Artículos de revistas: "Island giants"

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Itescu, Yuval, Johannes Foufopoulos, Rachel Schwarz, Petros Lymberakis, Alex Slavenko, Ioanna-Aikaterini Gavriilidi, Shai Meiri y Panayiotis Pafilis. "The Island of Extremes: Giants and Dwarfs on a Small Remote Island". Russian Journal of Herpetology 28, n.º 4 (1 de septiembre de 2021): 225–30. http://dx.doi.org/10.30906/1026-2296-2021-28-4-225-230.

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Body size evolution on islands is widely studied and hotly debated. Gigantism and dwarfism are thought to evolve under strong natural selection, especially on small remote islands. We report a curious co-occurrence of both dwarf and giant lizards on the same small, remote island (Plakida): the largest Podarcis erhardii (Lacertidae) and smallest Mediodactylus kotschyi sensu lato; Gekkonidae — the two commonest insular reptiles in the Aegean Sea. The geckos of Plakida have a peculiar tail-waving behavior, documented here for the first time in this genus. We suspect that P. erhardii evolved large size to consume geckos and the geckos evolved a unique tail-waving behavior as a defensive mechanism.

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Brown, D. P., L. Basch, D. Barshis, Z. Forsman, D. Fenner y J. Goldberg. "American Samoa’s island of giants: massive Porites colonies at Ta’u island". Coral Reefs 28, n.º 3 (11 de abril de 2009): 735. http://dx.doi.org/10.1007/s00338-009-0494-8.

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Hennekam, Jesse J., Roger B. J. Benson, Victoria L. Herridge, Nathan Jeffery, Enric Torres-Roig, Josep Antoni Alcover y Philip G. Cox. "Morphological divergence in giant fossil dormice". Proceedings of the Royal Society B: Biological Sciences 287, n.º 1938 (4 de noviembre de 2020): 20202085. http://dx.doi.org/10.1098/rspb.2020.2085.

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Insular gigantism—evolutionary increases in body size from small-bodied mainland ancestors—is a conceptually significant, but poorly studied, evolutionary phenomenon. Gigantism is widespread on Mediterranean islands, particularly among fossil and extant dormice. These include an extant giant population of Eliomys quercinus on Formentera, the giant Balearic genus † Hypnomys and the exceptionally large † Leithia melitensis of Pleistocene Sicily. We quantified patterns of cranial and mandibular shape and their relationships to head size (allometry) among mainland and insular dormouse populations, asking to what extent the morphology of island giants is explained by allometry. We find that gigantism in dormice is not simply an extrapolation of the allometric trajectory of their mainland relatives. Instead, a large portion of their distinctive cranial and mandibular morphology resulted from the population- or species-specific evolutionary shape changes. Our findings suggest that body size increases in insular giant dormice were accompanied by the evolutionary divergence of feeding adaptations. This complements other evidence of ecological divergence in these taxa, which span predominantly faunivorous to herbivorous diets. Our findings suggest that insular gigantism involves context-dependent phenotypic modifications, underscoring the highly distinctive nature of island faunas.

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Agenbroad, Larry D. "Giants and pygmies: Mammoths of Santa Rosa Island, California (USA)". Quaternary International 255 (marzo de 2012): 2–8. http://dx.doi.org/10.1016/j.quaint.2011.03.044.

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Gazzini, L., S. Gazzini y V. Dallari. "The mystery of easter’s island giants and their acromegalyc facies". Journal of Endocrinological Investigation 44, n.º 10 (11 de febrero de 2021): 2325–26. http://dx.doi.org/10.1007/s40618-021-01521-8.

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Van Epps, Heather L. "Singapore's multibillion dollar gamble". Journal of Experimental Medicine 203, n.º 5 (15 de mayo de 2006): 1139–42. http://dx.doi.org/10.1084/jem.20060895.

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Biopolis, Singapore's futuristic research hub. How does a country one-fourth the size of Rhode Island with little history in biomedical science become one of the world's biomedical research giants? The answer: with a pile of money and a large dose of chutzpah. Since 2000, Singapore has dumped more than US$2 billion into developing a biomedical research industry—from scratch. Is the gamble paying off?

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7

Geist, Valerius. "On speciation in Ice Age mammals, with special reference to cervids and caprids". Canadian Journal of Zoology 65, n.º 5 (1 de mayo de 1987): 1067–84. http://dx.doi.org/10.1139/z87-171.

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Five types of species can be identified in large mammals. The evolution of three types, Ice Age giants, island dwarfs, and hybrids, can be explained, but not that of tropical food specialists and continental paedomorphs. Ice Age giants, which arose while colonizing latitudes (altitudes) with increasingly seasonal climates and productivity pulses, are characterized by ornate social organs, large bodies, and ecological plasticity. Colonizing landscapes with decreasing seasonality appears to conserve (or re-evolve) primitiveness, producing paedomorphs. Island dwarfs appear to be shaped by efficiency selection in the absence of predators. The explanation of mammalian Ice Age evolution hinges on the sensitivity of mammals to environmental factors, in particular nutrition. Extremes in food abundance generate extremes in phenotypes and selection regimes. Abundance is linked to colonization and selection for new social and ecological adaptations; scarcity is typical of settled areas and maintenance regimes. These select for efficiency in the procurement, processing, and use of food. Rapid speciation is predicted during colonization, followed by a gradual, continuous fine tuning of the ecology of the new form. Neither the punctuated nor the gradualistic model of speciation adequately explains evolution in large mammals. Early predictions of the "dispersal hypothesis" of mammalian evolution have now been tested for caprids. Results from cytogenetic, electrophorectic, and immunodiffusion studies support the dispersal hypotheses.

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Fernando, Edwino S., John Michael M. Galindon y Perry S. Ong. "Rafflesia consueloae (Rafflesiaceae), the smallest among giants; a new species from Luzon Island, Philippines". PhytoKeys 61 (25 de febrero de 2016): 37–46. http://dx.doi.org/10.3897/phytokeys.61.7295.

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Hosner, Peter A., Joseph A. Tobias, Edward L. Braun y Rebecca T. Kimball. "How do seemingly non-vagile clades accomplish trans-marine dispersal? Trait and dispersal evolution in the landfowl (Aves: Galliformes)". Proceedings of the Royal Society B: Biological Sciences 284, n.º 1854 (3 de mayo de 2017): 20170210. http://dx.doi.org/10.1098/rspb.2017.0210.

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Dispersal ability is a key factor in determining insular distributions and island community composition, yet non-vagile terrestrial organisms widely occur on oceanic islands. The landfowl (pheasants, partridges, grouse, turkeys, quails and relatives) are generally poor dispersers, but the Old World quail ( Coturnix ) are a notable exception. These birds evolved small body sizes and high-aspect-ratio wing shapes, and hence are capable of trans-continental migrations and trans-oceanic colonization. Two monotypic partridge genera, Margaroperdix of Madagascar and Anurophasis of alpine New Guinea, may represent additional examples of trans-marine dispersal in landfowl, but their body size and wing shape are typical of poorly dispersive continental species. Here, we estimate historical relationships of quail and their relatives using phylogenomics, and infer body size and wing shape evolution in relation to trans-marine dispersal events. Our results show that Margaroperdix and Anurophasis are nested within the Coturnix quail, and are each ‘island giants’ that independently evolved from dispersive, Coturnix -like ancestral populations that colonized and were subsequently isolated on Madagascar and New Guinea. This evolutionary cycle of gain and loss of dispersal ability, coupled with extinction of dispersive taxa, can result in the false appearance that non-vagile taxa somehow underwent rare oceanic dispersal.

