Journal articles: 'Desert animals – Adaptation'

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Alemneh, Tewodros. "Adaptation Strategies of Farm Animals to Water Shortage in Desert Areas." American Journal of Biomedical Science & Research 2, no. 6 (May 6, 2019): 245–50. http://dx.doi.org/10.34297/ajbsr.2019.02.000617.

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Gorlov, I. F., G. V. Fedotova, M. I. Slozhenkina, N. I. Mosolova, Ya I. Gishlarkaev, T. A. Magomadov, Yu A. Yuldashbaev, and D. A. Mosolova. "Adaptation features of sheep of the Edilbaev breed reared in the agroecological conditions of the arid zones of Southern Russia." South of Russia: ecology, development 14, no. 3 (October 10, 2019): 71–81. http://dx.doi.org/10.18470/1992-1098-2019-3-71-81.

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Aim. The aim of the research was to study the features of formation of adaptive ability, meat productivity and quality indicators of mutton obtained in the arid conditions of the Volga region from sheep of the Edilbaev breed of different genotypes. Material and Methods. A package of teaching materials has been developed concerning an increase in the productive qualities of different genotypes of the studied breed in the conditions of arid regions of southern Russia. Results. The authors’ research has demonstrated the high adaptive abilities of animals of the Edilbaev breed, their economic and biological qualities, food and taste indicators of their meat, as well as the possibility of further development of the breed in the arid conditions of southern Russia. As a research base, we selected the Volgograd‐Edilbay LLC breeding farm (the world's only breeding and genetic center for raising Edilbaev sheep) which is located in the Volgograd region and specializes in breeding pure‐bred animals in arid steppe, semi‐desert and desert zones. Due to the great demand for the livestock of this breed from farms located in arid territories, this study of the comparative aspects of production characteristics of animals of original and new types in the arid conditions of the Volga region is of interest to both science and practical animal husbandry. Conclusion. An assessment of the nutritional value of mutton obtained from animals of the Edilbaev breed has shown its high nutritional and biological qualities.

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Choshniak, I., N. Ben-Kohav, C. R. Taylor, D. Robertshaw, R. J. Barnes, A. Dobson, V. Belkin, and A. Shkolnik. "Metabolic adaptations for desert survival in the Bedouin goat." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 268, no. 5 (May 1, 1995): R1101—R1110. http://dx.doi.org/10.1152/ajpregu.1995.268.5.r1101.

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Energy conservation is a key adaptation for desert survival in the Bedouin goat. When food is scarce, metabolism is reduced and body weight can be maintained indefinitely on less than one-half of normal intake. We hypothesized that metabolism would be turned down during both rest and exercise, but it was not. It was low when animals rested and returned to normal during exercise. We expected catecholamines and thyroid hormones would modulate metabolism, but they did not. The reduction in metabolism preceded any change in thyroid hormone concentrations, and infusions of epinephrine did not restore reduced metabolism to normal levels. Finally, we expected the gut would be the major organ system involved in the metabolic reduction because less food is eaten, processed, and absorbed. Contrary to our expectations, we found that muscle is the primary organ system responsible for the reduction. It appears that the adaptations of the Bedouin goat for surviving on limited food supplies involve different organ systems and different modulators to reduce metabolism from those known for other mammals.

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El-Hadi, H. M. "The effect of dehydration on Sudanese desert sheep and goats." Journal of Agricultural Science 106, no. 1 (February 1986): 17–20. http://dx.doi.org/10.1017/s0021859600061657.

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SUMMARYChanges in body weight and body temperature were observed in Sudanese desert sheep and goats, which had been subjected to the summer sun (20 °C min. to 42 °C max.), given water normally and then deprived of water for 3 days. Tritiated water was also used to measure total body water and water turnover in these animals together with measurements of plasma and extracellular space, intracellular fluid volume and blood osmolality. The body weight and the size of the fluid compartments decreased in the two species at varying degrees associated with haemoconcentration. The extent of some changes was more marked in sheep than in goats, suggesting better adaptation of the former species to desert life.

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Woodward, Matthew A., and Metin Sitti. "Morphological intelligence counters foot slipping in the desert locust and dynamic robots." Proceedings of the National Academy of Sciences 115, no. 36 (August 22, 2018): E8358—E8367. http://dx.doi.org/10.1073/pnas.1804239115.

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During dynamic terrestrial locomotion, animals use complex multifunctional feet to extract friction from the environment. However, whether roboticists assume sufficient surface friction for locomotion or actively compensate for slipping, they use relatively simple point-contact feet. We seek to understand and extract the morphological adaptations of animal feet that contribute to enhancing friction on diverse surfaces, such as the desert locust (Schistocerca gregaria) [Bennet-Clark HC (1975) J Exp Biol 63:53–83], which has both wet adhesive pads and spines. A buckling region in their knee to accommodate slipping [Bayley TG, Sutton GP, Burrows M (2012) J Exp Biol 215:1151–1161], slow nerve conduction velocity (0.5–3 m/s) [Pearson KG, Stein RB, Malhotra SK (1970) J Exp Biol 53:299–316], and an ecological pressure to enhance jumping performance for survival [Hawlena D, Kress H, Dufresne ER, Schmitz OJ (2011) Funct Ecol 25:279–288] further suggest that the locust operates near the limits of its surface friction, but without sufficient time to actively control its feet. Therefore, all surface adaptation must be through passive mechanics (morphological intelligence), which are unknown. Here, we report the slipping behavior, dynamic attachment, passive mechanics, and interplay between the spines and adhesive pads, studied through both biological and robotic experiments, which contribute to the locust’s ability to jump robustly from diverse surfaces. We found slipping to be surface-dependent and common (e.g., wood 1.32 ± 1.19 slips per jump), yet the morphological intelligence of the feet produces a significant chance to reengage the surface (e.g., wood 1.10 ± 1.13 reengagements per jump). Additionally, a discovered noncontact-type jump, further studied robotically, broadens the applicability of the morphological adaptations to both static and dynamic attachment.

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Aboul-Naga, A., Mona A. Osman, V. Alary, F. Hassan, I. Daoud, and J. F. Tourrand. "Raising goats as adaptation process to long drought incidence at the Coastal Zone of Western Desert in Egypt." Small Ruminant Research 121, no. 1 (September 2014): 106–10. http://dx.doi.org/10.1016/j.smallrumres.2014.02.009.

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Aboul Naga, A. M., T. M. Abdel Khalek, Mona Osman, A. R. Elbeltagy, E. S. Abdel-Aal, F. F. Abou-Ammo, and M. H. El-Shafie. "Physiological and genetic adaptation of desert sheep and goats to heat stress in the arid areas of Egypt." Small Ruminant Research 203 (October 2021): 106499. http://dx.doi.org/10.1016/j.smallrumres.2021.106499.

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Harris, Zechariah C., and Jonathan C. Wright. "The physiology of Venezillo arizonicus (Isopoda, Armadillidae): metabolism and thermal tolerance." Crustaceana 94, no. 2 (February 15, 2021): 159–75. http://dx.doi.org/10.1163/15685403-bja10026.

