex in both populations, though the difference was not significant in the high-altitude population. .
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Flanagan, K. M., and J. Einarson. "Gender, Math Confidence, and Grit: Relationships with Quantitative Skills and Performance in an Undergraduate Biology Course." CBE—Life Sciences Education 16, no. 3 (September 2017): ar47. http://dx.doi.org/10.1187/cbe.16-08-0253.
Full textAbstract:
In a world filled with big data, mathematical models, and statistics, the development of strong quantitative skills is becoming increasingly critical for modern biologists. Teachers in this field must understand how students acquire quantitative skills and explore barriers experienced by students when developing these skills. In this study, we examine the interrelationships among gender, grit, and math confidence for student performance on a pre–post quantitative skills assessment and overall performance in an undergraduate biology course. Here, we show that females significantly underperformed relative to males on a quantitative skills assessment at the start of term. However, females showed significantly higher gains over the semester, such that the gender gap in performance was nearly eliminated by the end of the semester. Math confidence plays an important role in the performance on both the pre and post quantitative skills assessments and overall performance in the course. The effect of grit on student performance, however, is mediated by a student’s math confidence; as math confidence increases, the positive effect of grit decreases. Consequently, the positive impact of a student’s grittiness is observed most strongly for those students with low math confidence. We also found grit to be positively associated with the midterm score and the final grade in the course. Given the relationships established in this study among gender, grit, and math confidence, we provide “instructor actions” from the literature that can be applied in the classroom to promote the development of quantitative skills in light of our findings.
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Barrett, Spencer C. H. "Understanding plant reproductive diversity." Philosophical Transactions of the Royal Society B: Biological Sciences 365, no. 1537 (January 12, 2010): 99–109. http://dx.doi.org/10.1098/rstb.2009.0199.
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Flowering plants display spectacular floral diversity and a bewildering array of reproductive adaptations that promote mating, particularly outbreeding. A striking feature of this diversity is that related species often differ in pollination and mating systems, and intraspecific variation in sexual traits is not unusual, especially among herbaceous plants. This variation provides opportunities for evolutionary biologists to link micro-evolutionary processes to the macro-evolutionary patterns that are evident within lineages. Here, I provide some personal reflections on recent progress in our understanding of the ecology and evolution of plant reproductive diversity. I begin with a brief historical sketch of the major developments in this field and then focus on three of the most significant evolutionary transitions in the reproductive biology of flowering plants: the pathway from outcrossing to predominant self-fertilization, the origin of separate sexes (females and males) from hermaphroditism and the shift from animal pollination to wind pollination. For each evolutionary transition, I consider what we have discovered and some of the problems that still remain unsolved. I conclude by discussing how new approaches might influence future research in plant reproductive biology.
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Stoeckel, James, Brian Helms, Mathew Catalano, Jonathan M. Miller, Kesley Gibson, and Paul M. Stewart. "Field and model-based evaluation of a low-cost sampling protocol for a coordinated, crayfish life-history sampling effort." Freshwater Crayfish 21, no. 1 (December 31, 2015): 131–41. http://dx.doi.org/10.5869/fc.2015.v21-1.131.
Full textAbstract:
Abstract Life-history studies have been published for only a small proportion of crayfish species native to the southeastern United States. The Southeastern Crayfish Biologist Working Group was formed to help meet this deficit by coordinating life-history research efforts. We used a combination of field sampling and computer modeling to evaluate a basic core sampling protocol and assess sample size issues. We focused on a locally abundant species, Procambarus versutus, and followed the protocol for 5 months at two sites in Alabama. Results showed a monthly sample size of 10 juvenile males plus 10 adult males could be met consistently and provided a = 85% probability of detecting seasonal shifts in proportion of Form I males under a range of scenarios. Weaknesses of the effort included inconsistent determination of sex in juveniles and form of adult males among sampling crews. More importantly, female life-history information was rarely obtainable due to an inability to collect sufficient numbers of glaired or berried adults. We suggest several priorities to address before implementation of coordinated, large-scale sampling efforts. These include development of sampling techniques to increase captures of glaired and berried females, and assessment of non-lethal gamete extraction techniques to track reproductive state of males and females.
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CADENA-CASTAÑEDA, OSCAR J., SOFÍA MEDELLÍN-BECERRA, and JORGE MOLINA. "Studies on Neotropical Pseudophyllinae: A new, short-winged Platyphyllini genus (Orthoptera: Tettigoniidae) from a High Andean Forest in Colombia." Zootaxa 5190, no. 2 (September 28, 2022): 286–300. http://dx.doi.org/10.11646/zootaxa.5190.2.8.
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By combining different research disciplines, biologists can understand natural processes in a broader way. Here, we combine both taxonomic and bioacoustic methodologies to provide the first observations of the morphology, geographical distribution, and the acoustic behavior of the monotypic genus Andeophylloides n. gen. This katydid is the second short-winged genus of the tribe Platyphyllini, after Brachyplatyphylloides, both of which are found in the Colombian Andes. This new genus is unique, because it is the first to be collected in a High Andean Forest, in contrast to the other members of the tribe that have been found predominantly at lower elevations. The sound recordings showed males calling with an echeme duration in average of 5.9 ± 3.1 s, a peak frequency of 22.5 kHz, and peak activity starting at 19:00 and decreasing until 05:00. These calls occur mainly in the months of the first rainy season of the year (March to May). Andeophylloides zarauzensis n. sp., is the sixth species of platyphyllines which calling song is known. Additionally, we discuss the taxonomy, bioacoustics, and differentiate the species with Dasyscelidius atrifrons (Pleminiini). This is required as the females are superficially similar and both species share the same geographical distribution.
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Katsumura, Takafumi, Shoji Oda, Shigeki Nakagome, Tsunehiko Hanihara, Hiroshi Kataoka, Hiroshi Mitani, Shoji Kawamura, and Hiroki Oota. "Natural allelic variations of xenobiotic-metabolizing enzymes affect sexual dimorphism in Oryzias latipes." Proceedings of the Royal Society B: Biological Sciences 281, no. 1797 (December 22, 2014): 20142259. http://dx.doi.org/10.1098/rspb.2014.2259.
Full textAbstract:
Sexual dimorphisms, which are phenotypic differences between males and females, are driven by sexual selection. Interestingly, sexually selected traits show geographical variations within species despite strong directional selective pressures. This paradox has eluded many evolutionary biologists for some time, and several models have been proposed (e.g. ‘indicator model’ and ‘trade-off model’). However, disentangling which of these theories explains empirical patterns remains difficult, because genetic polymorphisms that cause variation in sexual differences are still unknown. In this study, we show that polymorphisms in cytochrome P450 ( CYP ) 1B1 , which encodes a xenobiotic-metabolizing enzyme, are associated with geographical differences in sexual dimorphism in the anal fin morphology of medaka fish ( Oryzias latipes ). Biochemical assays and genetic cross experiments show that high- and low-activity CYP1B1 alleles enhanced and declined sex differences in anal fin shapes, respectively. Behavioural and phylogenetic analyses suggest maintenance of the high-activity allele by sexual selection, whereas the low-activity allele possibly has experienced positive selection due to by-product effects of CYP1B1 in inferred ancestral populations. The present data can elucidate evolutionary mechanisms behind genetic variations in sexual dimorphism and indicate trade-off interactions between two distinct mechanisms acting on the two alleles with pleiotropic effects of xenobiotic-metabolizing enzymes.