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Shirdan, Leon. "ISLAND HARBOURS AND THEIR INFLUENCE ON ADJACENT SHORES". Coastal Engineering Proceedings 1, n.º 7 (29 de enero de 2011): 45. http://dx.doi.org/10.9753/icce.v7.45.

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The purpose of this paper is to put forward an alternative solution to the problem of reconstitution of existing ports, generally too shallow for the large tankers and ore carriers. Usually, the existing moles are extended to deep water fairways and approaches to berths, docks and basins, dredged and adapted to the draught of the new giants. This is connected with enormous expenses. Sometimes completely new port units, as for instance Europort, are built. The Island Harbours, with their seaward position, will reduce the length of the shipway to the berths and thus provide a speedier turn-out of vessels. The cost of erection and maintenance of such a harbour is in most cases lower than in that of a conventional solution, due to short breakwaters and limited quantities of primary and maintenance dredging operations. Different alternatives of island ports can be adapted in most sandy coasts over the world. The changes in coastal regime which may result from erecting an island harbour connected with the mainland by a bridge or a causeway can turn out profitable for general cargo ships, and even fisherboats, especially on the coasts where till now cutting the sea approaches through the shallows and bars was often unacceptable, due to the enormous expenses involved.

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Kirch, Patrick V. "Among stone giants: The life of Katherine Routledge and her remarkable expedition to Easter Island". Journal of the History of the Behavioral Sciences 42, n.º 2 (2006): 181–82. http://dx.doi.org/10.1002/jhbs.20142.

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Wozniak, Joan A. "Among Stone Giants: The Life of Katherine Routledge and Her Remarkable Expedition to Easter Island (review)". Asian Perspectives 44, n.º 2 (2005): 416–19. http://dx.doi.org/10.1353/asi.2005.0036.

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13

Martin-Silverstone, Elizabeth, Mark P. Witton, Victoria M. Arbour y Philip J. Currie. "A small azhdarchoid pterosaur from the latest Cretaceous, the age of flying giants". Royal Society Open Science 3, n.º 8 (agosto de 2016): 160333. http://dx.doi.org/10.1098/rsos.160333.

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Pterosaur fossils from the Campanian–Maastrichtian of North America have been reported from the continental interior, but few have been described from the west coast. The first pterosaur from the Campanian Northumberland Formation (Nanaimo Group) of Hornby Island, British Columbia, is represented here by a humerus, dorsal vertebrae (including three fused notarial vertebrae), and other fragments. The elements have features typical of Azhdarchoidea, an identification consistent with dominance of this group in the latest Cretaceous. The new material is significant for its size and ontogenetic stage: the humerus and vertebrae indicate a wingspan of ca 1.5 m, but histological sections and bone fusions indicate the individual was approaching maturity at time of death. Pterosaurs of this size are exceedingly rare in Upper Cretaceous strata, a phenomenon commonly attributed to smaller pterosaurs becoming extinct in the Late Cretaceous as part of a reduction in pterosaur diversity and disparity. The absence of small juveniles of large species—which must have existed—in the fossil record is evidence of a preservational bias against small pterosaurs in the Late Cretaceous, and caution should be applied to any interpretation of latest Cretaceous pterosaur diversity and success.

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Scheibling, RE y R. Black. "Persistence of giants: population dynamics of the limpet Scutellastra laticostata on rocky shores in Western Australia". Marine Ecology Progress Series 646 (30 de julio de 2020): 79–92. http://dx.doi.org/10.3354/meps13364.

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Population dynamics and life history traits of the ‘giant’ limpet Scutellastra laticostata on intertidal limestone platforms at Rottnest Island, Western Australia, were recorded by interannual (January/February) monitoring of limpet density and size structure, and relocation of marked individuals, at 3 locations over periods of 13-16 yr between 1993 and 2020. Limpet densities ranged from 4 to 9 ind. m-2 on wave-swept seaward margins of platforms at 2 locations and on a rocky notch at the landward margin of the platform at a third. Juvenile recruits (25-55 mm shell length) were present each year, usually at low densities (<1 m-2), but localized pulses of recruitment occurred in some years. Annual survival rates of marked limpets varied among sites and cohorts, ranging from 0.42 yr-1 at the notch to 0.79 and 0.87 yr-1 on the platforms. A mass mortality of limpets on the platforms occurred in 2003, likely mediated by thermal stress during daytime low tides, coincident with high air temperatures and calm seas. Juveniles grew rapidly to adult size within 2 yr. Asymptotic size (L∞, von Bertalanffy growth model) ranged from 89 to 97 mm, and maximum size from 100 to 113 mm, on platforms. Growth rate and maximum size were lower on the notch. Our empirical observations and simulation models suggest that these populations are relatively stable on a decadal time scale. The frequency and magnitude of recruitment pulses and high rate of adult survival provide considerable inertia, enabling persistence of these populations in the face of sporadic climatic extremes.

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Justine, Jean-Lou, Leigh Winsor, Delphine Gey, Pierre Gros y Jessica Thévenot. "Giant worms chez moi! Hammerhead flatworms (Platyhelminthes, Geoplanidae, Bipalium spp., Diversibipalium spp.) in metropolitan France and overseas French territories". PeerJ 6 (22 de mayo de 2018): e4672. http://dx.doi.org/10.7717/peerj.4672.

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Background Species of the genera Bipalium and Diversibipalium, or bipaliines, are giants among land planarians (family Geoplanidae), reaching length of 1 m; they are also easily distinguished from other land flatworms by the characteristic hammer shape of their head. Bipaliines, which have their origin in warm parts of Asia, are invasive species, now widespread worldwide. However, the scientific literature is very scarce about the widespread repartition of these species, and their invasion in European countries has not been studied. Methods In this paper, on the basis of a four year survey based on citizen science, which yielded observations from 1999 to 2017 and a total of 111 records, we provide information about the five species present in Metropolitan France and French overseas territories. We also investigated the molecular variability of cytochrome-oxidase 1 (COI) sequences of specimens. Results Three species are reported from Metropolitan France: Bipalium kewense, Diversibipalium multilineatum, and an unnamed Diversibipalium ‘black’ species. We also report the presence of B. kewense from overseas territories, such as French Polynesia (Oceania), French Guiana (South America), the Caribbean French islands of Martinique, Guadeloupe, Saint Martin and Saint Barthélemy, and Montserrat (Central America), and La Réunion island (off South-East Africa). For B. vagum, observations include French Guiana, Guadeloupe, Martinique, Saint Barthélemy, Saint Martin, Montserrat, La Réunion, and Florida (USA). A probable new species, Diversibipalium sp. ‘blue,’ is reported from Mayotte Island (off South–East Africa). B. kewense, B. vagum and D. multilineatum each showed 0% variability in their COI sequences, whatever their origin, suggesting that the specimens are clonal, and that sexual reproduction is probably absent. COI barcoding was efficient in identifying species, with differences over 10% between species; this suggests that barcoding can be used in the future for identifying these invasive species. In Metropolitan south–west France, a small area located in the Department of Pyrénées-Atlantiques was found to be a hot-spot of bipaliine biodiversity and abundance for more than 20 years, probably because of the local mild weather. Discussion The present findings strongly suggest that the species present in Metropolitan France and overseas territories should be considered invasive alien species. Our numerous records in the open in Metropolitan France raise questions: as scientists, we were amazed that these long and brightly coloured worms could escape the attention of scientists and authorities in a European developed country for such a long time; improved awareness about land planarians is certainly necessary.

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Sousa, M. E. M., B. M. L. Martins y M. E. B. Fernandes. "Meeting the giants: The need for local ecological knowledge (LEK) as a tool for the participative management of manatees on Marajó Island, Brazilian Amazonian coast". Ocean & Coastal Management 86 (diciembre de 2013): 53–60. http://dx.doi.org/10.1016/j.ocecoaman.2013.08.016.