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Abstract Venezillo arizonicus (Mulaik & Mulaik, 1942) is the only oniscidean isopod native to the Southwest Desert Province of North America. In accordance with its desert habitat, we hypothesized that V. arizonicus would have a higher upper lethal temperature than mesic oniscideans. If oniscidean thermal tolerance is limited by an oxygen consumption-uptake mismatch (physiological hypoxia), as indicated by recent work with other land isopods, we further hypothesized that V. arizonicus would possess highly efficient pleopodal lungs, as defined by its capacity for metabolic regulation in reduced . Other adaptations to counter oxygen limitation at high temperatures could include reduced temperature sensitivity of metabolism (low ) and an overall reduction in metabolic rate. Thermal tolerance was measured using the progressive method of Cowles & Bogert and the catabolic rate of animals () was measured as a function of temperature and . The critical thermal maximum (CTmax) of winter-acclimatized animals was 43.0 ± 0.85°C, 1.6-2.6°C higher than published values for summer-acclimatized mesic oniscideans. The catabolic rate at 25°C was 1.50 ± 0.203 μl min−1 g−1, markedly lower than values determined for mesic Oniscidea (4-6 μl min−1 g−1) and was unaffected by hypoxia as low as 2% O2 (ca. 2 kPa). Catabolism was, however, quite sensitive to temperature, showing a mean of 2.58 over 25-42°C. The efficient pleopodal lungs and low metabolic rate of V. arizonicus will both tend to mitigate physiological hypoxia, consistent with the species’ high CTmax. A low catabolic rate may also be an adaptation to low habitat productivity and seasonally constrained activity patterns.

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Buret, A., J. Hardin, M. E. Olson, and D. G. Gall. "Adaptation of the small intestine in desert-dwelling animals: Morphology, ultrastructure and electrolyte transport in the jejunum of rabbits, rats, gerbils and sand rats." Comparative Biochemistry and Physiology Part A: Physiology 105, no. 1 (May 1993): 157–63. http://dx.doi.org/10.1016/0300-9629(93)90189-b.

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Sambyla, Ch N., N. M. Bessonova, and R. B. Chysyma. "Natural resistance of marals of Altai-Sayan breed during the process of adaptation under the environments of the Republic of Tyva." Glavnyj zootehnik (Head of Animal Breeding), no. 9 (September 1, 2020): 41–49. http://dx.doi.org/10.33920/sel-03-2009-05.

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The Republic of Tyva is a region in the geographical center of Asia, which located at the junction of the Siberian taiga and Central Asian desert-steppe landscapes, in a wide band of mountains and intermountain plains. The mountain-forest area of Tyva has long been considered a natural habitat for antler deer, one of which is the maral (Cervus elaphus sibiricus). In order to restore maral breeding and increase the number of marals in the former limits, marals of the Altai-Sayan breed have been imported to the Republic of Tyva from the Republic of Altai. The preservation of productive traits, reproductive function and the realization of the genetic potential of animals introduced to new climatic conditions largely depends on the ability of these animals to adapt to existing environments. We have assessed in this paper the natural resistance of the marals of Altai-Sayan breed during introduction in the Tyva Republic in comparison with the indicators of the marals have been bred in the Altai Republic. The researches have been carried out in 2019. The research material was blood samples of marals of Altai-Sayan breed imported to the Republic of Tuva (n=27) and marals of the same breed bred in the Republic of Altai (n=17). Studies have shown some deviations in the blood leukogram of imported marals, such as a decrease in the number of eosinophils and rod nuclear neutrophils (P < 0,001), the increase in the number of segmented nuclear neutrophils and lymphocytes (P < 0,05). The number of monocytes have been increased in 18,6 times compared to the Altai marals. The change in the number of monocytes exceeded the physiological norm by 24,7 %. The indicator of adaptation evaluation in imported marals had higher values (6,8), which were in 1,7 times higher than in marals bred in the Altai Republic (4,1), which indicates the intensity of adaptive mechanisms in imported animals during adaptation. Analysis of phagocytic activity and phagocytic index revealed intensive phagocytosis in imported marals: phagocytic activity – by 12,4 % (P < 0,05), phagocytic index – by 5,1 %, and the increase in the content of lysosomal and cationic proteins by 12,8 % (P < 0,05). Analysis of the bactericidal activity of blood serum has shown its lower level in imported animals (45,97±1,36 %), compared with marals of the same breed bred in the Altai Republic (52,19±2,15 at P < 0,05). Thus, according to most indicators of natural resistance marals of Altai-Sayan breed imported to Tyva have a fairly high level of natural protection, which indicates that they can be adapted to the natural climatic and feeding conditions of the Republic of Tyva.

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Kerley, GIH, and WG Whitford. "Desert-Dwelling Small Mammals as Granivores - Intercontinental Variations." Australian Journal of Zoology 42, no. 4 (1994): 543. http://dx.doi.org/10.1071/zo9940543.

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Deserts are, by definition, environmentally similar, and this has lead to hypotheses of convergence in the properties of desert biotic communities as well as the components of these communities. There is considerable evidence for convergence in some characteristics of desert biota, ranging from plant growth forms to the well-known bipedal, nocturnal rodents. One area that has received considerable attention has been granivory by desert rodents, largely because of the effort focused on the North American desert heteromyids, and also because the process of granivory has far-reaching ramifications for desert plant communities. Specific tests for convergence in the impact of rodents as granivores, by means of bait-removal experiments, however, have shown that the high levels of seed removal by rodents in the North American deserts differs from that of rodents in the South American, Australian and South African deserts, where ants are the most important seed harvesters. The only studies to measure the impact of rodents on desert seed fluxes confirm these patterns, with rodents consuming up to 86% of seed production in North American deserts, but less than 1% of seed production in South African deserts. A review of dietary data for desert rodents confirms these trends, with little evidence for the presence of granivores in deserts besides those of North America. A variety of hypotheses have attempted to explain these variations in desert rodent granivory. These include recent extinctions of granivores, that seed burial, low soil nutrients and/or limiting seed production prevented the radiation of granivorous small mammals, and that particular deserts are too young or too recently colonised by rodents for granivorous rodents to have evolved. However, none of these hypotheses are supported by available evidence. Alternative hypotheses suggesting that climate variability may have precluded the development of specialised granivores need to be tested. In particular, more data are needed to confirm these patterns of granivory, and gain an understanding of the effects of Pleistocene and recent desert climate variability on seed production. An alternative perspective suggests that the presence of the heteromyid rodents may explain the high levels of granivory by small mammals in North American deserts. The variability in granivory by small mammals between deserts suggests that deserts will also differ in terms of anti-granivore adaptations of plants, seed fluxes and the mechanisms whereby small mammals coexist.

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CIoudsley-Thompson, J. L. "Successful Desert Animals — Scorpions, Beetles and Lizards." Libyan Studies 24 (1993): 143–56. http://dx.doi.org/10.1017/s0263718900002016.