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Girard, Madeline B., Damian O. Elias, and Michael M. Kasumovic. "Female preference for multi-modal courtship: multiple signals are important for male mating success in peacock spiders." Proceedings of the Royal Society B: Biological Sciences 282, no. 1820 (December 7, 2015): 20152222. http://dx.doi.org/10.1098/rspb.2015.2222.
Full textAbstract:
A long-standing goal for biologists has been to understand how female preferences operate in systems where males have evolved numerous sexually selected traits. Jumping spiders of the Maratus genus are exceptionally sexually dimorphic in appearance and signalling behaviour. Presumably, strong sexual selection by females has played an important role in the evolution of complex signals displayed by males of this group; however, this has not yet been demonstrated. In fact, despite apparent widespread examples of sexual selection in nature, empirical evidence is relatively sparse, especially for species employing multiple modalities for intersexual communication. In order to elucidate whether female preference can explain the evolution of multi-modal signalling traits, we ran a series of mating trials using Maratus volans . We used video recordings and laser vibrometry to characterize, quantify and examine which male courtship traits predict various metrics of mating success. We found evidence for strong sexual selection on males in this system, with success contingent upon a combination of visual and vibratory displays. Additionally, independently produced, yet correlated suites of multi-modal male signals are linked to other aspects of female peacock spider behaviour. Lastly, our data provide some support for both the redundant signal and multiple messages hypotheses for the evolution of multi-modal signalling.
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Meylan, Sandrine, Donald B. Miles, and Jean Clobert. "Hormonally mediated maternal effects, individual strategy and global change." Philosophical Transactions of the Royal Society B: Biological Sciences 367, no. 1596 (June 19, 2012): 1647–64. http://dx.doi.org/10.1098/rstb.2012.0020.
Full textAbstract:
A challenge to ecologists and evolutionary biologists is predicting organismal responses to the anticipated changes to global ecosystems through climate change. Most evidence suggests that short-term global change may involve increasing occurrences of extreme events, therefore the immediate response of individuals will be determined by physiological capacities and life-history adaptations to cope with extreme environmental conditions. Here, we consider the role of hormones and maternal effects in determining the persistence of species in altered environments. Hormones, specifically steroids, are critical for patterning the behaviour and morphology of parents and their offspring. Hence, steroids have a pervasive influence on multiple aspects of the offspring phenotype over its lifespan. Stress hormones, e.g. glucocorticoids, modulate and perturb phenotypes both early in development and later into adulthood. Females exposed to abiotic stressors during reproduction may alter the phenotypes by manipulation of hormones to the embryos. Thus, hormone-mediated maternal effects, which generate phenotypic plasticity, may be one avenue for coping with global change. Variation in exposure to hormones during development influences both the propensity to disperse, which alters metapopulation dynamics, and population dynamics, by affecting either recruitment to the population or subsequent life-history characteristics of the offspring. We suggest that hormones may be an informative index to the potential for populations to adapt to changing environments.
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Bukovsky, Antonin. "How Can Female Germline Stem Cells Contribute to the Physiological Neo-Oogenesis in Mammals and Why Menopause Occurs?" Microscopy and Microanalysis 17, no. 4 (July 16, 2010): 498–505. http://dx.doi.org/10.1017/s143192761000036x.
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AbstractAt the beginning of the last century, reproductive biologists have discussed whether in mammalian species the fetal oocytes persist or are replaced by neo-oogenesis during adulthood. Currently the prevailing view is that neo-oogenesis is functional in lower vertebrates but not in mammalian species. However, contrary to the evolutionary rules, this suggests that females of lower vertebrates have a better opportunity to provide healthy offspring compared to mammals with oocytes subjected to environmental threats for up to several decades. During the last 15 years, a new effort has been made to determine whether the oocyte pool in adult mammals is renewed as well. Most recently, Ji Wu and colleagues reported a production of offspring from female germline stem cells derived from neonatal and adult mouse ovaries. This indicates that both neonatal and adult mouse ovaries carry stem cells capable of producing functional oocytes. However, it is unclear whether neo-oogenesis from ovarian somatic stem cells is physiologically involved in follicular renewal and why menopause occurs. Here we review observations that indicate an involvement of immunoregulation in physiological neo-oogenesis and follicular renewal from ovarian stem cells during the prime reproductive period and propose why menopause occurs in spite of persisting ovarian stem cells.
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Pardo, Sebastián A., Andrew B. Cooper, John D. Reynolds, and Nicholas K. Dulvy. "Quantifying the known unknowns: estimating maximum intrinsic rate of population increase in the face of uncertainty." ICES Journal of Marine Science 75, no. 3 (January 5, 2018): 953–63. http://dx.doi.org/10.1093/icesjms/fsx220.
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Abstract Sensitivity to overfishing is often estimated using simple models that depend upon life history parameters, especially for species lacking detailed biological information. Yet, there has been little exploration of how uncertainty in life history parameters can influence demographic parameter estimates and therefore fisheries management options. We estimate the maximum intrinsic rate of population increase (rmax) for ten coastal carcharhiniform shark populations using an unstructured life history model that explicitly accounts for uncertainty in life history parameters. We evaluate how the two directly estimated parameters, age at maturity αmat and annual reproductive output b, most influenced rmax estimates. Uncertainty in age at maturity values was low, but resulted in moderate uncertainty in rmax estimates. The model was sensitive to uncertainty in annual reproductive output for the least fecund species with fewer than 5 female offspring per year, which is not unusual for large elasmobranchs, marine mammals, and seabirds. Managers and policy makers should be careful to restrict mortality on species with very low annual reproductive output <2 females per year. We recommend elasmobranch biologists to measure frequency distributions of litter sizes (rather than just a range) as well as improving estimates of natural mortality of data-poor elasmobranchs.
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Sakaluk, Scott, and W. Snedden. "Reproductive Biology of Cyphoderris strepitans: Copulatory Behavior and the Effect of Nuptual Feeding on Male Acoustic Activity." UW National Parks Service Research Station Annual Reports 12 (January 1, 1988): 125–31. http://dx.doi.org/10.13001/uwnpsrc.1988.2729.
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Cyphoderris strepitans is a relic species of the Haglidae, an ancient group abundant during the Triassic and thought to have given rise to the modern crickets and katydids. C. strepitans occurs in disjunct 'pockets' only in the mountains of Wyoming and Colorado and little is known of its role in the ecology of these sensitive areas. Several features of this animals behavior are of interest to the evolutionary biologist. The mating period of C. strepitans occupies a very narrow time window of approximately 1 month and under ideal weather conditions most mating can take place within a period of several weeks. Males becore acoustically active very early in the spring (early May) and are able to stridulate at temperatures below 0° C (Dodson et al 1983). In addition to providing females with a spermatophore at mating, males also provision females with a nuptial gift. This food gift takes the form of the male's fleshy matathorasic wings; females feed on the wing material, and resultant flow of heamolymph, while in copula. The mating behavior of C. strepitans has not previously been adequately described and thus it was the first objective of this study to quantify the specific behaviors of the copulatory sequence. The environmental conditions under which males stridulate are extremely harsh and calling likely represents a physiologically costly endeavor. In a previous study (Sakaluk et al 1987) we hypothesized that non-virgin males, having invested in both a spermatophore and nuptial provisioning and thus lost a significant energy reserve, should be limited in their ability to sustain calling in a demanding environmnent. This should result in reduced attraction of females and consequently reduced remating success. The results of our 1986 study were inconclusive although significant differences between groups were noted (Sakaluk et al 1987). Our second objective was to retest this hypothesis using more sensitive techniques.