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Gou, Qi, Hui Huang, Yuecheng Wang, Rong Zeng, Daiying Zhou, Xuemei Huang, Dongmei Chen, Tao Ma y Qingshan Liu. "Case report of a rare giant bone island in a vertebral body combined with hemangioma". Journal of International Medical Research 49, n.º 5 (mayo de 2021): 030006052110106. http://dx.doi.org/10.1177/03000605211010699.

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This case report describes a rare giant bone island combined with hemangioma diagnosed in a patient with osteolytic vertebral metastases. The bone island’s greatest diameter was 3.15 cm, and bone islands of this size are rare in the literature. This article aims to provide clinicians with information about the diagnosis and relevant literature of bone islands.

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Murty, C. V. R., Durgesh C. Rai, Sudhir K. Jain, Hemant B. Kaushik, Goutam Mondal y Suresh R. Dash. "Performance of Structures in the Andaman and Nicobar Islands (India) during the December 2004 Great Sumatra Earthquake and Indian Ocean Tsunami". Earthquake Spectra 22, n.º 3_suppl (junio de 2006): 321–54. http://dx.doi.org/10.1193/1.2206122.

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The damage sustained by buildings and structures in the Andaman and Nicobar islands area was due to earthquake shaking and/or giant tsunami waves. While damage on Little Andaman Island and all the Nicobar Islands was predominantly tsunami-related, damage on islands north of Little Andaman Island was primarily due to earthquake shaking even though tsunami waves and high tides were also a concern. In general, the building stock consists of a large number of traditional and non-engineered structures. Many traditional structures are made of wood, and they performed well under the intensity-VII earthquake shaking sustained along the islands. However, a number of new reinforced concrete (RC) structures suffered severe damage or even collapse. Also, extensive damage occurred to the coastal and harbor structures in the Andaman and Nicobar islands.

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CORSINI-FOKA, MARIA, GERASIMOS KONDYLATOS, IOANNA KATSOGIANNOU, KONSTANTINOS GRITZALIS y GIANNI INSACCO. "On the occurrence of Lethocerus patruelis (Stål, 1855) (Hemiptera: Heteroptera: Nepomorpha: Belostomatidae) in Rhodes (eastern Mediterranean Sea)". Journal of Insect Biodiversity 13, n.º 1 (3 de diciembre de 2019): 10–14. http://dx.doi.org/10.12976/jib/2019.13.1.3.

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The finding in 2017 of a female of Lethocerus patruelis, a species rarely collected in the Aegean Islands, is documented from Rhodes (Greece), more than 160 years after its first record in the same island. The general distribution of the giant water bug and its occurrence in the area are briefly discussed.Keywords: Belostomatidae, giant water bug, Lethocerus patruelis, Aegean Sea, Rhodes, Greece

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Gil-Delgado, J. A., J. González-Solís y A. Barbosa. "Populations of breeding birds in Byers Peninsula, Livingston Island, South Shetland Islands". Antarctic Science 25, n.º 2 (20 de marzo de 2013): 303–6. http://dx.doi.org/10.1017/s0954102012000752.

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AbstractData about breeding populations of birds in the Antarctica are rare and fragmented. Thus, information about the status of the breeding populations of Antarctic birds is crucial given the current scenario of climate change, which is particularly acute in Antarctica. This paper presents new information about the populations of the Antarctic tern Sterna vittata, the kelp gull Larus dominicanus, the southern giant petrel Macronectes giganteus, the Antarctic skua Catharacta antarctica lonnbergi, the chinstrap penguin Pygoscelis antarctica and the gentoo penguin Pygoscelis papua on Byers Peninsula (Livingston Island, South Shetland Islands). We used line transects counts to estimate both densities and numbers of nests of the different species. We estimate that there are 398.96 birds km-2 of southern giant petrels (2793 individuals), 62.4 birds km-2 of Antarctic tern (3746 individuals) and 269.1 birds km-2 of kelp gull (1884 individuals). Furthermore, we found 15 nests of Antarctic skua in 25 km2, from which we can estimate that 60–91 birds must breed on Byers Peninsula. We also censused two colonies of gentoo penguins (3000 and 1200 pairs) and 50 pairs of chinstrap. Compared to previous estimates, gentoo penguins seem to have increased whereas chinstrap penguin have decreased. Finally, the populations of Antarctic tern, southern giant petrel and kelp gull have stabilized or slightly increased.

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Ramalho, Ricardo S., Gisela Winckler, José Madeira, George R. Helffrich, Ana Hipólito, Rui Quartau, Katherine Adena y Joerg M. Schaefer. "Hazard potential of volcanic flank collapses raised by new megatsunami evidence". Science Advances 1, n.º 9 (octubre de 2015): e1500456. http://dx.doi.org/10.1126/sciadv.1500456.

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Large-scale gravitational flank collapses of steep volcanic islands are hypothetically capable of triggering megatsunamis with highly catastrophic effects. Yet, evidence for the generation and impact of collapse-triggered megatsunamis and their high run-ups remains scarce or is highly controversial. Therefore, doubts remain on whether island flank failures truly generate enough volume flux to trigger giant tsunamis, leading to diverging opinions concerning the real hazard potential of such collapses. We show that one of the most prominent oceanic volcanoes on Earth—Fogo, in the Cape Verde Islands—catastrophically collapsed and triggered a megatsunami with devastating effects ~73,000 years ago. Our deductions are based on the recent discovery and cosmogenic3He dating of tsunamigenic deposits found on nearby Santiago Island, which attest to the impact of this giant tsunami and document wave run-up heights exceeding 270 m. The evidence reported here implies that Fogo’s flank failure involved at least one fast and voluminous event that led to a giant tsunami, in contrast to what has been suggested before. Our observations therefore further demonstrate that flank collapses may indeed catastrophically happen and are capable of triggering tsunamis of enormous height and energy, adding to their hazard potential.

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Hernández, J. J., A. L. Medina y I. Izquierdo. "Bones of giant lacertids from a new site on El Hierro (Canary Islands)". Amphibia-Reptilia 10, n.º 1 (1989): 63–69. http://dx.doi.org/10.1163/156853889x00296.

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AbstractA new deposit of giant lacertids is described from a volcanic cave in the western part of El Hierro island. On the basis of an analysis of the 388 pieces found in this deposit, using both the literature and osteological material from Tenerife and El Hierro, it is concluded that three different species are represented: Gallotia goliath (Mertens), now extinct in the Canary Islands, Gallotia simonyi (Stein.) and Gallotia galloti caesaris (Lehrs). The two last species are still present on the island. The presence of G. goliath in this deposit represents the first record of this species in the island of El Hierro.

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Pfeiffer, Simone y Hans-Ulrich Peter. "Ecological studies toward the management of an Antarctic tourist landing site (Penguin Island, South Shetland Islands)". Polar Record 40, n.º 4 (octubre de 2004): 345–53. http://dx.doi.org/10.1017/s0032247404003845.

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Increasing tourism in the Antarctic Peninsula region concerns scientists, policy-makers, and tourist companies with its potential negative effects on wildlife. Site-specific ecological studies have been initiated to examine differences in population dynamics and distribution of animals as well as their behavioural and physiological reactions to humans. Penguin Island (southeast of King George Island, South Shetland Islands, Antarctica) is frequently visited by tourists due to its high species diversity and aesthetic value. In two seasons, the authors conducted a bird census and studied behaviour and heart-rate changes of southern giant petrels and skuas relating to tourist visits on Penguin Island. Management recommendations are given, based on the study results. The protection of southern giant petrels should be increased by having a minimum distance of 50 m for all visitors. The eastern, southern, and western parts of the island should not be visited and should serve as refuge areas. The wildlife experience for tourists can still be enjoyed by concentrating visits to the northern and central part of Penguin Island. Use of a specific path to localise impacts in a prescribed area is recommended.