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AbstractWhereas the reactions of animals to heat are largely behavioural, responses to water shortage are primarily physiological. These characters are exhibited in all terrestrial biomes, but are enhanced in the desert. Desert animals, in general, are either cryptically sand-coloured or else black when distasteful or poisonous. This applies to all three taxa under discussion; most beetles are black, most lizards cryptic. Scorpions, paradoxically, may be either black or cryptic. Examples of mimicry and protective resemblance are also cited. It is concluded that scorpions, beetles and lizards are especially successful desert animals, not so much on account of unique adaptations to the harsh and variable environment as to their innate qualities which have adapted them for life in hot, dry and unpredictable habitats.

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Crawford, Clifford S. "Animal adaptations and ecological processes in desert dunefìelds." Journal of Arid Environments 21, no. 2 (September 1991): 245–60. http://dx.doi.org/10.1016/s0140-1963(18)30685-2.

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Parvizi, Omid, Hosny El-Adawy, Uwe Roesler, Heinrich Neubauer, and Katja Mertens-Scholz. "Performance Analysis of Anaplasma Antibody Competitive ELISA Using the ROC Curve for Screening of Anaplasmosis in Camel Populations in Egypt." Pathogens 9, no. 3 (February 27, 2020): 165. http://dx.doi.org/10.3390/pathogens9030165.

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Anaplasmosis is a tick-born and potential zoonotic disease caused by Anaplasma (A.) phagocytophilum, A. ovis, A. platys and A. capra. Anaplasma marginale affecting bovines and camels causing significant economic losses. Camels as an integral part of the socio-economic lifestyle of nomads in semi-arid to arid ecosystems are prone to suffer from subclinical Anaplasma infections. This study aimed to determine the performance and adaptation of commercial competitive Anaplasma ELISA (cELISA) as a tool for screening the seroprevalence of anaplasmosis whitin the camel populations in Egypt. This study was based on the serological investigation of 437 camel sera collected between 2015 and 2016 during a Q fever prevalence study in Egypt using commercially available cELISA for the detection of antibodies specific for Anaplasma in bovine serum. The receiver operating characteristic (ROC) curve, an analysis method for optimizing cutoff values in cELISAs, was used to estimate the sensitivity and specificity using 76 true as serological positive (n = 7) and negative (n = 60) for Anaplasma antibodies. ROC curve analysis was done for 7 true positive and 60 true negative bovine samples and 7 true positive and 29 true negative camel samples serum. Real time PCR and/or conventional PCR was applied to confirm Anaplasma spp. specific-DNA in camel serum as an indication of a true positive and true negative for ROC analysis. Chi square analysis was performed to estimate the association between risk factors and anaplasmosis in camels. The cutoff value was determined as 0.42 (p value ≤ 0.001). Data simulation with randomly generated values revealed a cutoff value of 0.417 (p ≤ 0.001) with resulting 58.1% Se and 97.8% Sp. Seven true positive and 29 true negative camel serum samples was confirmed by PCR. Using the estimated cut off, the seroprevalence in the Nile Valley and Delta and the Eastern Desert domain was 47.4% and 46.4%, respectively. The potential risk factors as domains and origin of animals were less significantly associated with the prevalence of anaplasmosis (domains: χ(2) = 41.8, p value ≤ 0.001 and origin: χ(2) = 42.56, p value ≤ 0.001). Raising awareness especially for veterinarians and animal owners will significantly contribute to the best understanding of anaplasmosis in camels in Egypt. Alternative (in silico) validation techniques and preliminary prevalence studies are mandatory towards the control of neglected anaplasmosis in the camel population.

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TAGHVAEI, M., H. SADEGHI, and N. KHAEF. "CARDINAL TEMPERATURES FOR GERMINATION OF THE MEDICINAL ANDDESERT PLANT, Calotropis procera." Planta Daninha 33, no. 4 (December 2015): 671–78. http://dx.doi.org/10.1590/s0100-83582015000400005.

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ABSTRACT Calotropis procera, Apocynaceae, is a wild perennial shrub that originated in the Persian deserts. It is known to provide key resources in degraded ecosystems to about 80 animal species. C. procera is regenerated by seed and produces lots of small seeds that are dispersed by wind; nonetheless, its density is very low. The purpose of this study is to estimate the cardinal temperatures including the base, optimum, and maximum temperatures of Calotropis procera looking at two different ecotypes in the Iranian desert. The germination behavior of C. procera seeds was tested at temperature regimens of 0, 5, 10, 15, 20, 25, 30, 35 and 40oC and was analyzed using linear regression models. The rate of germination increased between base and optimum thermal conditions, and decreased between optimum and maximum thermal conditions. The base, optimum and maximum temperatures for germination of C. procera seeds were estimated at 19.10, 30.75 and 47.80 oC for the Fars and 20.00, 31.82 and 49.69oC for the Zahedan desert, respectively. Temperature and germination were rated to determine the seeding dates of the C. procera. Overall, cardinal temperatures for germination were dependent on local climate characteristics for the range of adaptations in plant growth of the given species.

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Predavec, Martin. "Variable Energy Demands in Pseudomys hermannsburgensis: Possible Ecological Consequences." Australian Journal of Zoology 45, no. 1 (1997): 85. http://dx.doi.org/10.1071/zo96062.

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The energy metabolism of Pseudomys hermannsburgensis, a native Australian desert rodent, was investigated with animals captured in the field. Animals showed large variation in basal metabolic rate between two time periods [November 1991 (1·40 ± 0·38 mL 0 2 g-1 h-1 ) and September 1992 (3·58 ± 0·24)], producing values that generally differed from those predicted from body mass. P. hermannsburgensis also entered torpor, which has not been demonstrated previously in an Australian rodent. Environmental stimuli for changes in metabolic rates are not clear. Possible ecological advantages of the observed patterns of energy metabolism are conservation of energy and water and increased longevity. All three factors may be considered adaptations to the variable desert environment.

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Randall, Jan A. "Behavioural adaptations of desert rodents (Heteromyidae)." Animal Behaviour 45, no. 2 (February 1993): 263–87. http://dx.doi.org/10.1006/anbe.1993.1032.

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Tinsley, R. C. "Parasite adaptation to extreme conditions in a desert environment." Parasitology 119, S1 (December 1999): S31—S56. http://dx.doi.org/10.1017/s0031182000084638.

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SUMMARYDeserts represent universally recognized extreme environments for animal life. This paper documents the highly specialized adaptations of Pseudodiplorchis americanus, a monogenean parasite of the desert toad, Scaphiopus couchii. Building on a long-term record of parasite population ecology (continuing since the early 1980s), field studies focus on the effects of severe drought in the Sonoran Desert, Arizona, in the mid 1990s. This provides a test of the ability of the host-parasite system to tolerate exceptional perturbation. The analysis provides new insight into parasite infection dynamics in a natural wildlife system through integration of host and parasite population age structure. The environmental check interrupted host recruitment in 1993–95 and parasite recruitment in 1995–97. This produced an imprint in age structure and infection levels recognizable over several years: parasite recruitment failure reduced transmission 2–3 years later. The host (maximum life span 17 years) tolerated the disruption but the impact was more serious for the parasite (life span 3 years) leading to extinction of some previously stable populations. Despite this demonstration of a rare event exacerbating external environmental constraints, experimental studies suggest that the internal (host) environment normally creates the most severe conditions affecting P. americanus. Only about 3 % of parasites survive from invasion until first reproduction. Post-invasion factors including host immunity, characteristic of most parasite life cycles, constitute a greater constraint upon survival than external conditions, even in a desert environment.