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Aliaga- Rossel, Enzo, and Mariana Escobar-ww. "Translocation of trapped Bolivian river dolphins (Inia boliviensis)." IWC Journal of Cetacean Research and Management 21, no. 1 (September 10, 2020): 17–23. http://dx.doi.org/10.47536/jcrm.v21i1.96.
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The Bolivian river dolphin (Inia boliviensis), locally known as bufeo is an endemic species and categorized as Vulnerable in the Red Book of Vertebrates of Bolivia. Despite the fact that the Bolivian river dolphin is the only cetacean in land-locked Bolivia, knowledge about its conservation status and vulnerability to anthropogenic actions is extremely deficient. We report on the rescue and translocation of Bolivian river dolphins trapped in a shrinking segment of the Pailas River, Santa Cruz, Bolivia. Anthropogenic activities to alter the landscape and create agricultural land in the area include significant deforestation and irrigation channel construction and are likely to be a contributory factor causing the entrapment of these Bolivian River dolphins. The dolphins were trapped in shallow water in a 1 km section of river. Dry season water levels were rapidly falling and this section of river dried up completely. We collaborated with several institutions, authorities, and volunteers to translocate 26 Bolivian river dolphins, including calves, juveniles, and pregnant females. The dolphins were captured and transported using well-padded boats and vehicles and released into the Rio Grande. Each dolphin was accompanied by biologists who assured their welfare. No dolphins were injured or died during this process. If habitat degradation continue, it is likely that events in which river dolphins become trapped in South America may happen more frequently in the future.
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AUSTERLITZ, FRÉDÉRIC, and PETER E. SMOUSE. "Two-generation analysis of pollen flow across a landscape. III. Impact of adult population structure." Genetical Research 78, no. 3 (December 2001): 271–80. http://dx.doi.org/10.1017/s0016672301005341.
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The rate and distance of instantaneous pollen flow in a population are parameters of considerable current interest for plant population geneticists and conservation biologists. We have recently developed an estimator (Φft) of differentiation between the inferred pollen clouds that fertilize several females, sampled within a single population. We have shown that there is a simple relation between Φft and the average pollen dispersal distance (δ) for the case of a population with no geographic structure. Though forest trees usually show considerable pollen flow, assuming an absence of spatially distributed genetic structure is not always wise. Here, we develop analytical theory for the relation between Φft and δ, for the case where the probability of Identity by Descent (IBD) for two individuals decreases with the physical distance between them. This analytical theory allows us to provide an effective method for estimating pollen dispersal distance in a population with adult genetic structure. Using real examples, we show that estimation errors can be large if genetic structure is not taken into account, so it is wise to evaluate adult genetic structure simultaneously with estimation of Φft for the pollen clouds. We show that the results are only moderately affected by changes in the decay function, a result of some importance since no completely established theory is available for this function.
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Shu, Guocheng, Yuzhou Gong, Feng Xie, Nicholas C. Wu, and Cheng Li. "Effects of long-term preservation on amphibian body conditions: implications for historical morphological research." PeerJ 5 (September 15, 2017): e3805. http://dx.doi.org/10.7717/peerj.3805.
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Measurements of historical specimens are widely applied in studies of taxonomy, systematics, and ecology, but biologists often assume that the effects of preservative chemicals on the morphology of amphibian specimens are minimal in their analyses. We compared the body length and body mass of 182 samples of 13 live and preserved (up to 10 years) anuran species and found that the body length and body mass of preserved specimens significantly decreased by 6.1% and 24.8%, respectively, compared to those measurements of their live counterparts. The changes in body length and mass also exhibited highly significant variations between species. Similarly, there were significant differences in shrinkage of body length and body mass between sexes, where males showed greater shrinkage in body length and body mass compared to females. Preservation distorted the magnitude of the interspecific differences in body length observed in the fresh specimens. Overall, the reduction in body length or mass was greater in longer or heavier individuals. Due to the effects of preservation on amphibian morphology, we propose two parsimonious conversion equations to back-calculate the original body length and body mass of studied anurans for researchers working with historical data, since morphological data from preserved specimens may lead to incorrect biological interpretations when comparing to fresh specimens. Therefore, researchers should correct for errors due to preservation effects that may lead to the misinterpretation of results.
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Ghaffar, Abdul. "BIOLOGY AND ECOLOGICAL ADAPTATIONS OF BLACKBUCK (Antilope cervicapra): A REVIEW." Agrobiological Records 4 (2021): 23–31. http://dx.doi.org/10.47278/journal.abr/2020.023.
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Blackbuck is the existing members of genus Antilope which is most elegant and graceful among all Antelopes of Asia with distinct sexual dimorphism. Blackbuck show endemism in Pakistan, Nepal and India occupying mainly the semi-arid grassland areas. The name of species attributes towards the dark brownish to blackish coat color of male species. While female and the young ones are tawny or yellow. Chin undersides of legs and chest are white in both male and female individuals. Males have whorled horns with 79cm length with absence in females. The average body length of this animal is 100-150cm with the tail length of 10-17cm. The average body weight for male is 20-57kg and for female 19-33kg. Thin grassy forests, open and semi-desert areas are good habitat for it. Being diurnal and herbivorous, it acts as both grazers and browsers. It is the fastest animal with an average speed of 80km/h. It remains reproductively functional whole year. Reproductive disorders including dystocia and different infectious diseases due to ectoparasites, endoparasites, bacteria and viruses affect these species. Habitat loss, stress, illegal killing and genetic troubles cause the species to be ‘Extinct in the Wildlife’ in Pakistan so conservation strategies are underway for species protection. It is indispensable for zoologists and conservational biologists to observe the species for its conservation and confronting threats. Review article highlighted necessary information about species, which will clear the way for further research on species.
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Lapidge, Steven J., and Adam J. Munn. "Seasonal field metabolic rate and water influx of captive-bred reintroduced yellow-footed rock-wallabies (Petrogale xanthopus celeris)." Australian Journal of Zoology 59, no. 6 (2011): 400. http://dx.doi.org/10.1071/zo11049.
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Captive breeding and release is a tool used by conservation biologists to re-establish populations of endangered or locally extinct species. Reintroduced animals that have been bred in captivity must learn to meet the challenges posed by free living, and to adjust to local environmental conditions, food and water sources. How well reintroduced animals might meet these challenges is uncertain as few longitudinal studies have investigated the physiology of reintroduced animals or the implications of this for successful establishment of new populations. Here we have evaluated long-term, seasonal energy and water use by reintroduced yellow-footed rock-wallabies (Petrogale xanthopus celeris), an endangered medium-sized marsupial that inhabits rocky outcrops across Australia’s arid and semiarid rangelands. Captive-bred rock-wallabies were reintroduced to an area within the known boundaries of their former range, in south-western Queensland, Australia. Post-release water turnover rates (WTR) and field metabolic rates (FMR) were measured during their first wet summer and dry winter, by means of the doubly labelled water method. Total body water (73.1%), FMR (1650.0 kJ day–1), female fecundity (100%), and male and female body masses and survival were consistent between seasons, but rates of water turnover were significantly lower for all animals during the dry winter (174.3 mL day–1) than during the wet summer (615.0 mL day–1). There were no significant differences in WTR or FMR between males and lactating females (in either season).