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Greenspan, A. y Michael J. Klein. "Giant bone island". Skeletal Radiology 25, n.º 1 (17 de enero de 1996): 67–69. http://dx.doi.org/10.1007/s002560050034.

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Lavery, Tyrone H. "A reassessment of the type locality of the giant rat Solomys salamonis (Rodentia : Muridae) from the Solomon Islands". Australian Mammalogy 36, n.º 1 (2014): 99. http://dx.doi.org/10.1071/am13019.

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The Solomon Islands support a diverse and highly endemic rodent fauna. Most species are poorly known and rarely encountered. Solomys salamonis is one such endemic species known only from the holotype collected in 1881. The type locality for the species has been repeatedly confused in the literature, and this uncertainty has hampered attempts to evaluate the status of the species. I reassessed the type locality based on review of the published literature and records and archives of the Australian Museum, Sydney. My review indicates that the type locality is Ugi Island, not Florida Island as widely reported in the recent literature. A subsequent, preliminary survey on Ugi Island failed to confirm the presence of the species; however, the occurrence of some original forest on Ugi Island encourages further detailed surveys to determine whether S. salamonis is still extant.

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Muhidin, Rahmat. "TOPONIMI MARITIM KABUPATEN NATUNA PRTOPONIMI MARITIM KABUPATEN NATUNA PROVINSI KEPULAUAN RIAU (MARITIME TOPONYMY OF NATUNA REGION OF RIAU ISLANDS PROVINCE)OVINSI KEPULAUAN RIAU Maritime of Toponymy Natuna Regency Riau IslandsProvince". Metalingua: Jurnal Penelitian Bahasa 18, n.º 1 (30 de junio de 2020): 111. http://dx.doi.org/10.26499/metalingua.v18i1.474.

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This writing discusses the names of islands, straits, capes, rivers, estuaries,maritime, nautical, seas, beaches, and coasts in Natuna Region of Riau Islands Province and aims at describing its names. This maritime toponymic study uses descriptive method, literature study, and maritime toponymic survey data. The results showed that there are 154 islands in Natuna Region which 27 of them are inhabited and the rest (127 islands) are not. Those islands can be classified into two groups, namely (1) Bunguran Islands and Serasan Islands. Based on the local legend the name bunguran referred to the name of a tree called Bungur; (2) Senua Island was formed based on the story of Sarimah who was cursed to be a giant rock that kept getting bigger and formed an island called Senua.AbstrakKajian ini membahas nama-nama pulau, selat, tanjung, sungai, muara, maritim, bahari, laut, pantai, dan pesisir di Kabupaten Natuna, Provinsi Kepulauan Riau dan bertujuan untuk mendeskripsikan nama-namanya dan merupakan kajian toponimi maritim/letak geografis terkait kelautan di Kabupaten Natuna. Metode yang digunakan adalah metode deskriptif, studi literatur, dan data survei toponimi maritim. Hasil kajian menunjukkan bahwa di Kabupaten Natuna terdapat 154 pulau dengan 27 pulau berpenghuni dan sebagian besar pulau (127 buah) tidak berpenghuni.Pulau-pulau yang ada dapat dikelompokkan ke dalam 2 gugusan, yaitu (1) Pulau Bunguran dan Pulau Serasan. Penamaan Bunguran merujuk pada vegetasi tanaman pohon Bungur; (2) Pulau Senua merupakan pulau yang tercipta berdasar legenda rakyat Sarimah yang berubah menjadi batu yang membesar menjadi Pulau Senua.

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Turvey, Samuel T., Jennifer J. Crees, James Hansford, Timothy E. Jeffree, Nick Crumpton, Iwan Kurniawan, Erick Setiyabudi et al. "Quaternary vertebrate faunas from Sumba, Indonesia: implications for Wallacean biogeography and evolution". Proceedings of the Royal Society B: Biological Sciences 284, n.º 1861 (30 de agosto de 2017): 20171278. http://dx.doi.org/10.1098/rspb.2017.1278.

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Historical patterns of diversity, biogeography and faunal turnover remain poorly understood for Wallacea, the biologically and geologically complex island region between the Asian and Australian continental shelves. A distinctive Quaternary vertebrate fauna containing the small-bodied hominin Homo floresiensis , pygmy Stegodon proboscideans, varanids and giant murids has been described from Flores, but Quaternary faunas are poorly known from most other Lesser Sunda Islands. We report the discovery of extensive new fossil vertebrate collections from Pleistocene and Holocene deposits on Sumba, a large Wallacean island situated less than 50 km south of Flores. A fossil assemblage recovered from a Pleistocene deposit at Lewapaku in the interior highlands of Sumba, which may be close to 1 million years old, contains a series of skeletal elements of a very small Stegodon referable to S. sumbaensis , a tooth attributable to Varanus komodoensis , and fragmentary remains of unidentified giant murids. Holocene cave deposits at Mahaniwa dated to approximately 2000–3500 BP yielded extensive material of two new genera of endemic large-bodied murids, as well as fossils of an extinct frugivorous varanid. This new baseline for reconstructing Wallacean faunal histories reveals that Sumba's Quaternary vertebrate fauna, although phylogenetically distinctive, was comparable in diversity and composition to the Quaternary fauna of Flores, suggesting that similar assemblages may have characterized Quaternary terrestrial ecosystems on many or all of the larger Lesser Sunda Islands.

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Liu, Jun, Dan Cui, Hui Wang, Jiawei Chen, Helu Liu y Haibin Zhang. "Extensive cryptic diversity of giant clams (Cardiidae: Tridacninae) revealed by DNA-sequence-based species delimitation approaches with new data from Hainan Island, South China Sea". Journal of Molluscan Studies 86, n.º 1 (febrero de 2020): 56–63. http://dx.doi.org/10.1093/mollus/eyz033.

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Abstract Accurate species delimitation is important, especially for endangered species. As one of the most conspicuous bivalve taxa, giant clams are threatened throughout their geographic range. Many phylogeographic studies have revealed strong population structure among giant clams in the Indo-Pacific, suggesting cryptic diversity within these species. However, less attention has been paid to their identification and delimitation. In this study, we assembled a comprehensive dataset of mitochondrial cytochrome c oxidase subunit I (COI) sequences for Tridacna species, focusing on new sequences from Hainan Island in the South China Sea and previously published ones from Japan, Taiwan, Singapore, the Philippines, Indonesia, Australia, the Solomon Islands and the Red Sea. Three nominal species, Tridacna crocea, T. squamosa and T. noae, were recognized at Hainan Island on the basis of distance-based DNA barcoding, with mean interspecific K2P distances of 10.6–24.7% for seven Tridacna species (T. crocea, T. squamosa, T. noae, T. maxima, T. mbalavuana, T. derasa and T. gigas). The most abundant species, T. noae, represents the first record of this species from Hainan Island. Using a combination of phylogenetic and DNA-based species delimitation analyses (automatic barcode gap discovery, generalized mixed Yule coalescent and Bayesian Poisson tree processes), we found strong support for a total of 13 operational taxonomic units (OTUs) for the seven nominal Tridacna species. These results, coupled with the fact that each OTU occupies different regions in the Indo-Pacific, strongly suggest multiple cryptic species of giant clams. Our findings point to the need for taxonomic revisionary work on giant clams throughout the Indo-Pacific; such work will have important conservation implications.