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Dickman, Christopher R., and Libby Robin. "Putting Science in its Place: The Role of Sandringham Station in Fostering Arid Zone Science in Australia." Historical Records of Australian Science 25, no. 2 (2014): 186. http://dx.doi.org/10.1071/hr14014.

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For the past fifty years, Sandringham Station has provided a major focus for scientific work in southwestern Queensland, an arid region that includes the Simpson Desert and the Channel Country (together 'Desert Channels'). This paper explores the role of place, chance and private enterprise in supporting science in this region. Unlike other parts of inland Australia, where government initiatives were prominent, science in Queensland's arid country was privately supported, and research there had an ecological or eco-physiological rather than an economic focus. It began later than elsewhere (1960s), and its scientific questions were different from those framed in research stations set up to address agricultural and pastoral imperatives. The location of Sandringham on the ecological edge between the ephemeral wetlands of the anastomosing channels and the dune country of the Simpson Desert created an ecotonal area that was rich in animals adapted to living in Australian desert country, and a particular opportunity to observe their adaptations to the boom-and-bust ecological conditions. The role of local observers, particularly station managers and naturalists, has been critical in studying the often cryptic animals of the region, and the ongoing support of the station itself was essential to investigations that were mostly on private leasehold lands.

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Ślipiński, Piotr, Jan Jakub Pomorski, and Katarzyna Kowalewska. "Heat shock proteins expression during thermal risk exposure in the temperate xerothermic ant Formica cinerea." Sociobiology 62, no. 3 (September 30, 2015): 457. http://dx.doi.org/10.13102/sociobiology.v62i3.409.

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The abiotic conditions of the desert habitat fluctuate in a circadian rhythm of hot days and cold nights. Species living in desert habitats evolved many adaptations to increase their chances of survival. However, abiotic conditions in xerothermic habitats of a temperate climate are much different. Diurnal fluctuations are not as strong, but animals have to cope with seasonal changes and hibernate during the winter, which may potentially influence their adaptations to critical temperature conditions. We attempted to assess heat resistance adaptations using the example of a widely distributed xerothermic ant Formica cinerea. Using Real-Time PCR, we measured the expression of three heat shock protein genes (Hsp60, Hsp75, Hsp90) and assessed the adaptations of F. cinerea to enable foraging in risk prone conditions. The analysis of gene expression using the Generalized Linear Model surprisingly indicated that there was no significant effect of temperature when comparing workers from the control (23ºC) with workers foraging on the surface of hot sand (47-54ºC). As a next step we tried to estimate the threshold of a thermal resistance with the use of thermal chambers. Expression of all Hsps genes increase compare to the control group, expression of Hsp60 and Hsp90 continued up to 45ºC.

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Wang, D., and L. Ba. "Ecology of meadow steppe in northeast China." Rangeland Journal 30, no. 2 (2008): 247. http://dx.doi.org/10.1071/rj08005.

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Native grassland in China is mostly meadow, typical or desert steppe and comprises 400 million hectares, ~40% of the land area. We review past research on the meadow steppe of north-east China. Our foci are plant adaptation to climate, edaphic-related and defoliation stresses, vegetation production, grassland management, herbivore foraging behaviour, safe stocking rates, plant-animal interactions, ecosystem functioning, conservation of biodiversity and the influence of climate change on grassland function. Recent studies have provided some insights into ecological processes and functioning of meadow steppe, and have enabled better identification of research opportunities. Key areas identified for future research include plant adaptation, grassland function and value, monitoring of range health, ecological consequences of climate change on biodiversity and ecosystem function.

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Toolson, Eric C. "Water Profligacy as an Adaptation to Hot Deserts: Water Loss Rates and Evaporative Cooling in the Sonoran Desert Cicada, Diceroprocta apache (Homoptera: Cicadidae)." Physiological Zoology 60, no. 4 (July 1987): 379–85. http://dx.doi.org/10.1086/physzool.60.4.30157899.

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Rocha, P. L. B., S. Renous, A. Abourachid, and E. Höfling. "Evolution toward asymmetrical gaits in Neotropical spiny rats (Rodentia: Echimyidae): evidences favoring adaptation." Canadian Journal of Zoology 85, no. 6 (June 2007): 709–17. http://dx.doi.org/10.1139/z07-049.

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The torch tail rat, Trinomys yonenagae Rocha, 1995 (family Echimyidae), is the morphologically most divergent of the spiny rats. In this study, we evaluate the hypothesis that gaits preferentially used by this species evolved as an adaptation to the desert-like dunes where they live. We filmed spontaneous locomotion of T. yonenagae, Trinomys albispinus minor Reis and Pessôa, 1995, and Proechimys cayennensis (Desmarest, 1817) with a high-speed camera. We detected, for each of the 323 cycles of the reference forelimb recorded, the kind of gait developed, the time lags between the touchdown of each pair of limbs, and the relative velocity. Trinomys yonenagae walked twice as fast as P. cayennensis and T. a. minor using mainly the asymmetrical transverse gallop, half-bounds, and bounds, while the other two species used mainly the lateral sequence walk. Gaits changed from symmetrical to asymmetrical with increasing velocity for T. yonenagae but not for the other species. We argue that the gait pattern found in T. yonenagae is autapomorphic, that its origin coincides with the shift to a desert-like habitat, and that this type of gait confers higher adaptive value to explore resources in open areas than the plesiomorphic pattern. Therefore, we conclude that it can be considered adaptive to life in the dunes.

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Aricha, Han, Huasai Simujide, Chunjie Wang, Jian Zhang, Wenting Lv, Xirnud Jimisi, Bo Liu, et al. "Comparative Analysis of Fecal Microbiota of Grazing Mongolian Cattle from Different Regions in Inner Mongolia, China." Animals 11, no. 7 (June 29, 2021): 1938. http://dx.doi.org/10.3390/ani11071938.

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Mongolian cattle from China have strong adaptability and disease resistance. We aimed to compare the gut microbiota community structure and diversity in grazing Mongolian cattle from different regions in Inner Mongolia and to elucidate the influence of geographical factors on the intestinal microbial community structure. We used high throughput 16S rRNA sequencing to analyze the fecal microbial community and diversity in samples from 60 grazing Mongolian cattle from Hulunbuir Grassland, Xilingol Grassland, and Alxa Desert. A total of 2,720,545 high-quality reads and sequences that were 1,117,505,301 bp long were obtained. Alpha diversity among the three groups showed that the gut microbial diversity in Mongolian cattle in the grasslands was significantly higher than that in the desert. The dominant phyla were Firmicutes and Bacteroidetes, whereas Verrucomicrobia presented the highest abundance in the gut of cattle in the Alxa Desert. The gut bacterial communities in cattle from the grasslands versus the Alxa Desert were distinctive, and those from the grasslands were closely clustered. Community composition analysis revealed significant differences in species diversity and richness. Overall, the composition of the gut microbiota in Mongolian cattle is affected by geographical factors. Gut microbiota may play important roles in the geographical adaptations of Mongolian cattle.