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Zietsch, Brendan P., Hasse Walum, Paul Lichtenstein, Karin J. H. Verweij, and Ralf Kuja-Halkola. "No genetic contribution to variation in human offspring sex ratio: a total population study of 4.7 million births." Proceedings of the Royal Society B: Biological Sciences 287, no. 1921 (February 19, 2020): 20192849. http://dx.doi.org/10.1098/rspb.2019.2849.
Full textAbstract:
The ratio of males to females among an individual's offspring at birth (offspring sex ratio) has long been of great interest to evolutionary biologists. The human offspring sex ratio is around 1 : 1 and is understood primarily in terms of Fisher's principle (R. A. Fisher, The genetical theory of natural selection , 1930), which is based on the insight that in a population with an unequal sex ratio, each individual of the rarer sex will on average have greater reproductive value than each individual of the more common sex. Accordingly, individuals genetically predisposed to produce the rarer sex will tend to have greater fitness and thus genes predisposing to bearing that sex will increase in frequency until the population sex ratio approaches 1 : 1. An assumption of this perspective is that individuals' offspring sex ratio is heritable. However, the heritability in humans remains remarkably uncertain, with inconsistent findings and important power limitations of existing studies. To address this persistent uncertainty, we used data from the entire Swedish-born population born 1932 or later, including 3 543 243 individuals and their 4 753 269 children. To investigate whether offspring sex ratio is influenced by genetic variation, we tested the association between individuals' offspring's sex and their siblings' offspring's sex ( n pairs = 14 015 421). We estimated that the heritability for offspring sex ratio was zero, with an upper 95% confidence interval of 0.002, rendering Fisher's principle and several other existing hypotheses untenable as frameworks for understanding human offspring sex ratio.
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Tarr, Matthew D., and Peter J. Pekins. "Influences of winter supplemental feeding on the energy balance of white-tailed deer fawns in New Hampshire, U.S.A." Canadian Journal of Zoology 80, no. 1 (January 1, 2002): 6–15. http://dx.doi.org/10.1139/z01-200.
Full textAbstract:
The purpose of this study was to determine the influence of supplemental feeding on the energy balance of white-tailed deer (Odocoileus virginianus) in northern New Hampshire, U.S.A., during JanuaryMarch 1997. We measured the field metabolic rate (FMR) and energy balance of 10 (5 males and 5 females) supplementally fed wild fawns with doubly labeled water over 1921 days. We tested whether percent acid detergent fiber (ADF) and percent neutral detergent fiber in deer fecal samples predicted the proportion of supplemental feed (pelleted concentrate) in the diet of deer. The mean FMR of fawns was 758.4 kJ·kg0.75·d1 (range = 535.91032.8 kJ·kg0.75·d1), or 2 × their basal metabolic rate (BMR). The mean FMR of male fawns was >30% higher than that of female fawns. Percent body fat (12.1 ± 1.4% (mean ± SE)) and mass loss (3.0 ± 0.9%) varied among fawns, suggesting that an individual high FMR was not detrimental to energy balance and was related to availability of feed. We estimated that a high FMR (>2 × BMR) could be maintained only if fawns consumed about 1 kg of supplemental feed daily. Radiotelemetry data indicated that the number and juxtaposition of feeding sites in an area probably influenced home range and activity of deer. Percent ADF in feces provided the best prediction of percent grain in the diet (% grain = 0.048(% ADF)2 + 1.523(% ADF) + 96.467; r2 = 0.69) and was useful for identifying populations consuming supplemental pelleted concentrate. Biologists should expect that the influence of winter feeding on energy balance and survival will vary according to the interrelationships of deer density, food availability, and winter severity at feeding sites.
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Pearce, John M., and Sandra L. Talbot. "Demography, Genetics, and the Value of Mixed Messages." Condor 108, no. 2 (May 1, 2006): 474–79. http://dx.doi.org/10.1093/condor/108.2.474.
Full textAbstract:
Abstract Iverson et al. (2004) used estimates of the homing rate for molting adult Harlequin Ducks (Histrionicus histrionicus) in Alaska to draw inferences about population structure. Homing rates, defined as one minus the ratio of birds recaptured elsewhere to those recaptured at the original banding site, were high (0.95–1.00) for males and females. Iverson et al. (2004) concluded that these high rates of homing are indicative of demographic independence among molting groups separated by small distances (tens to hundreds of kilometers) and that conservation efforts should recognize this fine-scale population structure. We re-examined their use of the homing rate, because their assumption of equal detection probability across a wide sampling area could have led to an upward bias in their estimates of site fidelity. As a result, we are hesitant to agree with their conclusion of high adult homing to molting areas and that molt-site fidelity is evidence for demographic independence. Our hesitancy stems from the fact that little is known about juvenile and adult movements within and among years, breeding area origins, and the variation of demographic parameters (e.g., survival and productivity) among molting groups. Furthermore, population genetic data of these molting groups suggest gene flow at both nuclear and mitochondrial loci. Such mixed messages between demographic (i.e., banding) and genetic data are increasingly common in ornithological studies and offer unique opportunities to reassess predictions and make more robust inferences about population structure across broad temporal and spatial scales. Thus, we stress that it is this broader scale perspective, which combines both demography and genetics, that biologists should seek to quantify and conservation efforts should seek to recognize.
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Dembkowski, Daniel J., Daniel A. Isermann, and Ryan P. Koenigs. "Walleye Age Estimation Using Otoliths and Dorsal Spines: Preparation Techniques and Sampling Guidelines Based on Sex and Total Length." Journal of Fish and Wildlife Management 8, no. 2 (August 1, 2017): 474–86. http://dx.doi.org/10.3996/052017-jfwm-038.
Full textAbstract:
Abstract We used dorsal spines and otoliths from 735 Walleye Sander vitreus collected from 35 Wisconsin water bodies to evaluate whether 1) otolith and dorsal spine cross sections provided age estimates similar to simpler methods of preparation (e.g., whole otoliths and dorsal spines, cracked otoliths); and 2) between-reader precision and differences between spine and otolith ages varied in relation to total length (TL), sex, and growth rate. Ages estimated from structures prepared using simpler techniques were generally similar to ages estimated using thin sections of dorsal spines and otoliths, suggesting that, in some instances, much of the additional processing time and specialized equipment associated with thin sectioning could be avoided. Overall, between-reader precision was higher for sectioned otoliths (mean coefficient of variation [CV] = 3.28%; standard error [SE] = 0.33%) than for sectioned dorsal spines (mean CV = 9.20%; SE = 0.56%). When using sectioned otoliths for age assignment, between-reader precision did not vary between sexes or growth categories (i.e., fast, moderate, slow), but between-reader precision was higher for females than males when using sectioned dorsal spines. Dorsal spines were generally effective at replicating otolith ages for male Walleye <450 mm TL and female Walleye <600 mm TL, suggesting that dorsal spines can be used to estimate ages for male Walleye <450 mm TL and female Walleye <600 mm TL. If sex is unknown, we suggest dorsal spines be used to estimate ages for Walleye <450 mm TL, but that otoliths be used for fish >450 mm TL. Our results provide useful guidance on structure and preparation technique selection for Walleye age estimation, thereby allowing biologists to develop sampling guidelines that could be implemented using information that is always (TL) or often (sex) available at the time of fish collection.