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ANDRÉFOUËT, SERGE, SIMON VAN WYNSBERGE, LINA KABBADJ, COLETTE C. C. WABNITZ, CHRISTOPHE MENKES, THIERRY TAMATA, MICHEL PAHUATINI et al. "Adaptive management for the sustainable exploitation of lagoon resources in remote islands: lessons from a massive El Niño-induced giant clam bleaching event in the Tuamotu atolls (French Polynesia)". Environmental Conservation 45, n.º 1 (10 de abril de 2017): 30–40. http://dx.doi.org/10.1017/s0376892917000212.

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SUMMARYSmall-scale mariculture of high-value species for trade in remote islands can offer valuable alternative livelihoods to local communities. The endangered giant clam speciesTridacna maximais naturally abundant in some atolls in French Polynesia (FP) and has been the focus of commercial mariculture activities since 2012. Shortly after spat collectors became operational in two atoll lagoons, FP rose to become one of the main exporters of giant clams for the aquarium trade. However, this activity has been threatened recently by a mass clam-bleaching event triggered by the 2015–2016 El Niño. This study reviews the roles that international (Convention on International Trade in Endangered Species of Wild Fauna and Flora) and national regulatory frameworks play in the development of this activity in a small island context, and how they can indirectly promote better science and monitoring in order to inform adaptive management strategies. The links between the nine main groups of stakeholders show the necessary adaptation measures required to mitigate climate-driven mortalities. While this case study remains specific to giant clam farming in FP, general lessons are provided that could help in mitigating economic impacts from climate-related events on other islands.

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30

Andréfouët, Serge, Kim Friedman, Antoine Gilbert y Georges Remoissenet. "A comparison of two surveys of invertebrates at Pacific Ocean islands: the giant clam at Raivavae Island, Australes Archipelago, French Polynesia". ICES Journal of Marine Science 66, n.º 9 (22 de mayo de 2009): 1825–36. http://dx.doi.org/10.1093/icesjms/fsp148.

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Abstract Andréfouët, S., Friedman, K., Gilbert, A., and Remoissenet, G. 2009. A comparison of two surveys of invertebrates at Pacific Ocean islands: the giant clam at Raivavae Island, Australes Archipelago, French Polynesia. – ICES Journal of Marine Science, 66: 1825–1836. An assessment of invertebrate fisheries is currently taking place at several Pacific Ocean islands. The objectives are to obtain either detailed information on certain stocks at limited sites or to assess more broadly a variety of benthic resources across different islands. In French Polynesia, giant clam (Tridacna maxima) populations were surveyed by Service de la Pêche and Institut de Recherche pour le Développement (SPE/IRD). Sampling was optimized to determine stock abundance as a tool to enhance management of the clam fishery. Currently, the Secretariat of the Pacific Community (SPC) is investigating throughout the Pacific the status of invertebrate resources; a large-scale study not necessarily establishing a precise stock estimate for resources such as clams, but comparing resource status for several target species using coverage, density, and size measures. Raivavae Island (French Polynesia) was investigated by both programmes and offered an opportunity to verify whether the different sampling schedules provided consistent perspectives of the status of the T. maxima resource. The different strategies that SPE/IRD and SPC adopted resulted in no direct spatial overlap between the locations investigated: nevertheless, the ranges of densities and clam sizes recorded were generally consistent between surveys, and both programmes described similar spatial variation in clam presence at an island scale. SPE/IRD provided a detailed map of clam densities per habitat using a high-resolution satellite image, which yielded an estimated standing stock of 8.16 ± 0.91 million clams, representing a flesh biomass of 354 ± 41 t. SPC's study delivered coverage, density, and clam length, but no stock estimate. Unavailable from SPE/IRD, SPC also described the status of a variety of important invertebrate species targeted by fishers in the Pacific. Both programmes independently made similar fishery management recommendations. The relative merits and complementarities of the two approaches in the context of Pacific Ocean Island resource management are discussed.

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Nolte, Mark J., Peicheng Jing, Colin N. Dewey y Bret A. Payseur. "Giant Island Mice Exhibit Widespread Gene Expression Changes in Key Metabolic Organs". Genome Biology and Evolution 12, n.º 8 (12 de junio de 2020): 1277–301. http://dx.doi.org/10.1093/gbe/evaa118.

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Abstract Island populations repeatedly evolve extreme body sizes, but the genomic basis of this pattern remains largely unknown. To understand how organisms on islands evolve gigantism, we compared genome-wide patterns of gene expression in Gough Island mice, the largest wild house mice in the world, and mainland mice from the WSB/EiJ wild-derived inbred strain. We used RNA-seq to quantify differential gene expression in three key metabolic organs: gonadal adipose depot, hypothalamus, and liver. Between 4,000 and 8,800 genes were significantly differentially expressed across the evaluated organs, representing between 20% and 50% of detected transcripts, with 20% or more of differentially expressed transcripts in each organ exhibiting expression fold changes of at least 2×. A minimum of 73 candidate genes for extreme size evolution, including Irs1 and Lrp1, were identified by considering differential expression jointly with other data sets: 1) genomic positions of published quantitative trait loci for body weight and growth rate, 2) whole-genome sequencing of 16 wild-caught Gough Island mice that revealed fixed single-nucleotide differences between the strains, and 3) publicly available tissue-specific regulatory elements. Additionally, patterns of differential expression across three time points in the liver revealed that Arid5b potentially regulates hundreds of genes. Functional enrichment analyses pointed to cell cycling, mitochondrial function, signaling pathways, inflammatory response, and nutrient metabolism as potential causes of weight accumulation in Gough Island mice. Collectively, our results indicate that extensive gene regulatory evolution in metabolic organs accompanied the rapid evolution of gigantism during the short time house mice have inhabited Gough Island.

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32

CARRACEDO, J. C., S. DAY, H. GUILLOU, E. RODRÍGUEZ BADIOLA, J. A. CANAS y F. J. PÉREZ TORRADO. "Hotspot volcanism close to a passive continental margin: the Canary Islands". Geological Magazine 135, n.º 5 (septiembre de 1998): 591–604. http://dx.doi.org/10.1017/s0016756898001447.

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The Canarian Archipelago is a group of volcanic islands on a slow-moving oceanic plate, close to a continental margin. The origins of the archipelago are controversial: a hotspot or mantle plume, a zone of lithospheric deformation, a region of compressional block-faulting or a rupture propagating westwards from the active Atlas Mountains fold belt have been proposed by different authors. However, comparison of the Canarian Archipelago with the prototypical hotspot-related island group, the Hawaiian Archipelago, reveals that the differences between the two are not as great as had previously been supposed on the basis of older data. Quaternary igneous activity in the Canaries is concentrated at the western end of the archipelago, close to the present-day location of the inferred hotspot. This is the same relationship as seen in the Hawaiian and Cape Verde islands. The latter archipelago, associated with a well-defined but slow-moving mantle plume, shows anomalies in a plot of island age against distance which are comparable to those seen in the Canary Islands: these anomalies cannot therefore be used to argue against a hotspot origin for the Canaries. Individual islands in both archipelagoes are characterized by initial rapid growth (the ‘shield-building’ stages of activity), followed by a period of quiescence and deep erosion (erosion gap) which in turn is followed by a ‘post-erosional’ stage of activity. The absence of post-shield stage subsidence in the Canaries is in marked contrast with the major subsidence experienced by the Hawaiian Islands, but is comparable with the lack of subsidence evident in other island groups at slow-moving hotspots, such as the Cape Verdes. Comparison of the structure and structural evolution of the Canary Islands with other oceanic islands such as Hawaii and Réunion reveals many similarities. These include the development of triple (‘Mercedes Star’) rift zones and the occurrence of giant lateral collapses on the flanks of these rift zones. The apparent absence of these features in the post-erosional islands may in part be a result of their greater age and deeper erosion, which has removed much of the evidence for their early volcanic architecture. We conclude that the many similarities between the Canary Islands and island groups whose hotspot origins are undisputed show that the Canaries have been produced in the same way.