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Gahji, A., A. O. Adegwa, and A. O. Adegwa. "THE SIGNIFICANCE OF CAMEL PRODUCTION IN NIGERIA." Nigerian Journal of Animal Production 13 (January 16, 2021): 29–35. http://dx.doi.org/10.51791/njap.v13i.2380.

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Aspect of camel. distribution, adaptations and utilisation. m Nigeria have been reviewed and a suggestion made for a scientific and profitable camel production to ease the deficiency of animal protein in the Nigerian diet. This is necessitated because the encro achment of the desert into the Northern part of the country strongly calls for the reassessment of the potential contribution of camel production as source of meat and milk to provide not only essential protein source in the Nigerian diet, but also saving on the scarce foreign exchange.

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Dirks, Inga, Buzi Raviv, Oren Shelef, Amber Hill, Eppel Amir, Moses Kwame Aidoo, Brian Hoefgen, et al. "Green roofs: what can we learn from desert plants?" Israel Journal of Ecology and Evolution 62, no. 1-2 (April 12, 2016): 58–67. http://dx.doi.org/10.1080/15659801.2016.1140619.

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Green roofs in the Mediterranean region are often exposed to high levels of radiation, extreme temperatures, and an inconsistent water supply. To withstand these harsh conditions in shallow soils and poorly aerated growth media, plants must be armored with adaptations. Strategies that have evolved in desert plants can play significant roles in the use of plants for green covers. In the following, we will specifically focus on (1) heat and radiation, (2) drought, and (3) salinity. Further, we will discuss (4) interactions between neighboring plants. Finally, we will (5) propose a design for diverse green roofs that includes horticultural and medicinal products and provides diverse habitats. Many desert plants have developed morphological and anatomical features to avoid photo-inhibition, which can be advantageous for growth on green roofs. Plants exhibiting C4photosynthesis or crassulacean acid metabolism (CAM) photosynthesis have a protected hydraulic system that enables growth under dry conditions. Furthermore, dew and high levels of relative humidity can provide reliable water sources under limited precipitation. Halophytes are protected against salinity, ionic specific stress, and nutritional imbalances, characteristics that can be advantageous for green roofs. Under limited space, competition for resources becomes increasingly relevant. Allelopathy can also induce the germination and growth inhibition of neighboring plants. Many desert plants, as a result of their exposure to environmental stress, have developed unique survival adaptations based on secondary metabolites that can be used as pharmaceuticals. A systematic survey of plant strategies to withstand these extreme conditions provides a basis for increasing the number of green roof candidates.

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Bornstein, S. "The ship of the desert. The dromedary camel (Camelus dromedarius), a domesticated animal species well adapted to extreme conditions of aridness and heat." Rangifer 10, no. 3 (September 1, 1990): 231. http://dx.doi.org/10.7557/2.10.3.860.

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The dromedary camel (Camel dromedarius) is extremely well adapted to life in hot and arid lands. In terms of physiological adaptation to heat and water deprivation it surpasses by far every other large animal of which data have been collected. None of the adaptive mechanisms to cope with the environmental stresses are unique to the Arabian camel, but the efficiency of its adaptation is superior. At high ambient temperatures the camels adapt to the scarcity of water by reducing their faecal, urinary and evaporative water losses. During dehydration, the kidneys reduce water losses both by decreasing the glomerual filtration rate and by increasing the tubular reabsorption of water. Also their ability of regulating their body temperature from 34.5-40.7 °C conserves a lot of water, when most needed.

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Kronfeld, N., and A. Shkolnik. "Adaptation to Life in the Desert in the Brown Hare (Lepus capensis)." Journal of Mammalogy 77, no. 1 (February 16, 1996): 171–78. http://dx.doi.org/10.2307/1382718.

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Farley, Roger D. "Matrotrophic adaptations and early stages of embryogenesis in the desert scorpionParuroctonus mesaensis (Vaejovidae)." Journal of Morphology 237, no. 3 (September 1998): 187–211. http://dx.doi.org/10.1002/(sici)1097-4687(199809)237:3<187::aid-jmor1>3.0.co;2-x.

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Tingle, Jessica L. "Facultatively Sidewinding Snakes and the Origins of Locomotor Specialization." Integrative and Comparative Biology 60, no. 1 (April 26, 2020): 202–14. http://dx.doi.org/10.1093/icb/icaa011.

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Abstract Specialist species often possess adaptations that strongly distinguish them from their relatives, obscuring the transitional steps leading to specialization. Sidewinding snakes represent an example of locomotor specialization in an elongate, limbless terrestrial vertebrate. We typically think of sidewinding as a gait that only a handful of very specialized snake species perform, mostly vipers from sandy desert environments. Some of these desert-dwelling vipers are so specialized that they only rarely use more common types of locomotion. However, some non-viper species sidewind facultatively in particular circumstances, and a few may regularly sidewind under natural conditions. Numerous accounts report facultative sidewinding in species that more typically perform other types of locomotion. I have compiled these accounts, uncovering evidence that dozens of species perform sidewinding with varying proficiency under a variety of conditions. These facultative sidewinders can reveal insight into the evolution and biomechanics of sidewinding, and they provide ample opportunities for future study.

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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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Guerra, Carlos G., Roberto E. Aguilar, and Lloyd C. Fitzpatrick. "Water Vapor Conductance in Gray Gulls (Larus modestus) Eggs: Adaptation to Desert Nesting." Colonial Waterbirds 11, no. 1 (1988): 107. http://dx.doi.org/10.2307/1521176.

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Murray, Ian W., and Felisa A. Smith. "Estimating the influence of the thermal environment on activity patterns of the desert woodrat (Neotoma lepida) using temperature chronologies." Canadian Journal of Zoology 90, no. 9 (September 2012): 1171–80. http://dx.doi.org/10.1139/z2012-084.

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Environmental temperature influences the ecology and life history of animals. In habitats near the thermal range boundary, fluctuations in temperature may influence the ability of species to persist. Desert woodrats ( Neotoma lepida Thomas, 1893) occupy one of the hottest and most extreme environments in the western hemisphere, Death Valley, California, despite limited adaptations for water conservation or efficient heat dissipation. Moreover, N. lepida have a relatively low tolerance for high temperature. Thus, we hypothesized temperature might influence both the timing and the duration of activity. To test this idea, we attached iButton sensors to 56 animals over a 2-year period and recorded activity. Each sensor was set to record at 5 or 15 min intervals and stored approximately 2000 records before retrieval. We found a strong relationship between ambient temperature and onset and duration of activity, influenced by both body size and gender. Neotoma lepida did not emerge until air temperature fell below 42 °C. As daily high temperatures increased, both sexes had fewer nightly activity bouts of shorter duration. Our results suggest that activity of N. lepida is constrained during the climatically intense summer months. Animals face a trade-off between remaining in the thermal safety of the den vs. emerging to obtain resources.

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Mastrangelo, S., B. Moioli, A. Ahbara, S. Latairish, B. Portolano, F. Pilla, and E. Ciani. "Genome-wide scan of fat-tail sheep identifies signals of selection for fat deposition and adaptation." Animal Production Science 59, no. 5 (2019): 835. http://dx.doi.org/10.1071/an17753.