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Prommer, Mátyás, and János Bagyura. "Review of the development of the Peregrine Falcon (Falco peregrinus) population in Hungary between 1997 and 2018." Ornis Hungarica 26, no. 2 (December 1, 2018): 2–11. http://dx.doi.org/10.1515/orhu-2018-0011.
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Abstract Peregrine Falcon (Falco peregrinus) populations recovered globally after a dramatic decline experienced between the 1950s and 1980s. The conservation challenge forced the raptor biologist community to co-operate internationally. As a part of the co-operation, four conferences were organised to identify the problem, coordinate conservation efforts including research and to monitor the recovery process of the species’ populations worldwide. The line of conferences started in Madison (WI, USA) in 1965 and was followed by two conferences in Sacramento (CA, USA) and Piotrowo/Poznań (Poland) in 1985 and in 2007, respectively. The latest conference was organised in 2017, in Budapest, where Peregrine experts discussed the latest research and monitoring results. The event provides a good occasion to review the development of the Peregrine population in Hungary. The species became extinct in Hungary as a breeding species in the mid-1960s due to the intensive use of pesticides (DDT) and it returned only in 1997, when the first successful breeding was recorded. In 2018, 72 active eyries were recorded. The Hungarian population is the edge of the Carpathian Peregrine population and the birds represent mostly the nominate subspecies (F. p. peregrinus), but individuals showing typical phenotype of the Mediterranean subspecies (F. p. brookei) were also observed. The northern race of F. p. calidus also occurs on migration and in winter. The Hungarian population is sedentary. Natal dispersal of females is biased to males, but in case of both sexes most ring recoveries of adult birds occurred within the Pannonian basin. The increasing Peregrine population expanding to the lowland may cause conservation conflict on medium term by competing with the endangered Saker Falcon (Falco cherrug) for the nest sites. The conservation status of the Peregrine Falcon in Hungary is good in general, but threats may emerge on local scale in some regions. No specific conservation measures are taken, research and monitoring focus on population changes and threats posed on and caused by Peregrines.
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Deau, Benedicte, Mathias Montveneur, Valérie Coiteux, Aline Renneville, Francoise Rigal-Huguet, Eric Delabesse, Michel Tulliez, et al. "Clinical Phenotype and Response to Imatinib of Chronic Myelogenous Leukemia Patients Harbouring Atypical BCR-ABL Transcripts. A Retrospective Analysis From the French Group of CML (Fi-LMC) and the French Group of Molecular Biologists for Hematological Malignancies (GBMHM)." Blood 116, no. 21 (November 19, 2010): 3378. http://dx.doi.org/10.1182/blood.v116.21.3378.3378.
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Abstract Abstract 3378 Chronic Myelogenous Leukemia (CML) originates in the Philadelphia chromosome, a reciprocal translocation creating the fusion oncogene BCR-ABL. In 1–2% of CML cases, breakpoints fall outside the M-BCR gene on chromosome 22, leading to the synthesis of a variety of atypical BCR-ABL transcripts [shortened: e1a2 (m-BCR), e6a2, e8a2, b2a3 (e13a3), b3a3 (e14a3), or elongated transcripts: e19a2 (m-BCR)] and to the synthesis of different molecular weight BCR-ABL proteins that might have different tyrosine kinase activities. Thus, clinical phenotypes and BCR-ABL inhibition by tyrosine kinase inhibitors might be different and lead to different prognostic features. We retrospectively analysed at the national level, the clinical characteristics and the responses to imatinib (IM) of 63 patients with CML harbouring atypical BCR-ABL transcripts: 22 e1a2 [Group 1 (G1)], 20 e19a2 [Group 2 (G2)], 5 e8a2 [Group 3 (G3)], 4 e6a2 [Group 4 (G4)], 5 b2a3 [Group 5 (G5)], and 3 b3a3 [Group 6 (G6)] BCR-ABL transcripts. The general characteristics of the patients and their best response to IM are depicted in Table 1: Table 1 Group 1(e1a2) Group 2 (e19a2) Group 3 (e8a2) Group 4 (e6a2) Group 5 (b2a3) Group 6 (b3a3) n 22 20 5 8 5 3 M/F 7/15 6/14 4/1 4/4 5/0 0/3 Median age (years) 70 69 43 57 62 47 CP/AccP/MBC 20/0/2 17/1/2 5/0/0 4/1/3 4/1/0 2/1/0 Sokal (L/H/I/Ukn)* 6/8/2/4 1/3/9/4 3/1/0/1 1/2/1/0 1/2/0/1 0/2/0/0 Leukocytes (G/l, median) 60.85 28.3 55 28.4 93 82.4 Hemoglobin (g/dl, median) 12 10.2 11.7 10.95 11.1 10.2 Platelets (G/l, median) 303 848 253 259 167 363 Monocytes (G/l median) 4.8 0.8 2.34 0.05 1.08 0.825 Additional Clonal Abnormalities at diag (% of patients) 20 28 0 29 25 0 IM duration (median, years) 1.55 1.38 1.58 0.8 1.13 1.42 Interval Diagnosis-IM (median, years) 1.31 1.48 1 1.17 0.87 1.66 Best response to IM* No response 20 0 0 0 0 0 CHR (%) 13 32 0 0 0 0 Minor CyR (%) 47 0 0 0 0 0 PCyR (%) 0 10 20 10 25 67 CCyR (%) 13 32 60 50 0 0 MMR (%) 7 26 20 40 75 33 Follow-up since diag (median, years) 3.24 1.57 1.6 3.82 1.5 1.68 (CP states for Chronic phase, AccP for accelerated phase, MBC for myeloid blast crisis, L for Low, I for intermediate, H for High, Ukn for Unknown, * For CP patients only) Surprisingly, e1a2 and e19a2 transcripts seem significantly more frequent in females than in males conversely to typical BCR-ABL transcripts (p=0.01) and occurring more often in the elderly (p=0.05). The majority of the patients presented with typical cytological CML features, however, a significant monocytosis was observed in e1a2 and e8a2 atypical transcripts (p=0.0002). The median time on IM and the interval between diagnosis and IM were not statistically different between the 6 groups. Overall, there was no significant difference in the (hematologic, cytogenetic, molecular) responses to IM, but e1a2 transcripts seem less sensitive to this agent. The overall survival since diagnosis or since IM initiation was not different between atypical transcripts (p=0.55 and p=0.73 respectively), however, the progression-free survival (PFS) since diagnosis with e1a2 transcripts was significantly worse than for all other atypical transcripts (p=0.02) as shown in Figure 1: The PFS since IM initiation was somewhat worse for e1a2 transcripts, but close to significance (p=0.09), but the follow-up is not very long yet. Fifteen patients among 63 had second generation TKIs (TKI2), 7 in group 1, 3 in group 2, 1 in groups 3, 4, 5, and 2 in group 6. Only one patient (b3a3 transcript) developed a MBC being on IM. Two patients developed a T315I BCR-ABL mutation (1 e1a2, and 1 e6a2). Two patients got allo-transplanted (1 e1a2 alive and well at last follow-up, 1 e19 a2 died from GVHD). In conclusion, atypical BCR-ABL transcripts induce a particular molecular and subsequent clinical phenotypes, particularly e1a2 transcripts showing in this study poor prognosis features. The response of atypical BCR-ABL transcripts to IM might vary from that what it is for classical M-BCR transcripts, but a longer follow-up is needed. Disclosures: No relevant conflicts of interest to declare.