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OLIVER, PAUL M., JONATHAN R. CLEGG, ROBERT N. FISHER, STEPHEN J. RICHARDS, PETER N. TAYLOR y MERLIJN M. T. JOCQUE. "A new biogeographically disjunct giant gecko (Gehyra: Gekkonidae: Reptilia) from the East Melanesian Islands". Zootaxa 4208, n.º 1 (14 de diciembre de 2016): 61. http://dx.doi.org/10.11646/zootaxa.4208.1.3.

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The East Melanesian Islands have been a focal area for research into island biogeography and community ecology. However, previously undescribed and biogeographically significant new species endemic to this region continue to be discovered. Here we describe a phylogenetically distinct (~20% divergence at the mitochondrial ND2 gene) and biogeographically disjunct new species of gecko in the genus Gehyra, from the Admiralty and St Matthias Islands. Gehyra rohan sp. nov. can be distinguished from all congeners by the combination of its very large size, ring of bright orange scales around the eye, moderate degree of lateral folding on the limbs and body, and aspects of head, body and tail scalation. Molecular data indicate mid to late Miocene divergence of the new species from nearest relatives occurring nearly 2000 kilometres away in Vanuatu and Fiji. Large Gehyra have not been recorded on the intervening large islands of the Bismark Archipelago (New Britain and New Ireland) and the Solomon Islands, suggesting this dispersal pre-dated the current configuration of these islands, extinction in intervening regions, or potentially elements of both. Conversely, low genetic divergence between disjunct samples on Manus and Mussau implies recent overseas dispersal via either natural or anthropogenic means.

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Gittins, Oliver, Llorenç Grau-Roma, Rosa Valle, Francesc Xavier Abad, Miquel Nofrarías, Peter G. Ryan, Jacob González-Solís y Natàlia Majó. "Serological and molecular surveys of influenza A viruses in Antarctic and sub-Antarctic wild birds". Antarctic Science 32, n.º 1 (3 de diciembre de 2019): 15–20. http://dx.doi.org/10.1017/s0954102019000464.

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AbstractTo evaluate how avian influenza virus (AIV) circulates among the avifauna of the Antarctic and sub-Antarctic islands, we surveyed 14 species of birds from Marion, Livingston and Gough islands. A competitive enzyme-linked immunosorbent assay was carried out on the sera of 147 birds. Quantitative reverse transcription polymerase chain reaction was used to detect the AIV genome from 113 oropharyngeal and 122 cloacal swabs from these birds. The overall seroprevalence to AIV infection was 4.8%, with the only positive results coming from brown skuas (Catharacta antarctica) (4 out of 18, 22%) and southern giant petrels (Macronectes giganteus) (3 out of 24, 13%). Avian influenza virus antibodies were detected in birds sampled from Marion and Gough islands, with a higher seroprevalence on Marion Island (P = 0.014) and a risk ratio of 11.29 (95% confidence interval: 1.40–91.28) compared to Gough Island. The AIV genome was not detected in any of the birds sampled. These results confirm that AIV strains are uncommon among Antarctic and sub-Antarctic predatory seabirds, but they may suggest that scavenging seabirds are the main avian reservoirs and spreaders of this virus in the Southern Ocean. Further studies are necessary to determine the precise role of these species in the epidemiology of AIV.

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35

Budd, Grahame M. "Australian exploration of Heard Island, 1947–1971". Polar Record 43, n.º 2 (28 de marzo de 2007): 97–123. http://dx.doi.org/10.1017/s0032247407006080.

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In 1947 knowledge of Heard Island was confined to a rough mapping compiled by nineteenth-century sealers, and the results of four scientific expeditions that had briefly investigated the Atlas Cove area. Exploration continued in two distinct periods between 1947 and 1971. In the first period the Australian National Antarctic Research Expeditions (ANARE) built a scientific station at Atlas Cove in 1947, and occupied it continuously until 1955 as an ‘A Class’ meteorological station, a seismic and magnetic observatory, and a base for other scientific studies and for exploration of the island. In the second period four summer expeditions and one wintering expedition worked on the island between 1963 and 1971. The summer expeditions were an ANARE expedition in 1963, an Australian private expedition (The South Indian Ocean Expedition to Heard Island) in 1965, and ANARE expeditions in 1969 and 1971 associated with United States and French expeditions. A United States expedition wintered in 1969. There were no further expeditions until 1980. The years 1947–1971 saw many achievements. Expedition members recorded seven years of synoptic meteorological observations and four years of seismic and magnetic observations. They developed empirical techniques of work, travel, and survival that shaped the collective character of ANARE and were later applied in Antarctica. Despite difficult terrain and consistently bad weather, and the accidental deaths of two men in 1952, unsupported field parties of two or three men travelling on foot explored and mapped in detail the heavily glaciated island, and documented its topography, geology, glaciology and biology. They made three overland circuits of the island, the first ascent of Big Ben (2745 m), and the first recorded landing on the nearby McDonald Islands. Expedition members bred and trained dog teams for later use in Antarctica. They reported the commencement and subsequent progress of massive glacier retreat caused by regional warming, and of the island's colonisation by king penguins (Aptenodytes patagonicus) and antarctic fur seals (Arctocephalus gazella). They also reported measurements of glacier flow and thickness, the palaeomagnetism of Heard Island rocks, behavioural and population studies of southern giant petrels (Macronectes giganteus) and other birds, studies of southern elephant seals (Mirounga leonina) and leopard seals (Hydrurga leptonyx), and the cold stress and acclimatisation experienced by humans working in the island's wet-cold climate. In addition, Heard Island served as a testing ground for men, equipment, scientific programmes, huskies, general administration, and logistics, without which Mawson station could not have been established as successfully as it was in 1954. The American wintering expedition and the French summer expedition contributed to major international geodetic and geophysical investigations. In sum, the expeditions between 1947 and 1971 added much to our knowledge of Heard Island, and they laid down a solid foundation for the work of later expeditions.

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Barbeck, Mike, Jonas Lorenz, Alica Kubesch, Nicole Böhm, Patrick Booms, Joseph Choukroun, Robert Sader, Charles James Kirkpatrick y Shahram Ghanaati. "Porcine Dermis-Derived Collagen Membranes Induce Implantation Bed Vascularization Via Multinucleated Giant Cells: A Physiological Reaction?" Journal of Oral Implantology 41, n.º 6 (1 de diciembre de 2015): e238-e251. http://dx.doi.org/10.1563/aaid-joi-d-14-00274.

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In this study, the tissue reactions to 2 new porcine dermis-derived collagen membranes of different thickness were analyzed. The thicker material (Mucoderm) contained sporadically preexisting vessel skeletons and fatty islands. The thinner membrane (Collprotect) had a bilayered structure (porous and occlusive side) without any preexisting structures. These materials were implanted subcutaneously in mice to analyze the tissue reactions and potential transmembranous vascularization. Histological and histomorphometrical methodologies were performed at 4 time points (3, 10, 15, and 30 days). Both materials permitted stepwise connective tissue ingrowth into their central regions. In the Mucoderm matrix, newly built microvessels were found within the preexisting vessel and fatty island skeletons after 30 days. This vascularization was independent of the inflammation-related vascularization on both material surfaces. The Collprotect membrane underwent material disintegration by connective tissue strands in combination with vessels and multinucleated giant cells. The histomorphometric analyses revealed that the thickness of Mucoderm did not decrease significantly, while an initial significant decrease of membrane thickness in the case of Collprotect was found at day 15. The present results demonstrate that the 2 analyzed collagen membranes underwent a multinucleated giant cell-associated vascularization. Neither of the materials underwent transmembraneous vascularization. The microvessels were found within the preexisting vessel and fatty island skeletons. Additional long-term studies and clinical studies are necessary to determine how the observed foreign body giant cells affect tissue regeneration.