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Fat tail in sheep represents a valuable energy reserve for facing future climate changes. The identification of genes with a role in the fat-tail phenotype may contribute to understanding the physiology of fat deposition and the mechanisms of adaptation. Genotypic data obtained with the OvineSNP50K array in 13 thin-tail sheep breeds from Italy were used to identify selection signatures of fat tail through pairwise thin- versus fat-tail sheep breed comparisons, with the following fat-tail breeds of the Mediterranean area: two unique Italian fat-tail breeds (Barbaresca and Laticauda), a Barbary sheep breed from Libya, Ossimi breed from Egypt, Cyprus Fat-Tail and Chios from the Greek islands Cyprus and Chios, respectively. Fst and χ2 values obtained for >40000 polymorphic markers allowed confirmation of 12 fat-tail associations that were previously reported in Chinese and Iranian breeds. Two of these signals – on OAR 7 and OAR 13 – are in the proximity of two genes – VRTN and BMP2 – with a role in the variation of vertebral number and in fat-tail formation respectively. Two identified signals on OAR 6 and OAR 15 encompass two genes, PDGFRA and PDGFD, involved in the differentiation of preadipocytes. Further signals detected herein were reported in Chinese sheep as signatures of adaptation to desert areas. For several of the detected associations, the known role in either fat deposition or adaptation, thus contributing to revealing the molecular basis underlying mechanisms of energy storage and climate adaptation.

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Altshuler, Douglas L., Joseph W. Bahlman, Roslyn Dakin, Andrea H. Gaede, Benjamin Goller, David Lentink, Paolo S. Segre, and Dimitri A. Skandalis. "The biophysics of bird flight: functional relationships integrate aerodynamics, morphology, kinematics, muscles, and sensors." Canadian Journal of Zoology 93, no. 12 (December 2015): 961–75. http://dx.doi.org/10.1139/cjz-2015-0103.

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Bird flight is a remarkable adaptation that has allowed the approximately 10 000 extant species to colonize all terrestrial habitats on earth including high elevations, polar regions, distant islands, arid deserts, and many others. Birds exhibit numerous physiological and biomechanical adaptations for flight. Although bird flight is often studied at the level of aerodynamics, morphology, wingbeat kinematics, muscle activity, or sensory guidance independently, in reality these systems are naturally integrated. There has been an abundance of new studies in these mechanistic aspects of avian biology but comparatively less recent work on the physiological ecology of avian flight. Here we review research at the interface of the systems used in flight control and discuss several common themes. Modulation of aerodynamic forces to respond to different challenges is driven by three primary mechanisms: wing velocity about the shoulder, shape within the wing, and angle of attack. For birds that flap, the distinction between velocity and shape modulation synthesizes diverse studies in morphology, wing motion, and motor control. Recently developed tools for studying bird flight are influencing multiple areas of investigation, and in particular the role of sensory systems in flight control. How sensory information is transformed into motor commands in the avian brain remains, however, a largely unexplored frontier.

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Hardwick, Kayla M., Jeanne M. Robertson, and Erica Bree Rosenblum. "Asymmetrical mate preference in recently adapted White Sands and black lava populations of Sceloporus undulatus." Current Zoology 59, no. 1 (February 1, 2013): 20–30. http://dx.doi.org/10.1093/czoolo/59.1.20.

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Abstract Speciation can proceed rapidly when natural and sexual selection act in concert. For example speciation can be accelerated when traits that confer a selective advantage in a particular habitat also influence mate preference. Studying parallel but evolutionarily independent instances of ecological divergence can illuminate the interaction between natural and sexual selection during speciation. Locally adapted populations of the eastern fence lizard Sceloporus undulatus have recently evolved in three different habitats in the Chihuahuan desert: blanched color morphs occur on the gypsum dunes of White Sands, melanic color morphs occur on the Carrizozo lava flow, and brown color morphs occur in the surrounding desert scrubland. In addition to differences in cryptic dorsal coloration, populations also differ in the size and color of ventral patches used for social signaling. This system therefore provides an opportunity to investigate the interplay of natural and sexual selection during rapid ecological speci-ation. We used mate preference experiments to determine whether locally adapted populations may exhibit the early stages of behavioral reproductive isolation. We observed an asymmetrical mate preference in this system; White Sands males preferentially courted local females, while males from dark soils and black lava populations did not exhibit a preference for local mates. We also found that female behavior and ventral patch phenotype were associated with male courtship. Our results suggest that the observed preference for local mates evolved at White Sands, and we discuss the possible link between local adaptation and traits involved in mate preference in this system.

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Camargo, Issac, and Sergio Ticul Álvarez-Castañeda. "Analyses of predation behavior of the desert shrew Notiosorex crawfordi." Mammalia 83, no. 3 (May 27, 2019): 276–80. http://dx.doi.org/10.1515/mammalia-2018-0008.

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Abstract The desert shrew Notiosorex crawfordi is the smallest mammal in the arid and semiarid areas of North America. It displays ecological adaptations that allow it to colonize environments inhospitable for other species in the Order Soricomorpha. Little is known about the natural history of this species; hence, this work reports the characteristics of foraging behavior, prey items, prey size and bite effectiveness on prey items of similar or larger size than these shrews. The behavior in captivity of two individuals of N. crawfordi captured in Baja California Sur was analyzed in glass terrariums, recording the locomotion, posture, food preferences, prey manipulation and bite effectiveness. Preference for prey items collected from the same transects/habitat as the shrews and differing in size and belonging to different groups of Arthropoda was evaluated, revealing a greater preference for scorpions, which were attacked within 1 min of being placed in the terrarium. Observations of foraging behavior of captive desert shrews show that prey items from the different arthropod groups and lizards become paralyzed at the first bite. The behavior displayed by the prey suggested the potential presence of toxins in the saliva of N. crawfordi.

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Li, Xiliang, Yong Ding, Yanting Yin, Tingting Yang, Zhiying Liu, Weibo Ren, JiangLi Zhang, Sarula, Yuanheng Li, and Xiangyang Hou. "Patterns of herders’ adaptation to changes in social–ecological systems across northern China’s grasslands over the past three decades." Rangeland Journal 39, no. 4 (2017): 317. http://dx.doi.org/10.1071/rj16070.

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Understanding the changes in herders’ adaptation to environmental change can provide insight into humans’ adaptive mechanisms to different social–ecological systems, and is also important for the optimal management of grasslands. However, the existing and emerging patterns of herders’ adaptation to changes in social–ecological systems across different types of grasslands are poorly understood. This paper presents a systematic participatory investigation that was conducted to comprehensively understand herders’ adaptation in this context over the past three decades. Three counties in Inner Mongolia grasslands were selected as the case study sites, located in meadow steppe, typical steppe and desert steppe respectively. Our results indicate that herders’ perceptions partly fit with the reality of the actual changes. The majority of herders attributed their pasture’s quality degradation to reduced precipitation rather than overgrazing, a contradictory perception to previous scientific observations (overgrazing > climate change). Moreover, herders’ behaviour in relation to herbage storage and livestock structure had dramatically changed in terms of spatial and temporal patterns in Inner Mongolia, which benefited herders in production efficiency. Lambing time of sheep and goats occurred earlier than it did several decades ago across the three grassland types. This was attributed to a rise in temperature, increasing marketisation and developing infrastructure. In addition, there became evident a transformation in the animal husbandry production cycle from a two-year to one-year cycle. Our results highlighted that the transformation of herders’ behavioural strategies resulted from variations in spatial and temporal patterns of climate change, pasture degradation, new policies and marketisation in pastoral areas. These strategies can be seen as key mechanisms in long-term adaptation to changes in social–ecological systems, which benefit herders’ efficiency in grassland management.