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Monecke, Stefanie. "All things considered? Alternative reasons for hamster extinction." Zoologica Poloniae 58, no. 3-4 (December 1, 2013): 41–57. http://dx.doi.org/10.2478/zoop-2013-0004.
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Abstract In 2002 a pest biologist (LEIRS 2002) calculated the survival chances of the European hamster (Cricetus cricetus) according to data provided by participants of the meeting of the International Hamster Workgroup in Tongeren. His model was based predominantly on demographic data as birth rates and predicted that the European hamster will be extinct in Western Europe within the next 50 years. Since then, the mean number of litters females raise in a year has diminished from 2-3 to 1-2. It is thus to be feared that the remaining time is only half as long as predicted and extinction might occur around 2030. However, since then hamster protection measures have improved considerably and two major milestones have been reached: (1) we are able to breed captive hamsters in a sufficient number and (2) most released hamsters survive long enough to reproduce once. Thus, at the present state we can claim that the hamster won.t go extinct as long as such breeding and releasing programs are in place. However, we haven.t achieved a state yet at which it is clear that the hamster will survive with its own means when such programs are stopped. To work on this will be the task of the coming years. This review might be a starting point for that. It reflects on which other factors possibly impair the survival of European hamster populations besides some aspects of modern agriculture, thus it searches for parameters which are not yet considered in conservation programs. Historical data as well as observations and research data from other species are reviewed. Additionally, new insights from the subterranean life of European hamsters in outdoor terrariums are presented, which suggest that the soil as habitat might need more attention in conservation. However, this conjecture can provide only new ideas, which still have to be confirmed by research. The intention is to spark a lively discussion on such potential alternative reasons for the decline of European hamsters, whether some of them are worth being investigated and whether we overlooked something. There is not much time left.
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C., Rosell, and F. Llimona. "Human–wildlife interactions." Animal Biodiversity and Conservation 35, no. 2 (December 2012): 219–20. http://dx.doi.org/10.32800/abc.2012.35.0219.
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219Animal Biodiversity and Conservation 35.2 (2012)© 2012 Museu de Ciències Naturals de BarcelonaISSN: 1578–665XRosell, C. & Llimona, F., 2012. Human–wildlife interactions. Animal Biodiversity and Conservation, 35.2: 219–220. The nature of wildlife management throughout the world is changing. The increase in the world’s human population has been accompanied by a rapid expansion of agricultural and urban areas and infrastructures, especially road and railway networks. Worldwide, wildlife habitats are being transformed and fragmented by human activities, and the behavior of several species has changed as a result of human activities. Some species have adapted easily to urban or peri–urban habitats and take advantage of the new resources available. These data provide the context for why human–wildlife interactions are increasing. At the 30th International Union of Game Biologists Congress held in Barcelona in early September 2011, in addition to two plenary presentations, 52 authors from 12 different countries and three continents presented 15 papers in the Interactions of Humans and Wildlife Session, three of which are included in this volume. To some extent, all the papers reflected the inherent difficulty in solving the complex problems caused either by rapidly increasing species that begin to inhabit urban and agricultural areas in numbers not seen previously (e.g. coyo-tes, Canis latrans, inhabiting big cities; wild boar, Sus scrofa, across western Europe; wood pigeons, Columba palumbus, in France), or species whose populations are threatened by human activities (e.g., Eurasian Lynx, Lynx lynx, in the Czech Republic). Some papers addressed the contentious issue of predator control (e.g., gamebirds in Great Britain), while others presented data regarding how human activities influenced animal behavior (e.g., pink footed geese, Anser brachyrhynchus; and red deer, Cervus elaphus, in Germany). The papers presented at the congress show how human activities affect the distributions and dynamics of wildlife populations and also change the behavior of some species. Wildlife causes social and economic con-flicts by damaging agricultural and forest resources, bringing about traffic collisions, and creating problems for residents in urban areas; while many are increasingly distant from nature and may not accept the presence of wildlife others may actively encourage the presence of wild animals. The first paper in this volume, by Cahill et al. (2012), analyzes the management challenges of the increasing abundance of wild boar in the peri–urban area of Barcelona. This conflict has arisen in other large cities in Europe and elsewhere. The presence of the species causes problems for many residents, to such an extent that it is considered a pest in these areas. Wild boar habituation has not only been facilitated by population expansion, but also by the attitudes of some citizens who encourage their presence by direct feeding. This leads to wild boar behavior modification and also promotes an increase in the fertility rate of habituated females, which are significantly heavier than non–habituated females. Public attitudes regarding the species and harvesting methods (at present most specimens are removed by live capture and subsequently sacrificed) are highlighted as one of the key factors in the management of the conflict. The second paper provides an example of how the distribution of irrigated croplands influences wild boar roadkills in NW Spain (Colino–Rabanal et al., 2012). By modeling the spatial distribution of wild boar collisions with vehicles and using generalized additive models based on GIS, the authors show that the number of roadkills is higher in maize croplands than in forested areas. This factor is the main explanatory variable in the model. The paper provides an excellent example of how the synergies of diverse human elements in the landscape (maize croplands and roads in this case) affect the location and dimensions of these types of conflicts. The third and final paper, by Belotti et al. (2012), addresses the effects of tourism on Eurasian lynx movements and prey usage at Šumava National Park in the Czech Republic. The monitoring of 5 GPS–collared lynxes and analyses of data regarding habitat features suggests that human disturbance (proximity of roads and tourist trails) can modify the presence of lynxes during the day close to the site where they have hidden a prey item, such as an ungulate, that can provide them with food for several days. In such cases, adequate management of tourism development must involve a commitment to species conservation. The analyses and understanding of all these phenomena and the design of successful wildlife management strategies and techniques used to mitigate the conflicts require a good knowledge base that