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Salomon, Marc y Jean-François Voisin. "Ecogeographical variation in the Southern Giant Petrel (Macronectes giganteus)". Canadian Journal of Zoology 88, n.º 2 (febrero de 2010): 195–203. http://dx.doi.org/10.1139/z09-134.

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The Southern Giant Petrel ( Macronectes giganteus (Gmelin, 1789); Aves, Procellariiformes), ranging from New Zealand to the Graham Peninsula and Patagonia and also from coastal Antarctica to Gough Island, displays significant geographic variation throughout its range. Six breeding provinces were identified, which show significant interpopulational variation. The formerly proposed subspecies Macronectes giganteus giganteus and Macronectes giganteus solanderi were confirmed. Macronectes giganteus solanderi has smaller homologuous parts than M. g. giganteus. Two of the provinces belong to the subspecies M. g. solanderi. Females are smaller and have shorter bills than males. In M. g. giganteus, outer appendages are longer in the sub-Antarctic than in the Antarctic, which is consistent with Allen’s rule. Moreover, an east-to-west cline shows a gradual decrease in body size. Within M. g. solanderi, the Chubut River Estuary (Argentina) and the Falkland Islands form the southern province, and Gough Island the northern province. The birds have shallower bills in Argentina than in the Falklands or Gough, but tarsi are longest in Gough. Macronectes giganteus giganteus is morphologically polymorphic but taxonomically stable, whereas M. g. solanderi, which is biometrically less variable, could undergo taxonomical differentiation. This paper gives arguments for further morphometric and genetic studies on the taxon.

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Brien, Earl W., Joseph M. Mirra, Lisa Latanza, Alexander Fedenko y James Luck. "Giant bone island of femur". Skeletal Radiology 24, n.º 7 (octubre de 1995): 546–50. http://dx.doi.org/10.1007/bf00202158.

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Márquez, Cruz, David A. Wiedenfeld, Sandra Landázuri y Juan Chávez. "Human-caused and natural mortality of giant tortoises in the Galapagos Islands during 1995-2004". Oryx 41, n.º 3 (julio de 2007): 337–42. http://dx.doi.org/10.1017/s0030605307000211.

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AbstractAlthough the killing of giant tortoises in the Galapagos Islands has been prohibited since 1933, poaching of tortoises still occurs. Personnel of the Galapagos National Park Service and the Charles Darwin Research Station regularly survey populations of tortoises throughout the archipelago and report all dead tortoises found. For the 10-year period 1995–2004 the field personnel reported evidence of 190 giant tortoises killed, primarily on the southern portion of Isabela Island. For the first 6 years the number of tortoises found killed was <15 per year, but since 2001 the number killed has increased dramatically, with 49 tortoises poached in 2004. During the same 10 years the number of tortoises found dead from natural causes was 131. Many of these deaths can be attributed to events associated with the 1997–1998 El Niño or with outbreaks of disease on Santa Cruz Island in 1996 and 1999. The results indicate that poaching exceeds natural mortality, and is a significant factor affecting these long-lived and slow-reproducing animals. Environmental education efforts in the human population of southern Isabela appear to have had little effect. Because tortoise poaching takes place at a small number of sites, effective enforcement at those sites could reduce killing of tortoises.

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Rijsdijk, Kenneth F., Jens Zinke, Perry G. B. de Louw, Julian P. Hume, Hans (J ). van der Plicht, Henry Hooghiemstra, Hanneke J. M. Meijer et al. "Mid-Holocene (4200 kyr BP) mass mortalities in Mauritius (Mascarenes): Insular vertebrates resilient to climatic extremes but vulnerable to human impact". Holocene 21, n.º 8 (18 de julio de 2011): 1179–94. http://dx.doi.org/10.1177/0959683611405236.

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In the light of the currently increasing drought frequency and water scarcity on oceanic islands, it is crucial for the conservation of threatened insular vertebrates to assess how they will be affected. A 4000 yr old fossil assemblage in the Mare Aux Songes (MAS), southwest Mauritius, Mascarene Islands, contains bones of 100 000+ individual vertebrates, dominated by two species of giant tortoises Cylindraspis triserrata and C. inepta, the dodo Raphus cucullatus, and 20 other vertebrate species ( Rijsdijk, Hume, Bunnik, Florens, Baider, Shapiro et al. (2009) Mid-Holocene vertebrate bone Concentration-Lagerstätte on oceanic island Mauritius provides a window into the ecosystem of the dodo ( Raphus cucullatus). Quaternary Science Reviews 28: 14–24). Nine radiocarbon dates of bones statistically overlap and suggest mass mortality occurred between 4235 and 4100 cal. yr BP. The mortality period coincides with a widely recognized megadrought event. Our multidisciplinary investigations combining geological, paleontological and hydrological evidence suggests the lake was located in a dry coastal setting and had desiccated during this period. Oxygen isotope data from a Uranium-series dated stalagmite from Rodrigues, an island 560 km east of Mauritius, supports this scenario by showing frequently alternating dry and wet periods lasting for decades between 4122 and 2260 cal. yr BP. An extreme drought resulted in falling water-tables at MAS and elsewhere on the island, perhaps deprived these insular vertebrates of fresh water, which led to natural mass mortalities and possibly to extirpations. In spite of these events, all insular species survived until at least the seventeenth century, confirming their resistance to climatic extremes. Despite this, the generally exponential increase of combined human impacts on islands including loss of geodiversity, habitats, and stocks of fresh water, there will be less environmental safe-haven options for insular endemic and native vertebrates during future megadrought conditions; and therefore will be more prone to extinction.

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Sota, Teiji, Michio Hori, Clarke Scholtz, Gayane Karagyan, Hong-Bin Liang, Hiroshi Ikeda y Yasuoki Takami. "The origin of the giant ground beetle Aplothorax burchelli on St Helena Island". Biological Journal of the Linnean Society 131, n.º 1 (1 de agosto de 2020): 50–60. http://dx.doi.org/10.1093/biolinnean/blaa093.

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Abstract Some highly isolated oceanic islands harbour endemic ground beetles that have lost the ability to fly. Here, we investigated the origin of the possibly extinct flightless giant ground beetle Aplothorax burchelli on St Helena Island in the South Atlantic. Aplothorax burchelli was initially considered to be a member of the subtribe Calosomina (=genus Calosoma) of the subfamily Carabinae (Coleoptera: Carabidae) closely related to the genus Ctenosta (=Calosoma subgenus Ctenosta), but this proposition was questioned due to its unique external and genital morphology. We conducted a phylogenetic analysis of mitogenome sequences using historical specimens of A. burchelli and samples of representative species of Carabinae. Our analysis of 13 protein-coding gene sequences revealed that A. burchelli is definitely a member of Calosomina, most closely related to a species of Ctenosta. Further analysis using NADH dehydrogenase subunit 5 gene sequences from most groups in Calosomina showed that A. burchelli formed a monophyletic group with Ctenosta species from Africa and Madagascar. Our results suggest that the ancestor of A. burchelli, which had the ability to fly, colonized St Helena from Africa after the emergence of the island 14 Mya, and has since undergone evolutionary changes in conjunction with loss of flight.