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Barak, Orly, Fritz Geiser, and Noga Kronfeld-Schor. "Flood-induced multiday torpor in golden spiny mice (Acomys russatus)." Australian Journal of Zoology 66, no. 6 (2018): 401. http://dx.doi.org/10.1071/zo19061.

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Mammalian and avian torpor is widely viewed as an adaptation for survival of cold winters. However, in recent years it has been established that torpor can also be expressed in summer and that the functions of torpor are manyfold, including survival of adverse environmental events such as fires, storms, heat waves and droughts. Here we provide the first evidence on (1) torpor induction via an accidental flooding event in mammals (in captivity) and (2) expression of multiday torpor by spiny mice, lasting >7 times as long as usually observed for this desert rodent. Our data suggest yet another function of mammalian torpor, as a response to flood, in addition to many other adverse environmental events, and not just in response to cold.

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Sandmeier, F. C., K. R. Horn, and C. R. Tracy. "Temperature-independent, seasonal fluctuations in immune function of the Mojave Desert Tortoise (Gopherus agassizii)." Canadian Journal of Zoology 94, no. 8 (August 2016): 583–90. http://dx.doi.org/10.1139/cjz-2016-0010.

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As long-lived reptiles, Mojave Desert Tortoises (Gopherus agassizii (Cooper, 1861)) are expected to make substantial energetic investments in immune defense. This species also has many adaptations to living in an arid environment characterized by seasonal extremes in temperature and resource availability. By housing G. agassizii at a controlled, constant ambient temperature, we quantified predominantly temperature-independent, seasonal fluctuations in innate immune function and circulating leukocytes in a reptile. We found a decrease in bacteriocidal activity of the blood plasma in winter, with reduced function lasting into the spring. Lymphocyte numbers were elevated in fall and winter, whereas eosinophil numbers increased in summer. Thus, properties of the immune system were up- or down-regulated in different directions across the seasons. We found a much higher level of variation of leukocyte profiles among individuals than has previously been reported for other chelonians. Heterophil:lymphocyte ratios (indicative of chronic glucocorticoid levels) were not associated with any measure of immune function, and thus glucocorticoid does not seem to mediate the observed seasonal changes. We propose a new hypothesis to explain seasonal changes in immune function, based on seasonal resource limitation in the Mojave Desert, including the availability of dietary protein, energy, and opportunities for thermal regulation.

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Akhtar, Saeed, Mousa Alkhalaf, Adnan A. Khan, and Turki M. Almubrad. "Ultrastructure Features and Three-Dimensional Transmission Electron Tomography of Dhub Lizard (Uromastyx Aegyptia) Cornea and Its Adaptation to a Desert Environment." Microscopy and Microanalysis 22, no. 4 (August 2016): 922–32. http://dx.doi.org/10.1017/s1431927616011466.

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AbstractWe report ultrastructural features and transmission electron tomography of the dhub lizard (Uromastyx aegyptia) cornea and its adaptation to hot and dry environments. Six corneas of dhub lizards were fixed in 2.5% glutaraldehyde and processed for electron microscopy and tomography. The ultrathin sections were observed with a JEOL 1400 transmission electron microscope. The cornea of the dhub lizard is very thin (~28–30 µm). The epithelium constitutes ~14% of the cornea, whereas the stroma constitutes 80% of the cornea. The middle stromal lamellae are significantly thicker than anterior and posterior stromal lamellae. Collagen fibril (CF) diameters in the anterior stroma are variable in size (25–75 nm). Proteoglycans (PGs) are very large in the middle and posterior stroma, whereas they are small in the anterior stroma. Three-dimensional electron tomography was carried out to understand the structure and arrangement of the PG and CFs. The presence of large PGs in the posterior and middle stroma might help the animal retain a large amount of water to protect it from dryness. The dhub corneal structure is equipped to adapt to the dry and hot desert environment.

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Wooden, K. M., and G. E. Walsberg. "Effect of wind and solar radiation on metabolic heat production in a small desert rodent, Spermophilus tereticaudus." Journal of Experimental Biology 203, no. 5 (March 1, 2000): 879–88. http://dx.doi.org/10.1242/jeb.203.5.879.

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To understand better how complex interactions between environmental variables affect the energy balance of small diurnal animals, we studied the effects of the absence and presence of 950 W m(−)(2) simulated solar radiation combined with wind speeds ranging from 0. 25 to 1.00 m s(−)(1) on the metabolic rate and body temperature of the round-tailed ground squirrel Spermophilus tereticaudus. As wind speed increased from 0.25 to 1.00 m s(−)(1), metabolic heat production increased by 0.94 W in the absence of solar radiation and by 0.98 W in the presence of 950 W m(−)(2) simulated solar radiation. Exposure to simulated solar radiation reduced metabolic heat production by 0.68 W at a wind speed of 0.25 m s(−)(1), by 0.64 W at 0.50 m s(−)(1) and by 0.64 W at 1.00 m s(−)(1). Body temperature was significantly affected by environmental conditions, ranging from 32. 5 degrees C at a wind speed of 1.0 m s(−)(1) and no irradiance to 35. 6 degrees C at a wind speed of 0.50 m s(−)(1) with 950 W m(−)(2)short-wave irradiance. In addition, several unusual findings resulted from this study. The coat of S. tereticaudus is very sparse, and the observed heat transfer of 5.68+/−0.37 W m(−)(2) degrees C(−)(1) (mean +/− s.e.m., N=11) is much higher than expected from either allometric equations or comparative studies with other rodents of similar mass. Solar heat gain was remarkably low, equalling only 10 % of intercepted radiation and suggesting a remarkably high regional thermal resistance at the tissue level. Animals remained normally active and alert at body temperatures as low as 32.5 degrees C. These findings suggest a unique combination of adaptations that allow S. tereticaudus to exploit a harsh desert environment.

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Lindquist, Evert E., and Miloslav Zacharda. "A new genus and species of Rhagidiidae (Acari: Prostigmata) from Chihuahuan Desert litter in New Mexico." Canadian Journal of Zoology 65, no. 9 (September 1, 1987): 2149–58. http://dx.doi.org/10.1139/z87-328.

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A new genus and species of rhagidiid mite, Arhagidia monothrix, is described and illustrated from specimens collected from the Jornada ecological research site of the Chihuahuan Desert in southern New Mexico. Uniquely derived morphological characteristics of this taxon include a reduced palpal chaetotaxy, an unpaired seta inserted on the naso, enlarged and nearly contiguous coxisternal plates I, absence of rhagidial depressions where solenidia are inserted on tarsi I and II, two pairs of setiferous tubercles dorsodistally on tarsus I, and an elongated body with short appendages. Some of these reflect adaptations to living in the soil. Eupathidial setae are distinguished and denoted from setiform setae on the femoral, genual, fibial, and tarsal segments of the legs of a rhagidiid mite for the first time.