considers informa-tion both about wildlife and human attitudes. The papers presented stress the importance of spatial analyses of the interactions and their relationship with landscape features and the location of human activities. Species distribution and abundance are related to important habitat variables such as provision of shelter, food, comfor-table spaces, and an appropriate climate. Therefore, it is essential to analyze these data adequately to predict where conflicts are most likely to arise and to design successful mitigation strategies. The second key factor for adequate management of human–wildlife interactions is to monitor system change. An analysis of the variety of data on population dynamics, hunting, wildlife collisions, and wildlife presence in urban areas would provide a basis for adaptive management. In this respect, in the plenary session, Steve Redpath mentioned the importance of the wildlife biologist’s attitude when interpreting and drawing conclusions from recorded data and stressed the importance of conducting clear, relevant, and transparent science for participants involved in the management decision process, which often involves a high number of stakeholders. All of the papers addressing the problems associated with human wildlife interactions were characterized by a common theme. Regardless of the specific nature of the problem, the public was generally divided on how the problem should be addressed. A particularly sensitive theme was that of population control methods, especially when conflicts are located in peri–urban areas. Several presenters acknowledged that public participation was necessary if a solution was to be reached. Some suggested, as have other authors (Heydon et al., 2010), that a legislative framework may be needed to reconcile human and wildlife interests. However, each problem that was presented appeared to involve multiple stakeholders with different opinions. Solving these kinds of problems is not trivial. Social factors strongly influence perceptions of human–wildlife conflicts but the methods used to mitigate these conflicts often take into account technical aspects but not people’s attitudes. A new, more innovative and interdisciplinary approach to mitigation is needed to allow us 'to move from conflict towards coexistence' (Dickman, 2010). Other authors also mentioned the importance of planning interventions that optimize the participation of experts, policy makers, and affected communities and include the explicit, systematic, and participatory evaluation of the costs and benefits of alternative interventions (Treves et al., 2009). One technique that has been used to solve problems like these is termed Structured Decision Making (SDM). This technique was developed by the U.S. Geological Survey and the U.S. Fish and Wildlife Service. As described by Runge et al. (2009), the process is 'a formal application of common sense for situations too complex for the informal use of common sense', and provides a rational framework and techniques to aid in prescriptive decision making. Fundamentally, the process entails defining a problem, deciding upon the objectives, considering the alternative actions and the consequences for each, using the available science to develop a model (the plan), and then making the decision how to implement (Runge et al., 2009). Although complex, SDM uses a facilitator to guide stakeholders through the process to reach a mutually agreed–upon plan of action. It is clear that human–wildlife interactions are inherently complex because many stakeholders are usually involved. A rational approach that incorporates all interested parties would seem to be a productive way of solving these kinds of problems
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Pyda, S. V., N. N. Barna, and L. S. Barna. "ВІДОМИЙ УКРАЇНСЬКИЙ ВЧЕНИЙ-БІОЛОГ ТА ПЕДАГОГ (ДО 85-РІЧЧЯ ВІД ДНЯ НАРОДЖЕННЯ)." Scientific Issue Ternopil Volodymyr Hnatiuk National Pedagogical University. Series: Biology 80, no. 3-4 (December 1, 2020): 139–44. http://dx.doi.org/10.25128/2078-2357.20.3-4.17.
Full textAbstract:
The article covers the scientific, pedagogical and public activities of biologist, plant physiologist, candidate of biological sciences, associate professor and head of the Department of Botany (1988–2002), rector of the Ternopil State Pedagogical Institute (1982–1984) Ivan Mykolaiovych Butnytskyi. The scientist went from an assistant to the head of the Department of Botany, vice-rector for academic affairs (1979–2002), rector of the Ternopil State Pedagogical Institute (2002–2004).
In 1975 he successfully defended his dissertation on "Polarity and physiological-biochemical features of sexualization of some dioecious plants" for the degree of candidate of biological sciences in the specialty – plant physiology. By the decision of the Academic Council of Chernivtsi State University of December 29, 1975 Ivan Mykolaiovych Butnytskyi was awarded the degree of Candidate of Biological Sciences and by the decision of the High Attestation Commission of the USSR Council of Ministers of December 23, 1981 - the academic title of associate professor of botany. The direction of his research was to study the features of sexualization of tissues of female and male forms of dioecious plants; study of the activity of some oxidative enzymes in males and females of dioecious plants, the effect of photoperiodism on the growth of aboveground and underground organs in some dioecious plants, the effect of inoculation on the formation of root nitrogen-fixing nodules and increase alfalfa yield in Western Podillya; study of activation of bean-rhizobial symbiosis of alfalfa in the absence of the use of heterologous lectins, etc.
I. M. Butnytskyi actively develops methodological aspects of improving the preparation of courses "Plant Physiology", especially increasing the independent activity of students in the process of preparation for laboratory classes and educational practice in this course. I. M. Butnytskyi was a talented and responsible organizer of higher education, proved to be principled, hardworking, conscientious in the performance of official duties, persistent in achieving the goal, a teacher with deep theoretical knowledge, which he generously shared with students, teachers in postgraduate courses, in the lecture hall of the society «Knowledge», enjoyed leadership among teachers and students, conducted research, participated in the education of student youth and the implementation of measures for the organic combination of the institute with the work of secondary schools in the region and city.
I. M. Butnytskyi’s active public and scientific activity was noted by the state. He was awarded the Veteran of Labor Medal (1987), the Badge of Excellence in Public Education of the Ukrainian SSR (1982) and two Diplomas of the Ministry of Defense of the Ukrainian SSR (1958 and 1990). He was elected a deputy of the Ternopil City Council of People's Deputies. For many years he headed the Ternopil branch of the Ukrainian Society of Plant Physiologists.
He is the author of more than 130 scientific and scientific-methodical works, including two patents of Ukraine for inventions.
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Miller, Frank L., Samuel J. Barry, and Wendy A. Calvert. "The role of seasonal migration in the near-total loss of caribou on south-central Canadian Arctic Islands." Rangifer 27, no. 4 (April 1, 2007): 243. http://dx.doi.org/10.7557/2.27.4.349.