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Ribak, G., T. Strod, D. Weihs, and Z. Arad. "Optimal descent angles for shallow-diving cormorants." Canadian Journal of Zoology 85, no. 4 (April 2007): 561–73. http://dx.doi.org/10.1139/z07-031.

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Air-breathing divers should attempt to maximize foraging efficiency under the constraint of limited oxygen availability. For diving water birds, high buoyancy (owing to the air in the plumage) and the associated change in buoyancy with diving depth impose further constraints on the adaptation to aquatic life. Diving birds are expected to descend as fast as possible to escape the higher buoyancy near the water surface, but in practice, shallow-diving cormorants (genus Phalacrocorax Brisson, 1760) are often observed descending the water column in relatively small angles with respect to the water surface. We derive a theoretical biomechanical model for the energetics of the descent phase of a dive of foot-propelled cormorants feeding on benthic prey at shallow depth. The model shows that visually guided benthic feeders benefit energetically from diving at small descent angles when optical conditions and bottom depth allow. The model also explains the high variation in descent angles observed in free-ranging birds, as well as the observed correlation between descent angle and bottom depth in cormorants.

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Macías-Duarte, Alberto, Angel B. Montoya, W. Grainger Hunt, Alberto Lafón-Terrazas, and Robert Tafanelli. "Reproduction, Prey, and Habitat of the Aplomado Falcon (Falco Femoralis) in Desert Grasslands of Chihuahua, Mexico." Auk 121, no. 4 (October 1, 2004): 1081–93. http://dx.doi.org/10.1093/auk/121.4.1081.

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Abstract A breeding population of Aplomado Falcons (Falco femoralis) remains in the desert grasslands of Chihuahua, Mexico, despite their extirpation in the nearby southwestern United States. We monitored falcon reproduction at 35 territories during 1996-2002, a period of severe drought in the region. To test the influence of prey abundance and vegetation on falcon reproduction, we surveyed avian prey abundance through plot counts in 1998-2002 and characterized vegetation at each plot. Aplomado Falcon productivity declined from 1.57 fledglings per occupied territory in 1997 to 0.63 in 2002 at the larger of two study areas, a trend consistent with cumulative effects of consecutive years of low rainfall. Reproduction in the smaller area remained low throughout the study. Both productivity and incubation start date were significantly associated with prey bird abundance. Summer rain most likely influenced falcon reproduction by affecting seed abundance and therefore abundance of granivorous prey birds the following winter and spring. Falcons nested in open grasslands with sparse woody vegetation, an adaptation likely related to higher prey vulnerability and fewer predators. However, important prey birds were positively correlated with woody-plant density, which suggests that proximity of shrublands increased nest-site suitability.

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Alhajeri, Bader H., Ondreia J. Hunt, and Scott J. Steppan. "Molecular systematics of gerbils and deomyines (Rodentia: Gerbillinae, Deomyinae) and a test of desert adaptation in the tympanic bulla." Journal of Zoological Systematics and Evolutionary Research 53, no. 4 (June 8, 2015): 312–30. http://dx.doi.org/10.1111/jzs.12102.

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Lessa, Andrea. "Rituais de sacrifício: a sobrevivência de uma antiga dimensão do corpo humano." História, Ciências, Saúde-Manguinhos 14, no. 3 (September 2007): 907–19. http://dx.doi.org/10.1590/s0104-59702007000300012.

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A força da tradição é capaz de preservar costumes que caminham na contramão da trajetória sociocultural das populações urbanas atuais. Costumes como os rituais de sacrifício, apesar de muitas vezes condenados pela sociedade e de terem sofrido um sincretismo adaptativo, ainda guardam elementos tradicionais, confirmando sua importância como mediadores entre os mundos natural e sobrenatural. Um bom exemplo são as lutas rituais Tinku, identificadas em amostras esqueléticas pré-colombianas provenientes do deserto de Atacama, Chile, e que ainda persistem entre grupos andinos, com uma abrangência temporal de pelo menos 1.200 anos. O objetivo principal dessa luta é provocar o sangramento e a morte de seus participantes, oferecidos à divindade Pachamama para propiciar a fertilidade da terra e dos animais. Os rituais de sacrifício, como símbolos de identidade social, nos ajudam a conhecer melhor o ethos de sociedades passadas e atuais.

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Alhajeri, Bader H., and Scott J. Steppan. "A phylogenetic test of adaptation to deserts and aridity in skull and dental morphology across rodents." Journal of Mammalogy 99, no. 5 (August 10, 2018): 1197–216. http://dx.doi.org/10.1093/jmammal/gyy099.

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Alary, V., S. Messad, A. Aboul-Naga, M. A. Osman, I. Daoud, P. Bonnet, X. Juanes, and J. F. Tourrand. "Livelihood strategies and the role of livestock in the processes of adaptation to drought in the Coastal Zone of Western Desert (Egypt)." Agricultural Systems 128 (June 2014): 44–54. http://dx.doi.org/10.1016/j.agsy.2014.03.008.

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Bockhorst, Tobias, and Uwe Homberg. "Interaction of compass sensing and object-motion detection in the locust central complex." Journal of Neurophysiology 118, no. 1 (July 1, 2017): 496–506. http://dx.doi.org/10.1152/jn.00927.2016.

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Goal-directed behavior is often complicated by unpredictable events, such as the appearance of a predator during directed locomotion. This situation requires adaptive responses like evasive maneuvers followed by subsequent reorientation and course correction. Here we study the possible neural underpinnings of such a situation in an insect, the desert locust. As in other insects, its sense of spatial orientation strongly relies on the central complex, a group of midline brain neuropils. The central complex houses sky compass cells that signal the polarization plane of skylight and thus indicate the animal’s steering direction relative to the sun. Most of these cells additionally respond to small moving objects that drive fast sensory-motor circuits for escape. Here we investigate how the presentation of a moving object influences activity of the neurons during compass signaling. Cells responded in one of two ways: in some neurons, responses to the moving object were simply added to the compass response that had adapted during continuous stimulation by stationary polarized light. By contrast, other neurons disadapted, i.e., regained their full compass response to polarized light, when a moving object was presented. We propose that the latter case could help to prepare for reorientation of the animal after escape. A neuronal network based on central-complex architecture can explain both responses by slight changes in the dynamics and amplitudes of adaptation to polarized light in CL columnar input neurons of the system. NEW & NOTEWORTHY Neurons of the central complex in several insects signal compass directions through sensitivity to the sky polarization pattern. In locusts, these neurons also respond to moving objects. We show here that during polarized-light presentation, responses to moving objects override their compass signaling or restore adapted inhibitory as well as excitatory compass responses. A network model is presented to explain the variations of these responses that likely serve to redirect flight or walking following evasive maneuvers.

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Journal articles on the topic 'Desert animals – Adaptation'

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