Full textAbstract:
Extended: In 1980 the caribou (Rangifer tarandus) on Prince of Wales, Russell, and Somerset islands represented a healthy geographic population of an Arctic-island caribou ecotype on the southern tier of Canadian Arctic Islands. Those caribou exhibited complex patterns of seasonal range occupancy, involving annual seasonal migrations between and among the three islands and Boothia Peninsula (Miller et al., 1982, 2005; Miller, 1990). A large segment of the population migrated annually from the islands to Boothia Peninsula in early winter, wintered there, and then returned to the islands in the following late winter and spring. There is no evidence for large-scale emigration of caribou anywhere in the study area (Gunn et al., 2006). Caribou on Boothia Peninsula occur as two distinct ecotypes that are genetically different from the Arctic-island ecotype that occurred on Prince of Wales, Russell, and Somerset islands (e.g., Zittlau, 2004). Both the Boothia Peninsula ecotype and the Mainland ecotype calve mostly on northern Boothia Peninsula, northwest and northeast sections respectively (Gunn et al., 2000). After summering on the peninsula, most individuals of both ecotypes migrate south of the Boothia Isthmus onto adjacent mainland areas (Gunn et al., 2000). As a result, there were about the same number of caribou wintering on Boothia Peninsula when migrant caribou from Prince of Wales, Russell, and Somerset islands wintered there, as in summer when the migrant Arctic-island caribou had returned to Prince of Wales, Russell, and Somerset islands and the migrant Boothia Peninsula and Mainland caribou ecotypes had returned from their winter ranges farther south on the mainland to their calving areas and summer ranges on Boothia Peninsula. We treat both caribou ecotypes on Boothia Peninsula as just one geographic population for our assessment. The Arctic-island caribou ecotype on Prince of Wales, Russell, and Somerset islands declined about 98% from the estimated 5097 1+ yr-old caribou in 1980 to fewer than 100 1+ yr-old caribou in 1995 (Gunn & Decker, 1984; Miller, 1997; Gunn & Dragon, 1998; Gunn et al., 2006). This loss of caribou on those islands amounts to a near-total loss of a genetically distinctive group of Arctic-island caribou (e.g., Zittlau, 2004). In contrast, the estimated number of caribou in the geographic population on Boothia Peninsula appeared to increase by 1.4-fold from 4831 to 6658 1+ yr-old caribou between 1985 and 1995, although annual harvesting pressure was heavy. It was biologically impossible for the Boothia Peninsula geographic population at its 1985 estimated size to have persisted until 1995, let alone to have increased, under the estimated average annual harvest regime of 1100 1+ yr-old caribou • yr-1. There is no evidence that the Boothia Peninsula population was underestimated in 1985. It would have required a population in 1985 at least twice as great as the calculated estimate to sustain the estimated annual harvest between 1985 and 1995. An underestimate of such magnitude is too great to be probable. In our examination of the survey results, we could find no reason to question that the calculated population estimates were not reasonable approximations. The fixed-wing aerial surveys in 1980 (Gunn & Decker, 1984), 1985 (Gunn & Ashevak, 1990), and 1995 (Gunn & Dragon, 1998) were highly comparable, well designed and executed, using standard procedures for a fixed-width, strip-transect, systematic aerial survey of caribou. One of the two observers was the same experienced survey biologist in all 3 years, the second observer in 1980 was an experienced survey biologist and in 1985 and 1995 was an experienced Inuit hunter familiar with the area, and the pilot was the same on all surveys and had flown many systematic surveys of caribou on the Canadian Arctic Archipelago and mainland Canada. Helicopter searches of known caribou ranges on Prince of Wales, Russell, and Somerset islands that were carried out in late winter 1996 under ideal viewing conditions yielded only two caribou on Somerset Island and none on Prince of Wales Island or Russell Island (Miller, 1997). In 2004, a combination aerial and ground survey of caribou by the Nunavut Wildlife Service, using a helicopter and snowmobile-mounted Inuit observers, failed to find even one caribou or any recent sign of caribou on Prince of Wales and Somerset islands (Gunn et al., 2006). Gunn et al. (2006) found no evidence that an absolute shortage of forage, relative unavailability of forage due to extreme snow and ice conditions, intraspecific competition with muskoxen (Ovibos moschatus), large-scale emigration, widespread disease, or heavy parasite burdens played a major role in the near-total loss of caribou on Prince of Wales, Russell, and Somerset islands. They did, however, conclude that both wolf (Canis lupus) predation and hunting on Prince of Wales, Russell, and Somerset islands most likely contributed to and deepened the final stage of the decline. The role of annual seasonal migration between the islands and Boothia Peninsula was not considered by Gunn et al. (2006). Therefore, we investigated how annual seasonal migration of the Arctic-island caribou ecotype from Prince of Wales, Russell, and Somerset islands to Boothia Peninsula could have played the major role by providing a yearly ongoing supply of caribou “recruits” on Boothia Peninsula to buffer the heavy annual harvest of caribou there. We carried out a series of multiple analyses of required population structure, required proportion of females producing calves, required proportion of calves surviving to yearlings, allowable annual harvest, and resultant annual harvest shortfall (the number of caribou lost annually at the estimated level of annual harvest or the number of additional caribou required annually from beyond Boothia Peninsula to sustain the annual harvest) in relation to the required size of the 1985 caribou population on Boothia Peninsula. We derived the annual harvest estimates from data presented in Gunn et al. (1986) and Jingfors (1986), which yielded a per capita mean annual harvest of 3.1 caribou • person-1 • yr-1 throughout the Kitikmeot region and at Taloyoak. We believe the extrapolated annual harvest estimates are conservative, as we did not inflate them to account for the 1.6-fold increase in the human population at Taloyoak between 1980 and 1995 and the Inuit hunters did not report any lack of caribou or hardships in obtaining them during that time. Inuit hunters prefer the meat of Arctic-island caribou to that of either the Boothia Peninsula ecotype or the Mainland ecotype. Thus, individuals of the Arctic-island caribou ecotype were shot each winter while they wintered on Boothia Peninsula in preference to both the Boothia Peninsula and the Mainland caribou ecotypes. Although caribou are killed year-round and there is no restriction on how many can be killed, most caribou hunting takes place during winter, when hunters can travel longer distances and haul carcasses back to the settlements more easily by snow machines. Our analyses and assessment of the changes over time in the sizes of the two caribou populations under consideration led us to three primary conclusions. 1) It was biologically impossible for the 4831 1+ yr-old caribou estimated on Boothia Peninsula in 1985 to have sustained the estimated average annual harvest of 1100 1+ yr-old animals for 10 years: the caribou population on the Boothia Peninsula would have been in a steady state of decline and, with the population performing at expected levels, would have been reduced to a remnant or even extirpated as early as 1992. 2) Although the estimated harvest level was unsustainable by the Boothia Peninsula population, the decline was masked by an annual winter infusion of the migrant Arctic-island caribou ecotype from Prince of Wales, Somerset and Russell islands onto Boothia Peninsula during the peak annual hunting period: without the infusion of caribou from the islands, the Inuit of Taloyoak could only have realized, on average, about two-fifths of the estimated annual harvests between 1985 and 1995 without the Boothia Peninsula population entering into a steady state of decline. 3) Migrant Arctic-island caribou from Prince of Wales, Russell, and Somerset islands wintered each year on Boothia Peninsula and this resulted in the persistence of caribou on the Boothia Peninsula, but led to the simultaneous near-demise of the caribou in the Prince of Wales, Russell, and Somerset islands geographic population. The caribou resource within the entire Prince of Wales-Russell-Somerset islands-Boothia Peninsula complex must be managed as a single unit. Effective management is not possible without ongoing assessment of the annual harvest combined with periodic monitoring of population size being carried out on all of those three islands and on Boothia Peninsula at the same times. To date this has not happened. A serious effort should be made to obtain annual harvest statistics yearly and population estimates every 3 years. The interval between population surveys could be stretched to 5 years if the budget demands it, but 6-10 years or more between surveys should be viewed as totally unacceptable. All population surveys should be carried out in July, to obtain population estimate and sex and age composition of the population at the same time during each year and long enough after June calving to get a good measure of the early survival of calves. If any evidence is obtained for large-scale ingress or egress, the population should be surveyed the following July and the magnitude and direction of population change determined and evaluated in relation to current annual harvest estimates. The population should be surveyed the following July after every exceptionally severe winter when a major die-off is probable due to extremely unfavorable snow and ice conditions. All responsible parties (renewable resource agencies and Inuit users) must have the will to act on the findings obtained from the monitoring efforts. Most importantly, they must take the necessary actions in a timely manner, if the findings indicate that the Boothia Peninsula caribou population is in a state of decline. Setting hunting regulations and enforcing harvest limits that are not agreed to by the Inuit users is not practical; therefore, only self-restraint by Inuit hunters will safeguard this valuable renewable caribou resource. The conservation of this hunted caribou population is complicated because preserving only a relatively few caribou is not a satisfactory goal. There must be enough caribou in the population to sustain the desired level of annual harvest or the annual harvest must be quickly adjusted downward to the sustainable level. Otherwise, with a steadily growing human population at Taloyoak, the future of the geographic population of caribou on Boothia Peninsula is not promising and most likely its continual use as a valuable renewable resource is in jeopardy. For further details on this subject see Miller et al. (2007).