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Lavery, Tyrone H., Masaafi Alabai, Tommy Esau, Simon Fuiberi, Di'ifaka Furina, Rebecca N. Johnson, Esau Kekeubata, David MacLaren, Jackson Waneagea y Tim F. Flannery. "Integrating traditional knowledge, science and conservation in the search for undescribed mammals on Malaita, Solomon Islands". Pacific Conservation Biology 26, n.º 4 (2020): 404. http://dx.doi.org/10.1071/pc19037.

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Basic knowledge of species diversity and distributions underpins the study of island biogeography and is fundamental for conservation planning. In Solomon Islands, new mammals continue to be described and several lineages are yet to be documented from large islands where, presumably, they should occur. On Malaita and Makira, no giant rats (Solomys or Uromys), or monkey-faced bats (Pteralopex) have been documented by scientists, but traditional knowledge suggests they exist. In East Kwaio, Malaita, we combined traditional knowledge and scientific methods to survey mammals and search for these taxa. Camera traps, mist nets, spotlight surveys, echolocation call recorders, rat traps and active searches were used to produce an inventory of the island’s mammals. No Solomys, Uromys or Pteralopex were captured. However, detailed accounts suggest that giant rats and monkey-faced bats were present as recently as 1996 and 2002 respectively. Moreover, we consider the presence of gnawed Canarium nuts an indicator that giant rats still persist. The human population of Malaita is dense, hunting pressure appears high, feral cats are common, and logging is rapidly reducing primary forests. A notable feature of this work has been the commitment towards collaboration and upskilling landowners in mammal survey techniques. This collaboration has helped fuel a growing conservation movement on Malaita and led to the designation of three large conservation areas. Gathering evidence for the existence of undescribed mammals on Malaita is paramount for reducing further extinctions in Melanesia. Continued support for skilled community members in East Kwaio will be key to collecting this evidence.

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Arbi, Ucu Yanu. "KEPADATAN DAN KONDISI HABITAT KERANG KIMA (CARDIIDAE: TRIDACNINAE) DI BEBERAPA LOKASI DI PERAIRAN SULAWESI UTARA". BAWAL Widya Riset Perikanan Tangkap 3, n.º 2 (7 de febrero de 2017): 139. http://dx.doi.org/10.15578/bawal.3.2.2010.139-148.

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Kima merupakan salah satu jenis kerang laut yang telah dieksploitasi oleh nelayan Sulawesi Utara dalam skala besar karena memiliki nilai ekonomis yang tinggi. Penelitian ini bertujuan untuk mengetahui kepadatan dan kondisi habitat kerang kima di perairan Sulawesi Utara pada tahun 2007-2009. Daerah penelitian ini meliputi perairan Bitung, Pulau Lembeh, Taman Nasional Bunaken, Likupang, Pulau Talise, Kepulauan Sangihe, dan Kepulauan Talaud. Pengambilan data dilakukandengan metode rapid reef resources inventory dan metode kuadrat transek garis. Ditemukan 1.064 individu kima yang terdiri atas tujuh jenis, yaitu Tridacna crocea, Tridacna squamosa, Tridacna maxima, Tridacna derasa, Tridacna gigas, Hippopus hippopus, dan Hippopus porcelanus. Kepadatan kimasecara keseluruhan di lokasi penelitian rata-rata 0,53 ind./m2. Kepadatan tertinggi adalah jenis Tridacna crocea (rata-rata 0,32 ind./m2), sedangkan terendah adalah jenis Tridacna gigas, Tridacna derasa, dan Hippopus porcelanus (0,01 ind./m2). Giant clam is one of the sea shells that have been exploited by the fisherman of North Sulawesi, a large scale because it has a high economic value. This study aims to determine the distribution and density of giant clams in North Sulawesi waters in 2007-2009. Research conducted in the waters of Bitung, Pulau Lembeh, Bunaken National Park, Likupang, Talise Island, Sangihe Islands, and Talaud Islands. Data retrieval is done by the rapid reef resources inventory method and the quadrat line transect method. 1.064 individual of giant clams was found consisting of seven species, there are Tridacna crocea, Tridacna squamosa, Tridacna maxima, Tridacna derasa, Tridacna gigas, Hippopus hippopus and Hippopus porcelanus. Density of giant clams density is 0,53 ind./m2. The highest density of individuals is Tridacna crocea (0,32 ind./m2), while the lowest is Tridacna gigas, Tridacna derasa and Hippopus porcelanus (0.01 ind./m2).

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Aguilera, Washington Tapia, Jeffreys Málaga y James P. Gibbs. "Giant tortoises hatch on Galapagos island". Nature 517, n.º 7534 (enero de 2015): 271. http://dx.doi.org/10.1038/517271a.

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Ehara, Shigeru, Susan V. Kattapuram y Andrew E. Rosenberg. "Giant bone island computed tomography findings". Clinical Imaging 13, n.º 3 (septiembre de 1989): 231–33. http://dx.doi.org/10.1016/0899-7071(89)90154-x.

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Kehlmaier, Christian, Axel Barlow, Alexander K. Hastings, Melita Vamberger, Johanna L. A. Paijmans, David W. Steadman, Nancy A. Albury, Richard Franz, Michael Hofreiter y Uwe Fritz. "Tropical ancient DNA reveals relationships of the extinct Bahamian giant tortoise Chelonoidis alburyorum". Proceedings of the Royal Society B: Biological Sciences 284, n.º 1846 (11 de enero de 2017): 20162235. http://dx.doi.org/10.1098/rspb.2016.2235.

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Ancient DNA of extinct species from the Pleistocene and Holocene has provided valuable evolutionary insights. However, these are largely restricted to mammals and high latitudes because DNA preservation in warm climates is typically poor. In the tropics and subtropics, non-avian reptiles constitute a significant part of the fauna and little is known about the genetics of the many extinct reptiles from tropical islands. We have reconstructed the near-complete mitochondrial genome of an extinct giant tortoise from the Bahamas ( Chelonoidis alburyorum ) using an approximately 1 000-year-old humerus from a water-filled sinkhole (blue hole) on Great Abaco Island. Phylogenetic and molecular clock analyses place this extinct species as closely related to Galápagos ( C. niger complex) and Chaco tortoises ( C. chilensis ), and provide evidence for repeated overseas dispersal in this tortoise group. The ancestors of extant Chelonoidis species arrived in South America from Africa only after the opening of the Atlantic Ocean and dispersed from there to the Caribbean and the Galápagos Islands. Our results also suggest that the anoxic, thermally buffered environment of blue holes may enhance DNA preservation, and thus are opening a window for better understanding evolution and population history of extinct tropical species, which would likely still exist without human impact.

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DAY, S. J., J. C. CARRACEDO y H. GUILLOU. "Age and geometry of an aborted rift flank collapse: the San Andres fault system, El Hierro, Canary Islands". Geological Magazine 134, n.º 4 (julio de 1997): 523–37. http://dx.doi.org/10.1017/s0016756897007243.

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The catastrophic slope failures and landslides that occur in the final stages of lateral collapses of volcanoes destroy much of the evidence for precursory deformation and the early stages of the collapses concerned. Aborted or incomplete collapse structures, although rare, are rich sources of information on these stages of development of catastrophic collapses. The San Andres fault system, on the volcanic island of El Hierro, is a relatively young (between about 545 and about 261–176 ka old) but inactive lateral collapse structure. It appears to represent an aborted giant landslide. It is developed along the flank of a steep-sided volcanic rift zone, and is bounded by a discrete strike-slip fault zone at the up-rift end, closest to the centre of the island. This geometry differs markedly from that of collapse structures on stratovolcanoes but bears some similarities to that of active fault systems on Hawaii. Although the fault system has undergone little erosion, cataclasites which formed close to the palaeosurface are well exposed. These cataclasites are amongst the first fault rocks to be described from volcano lateral collapse structures and include the only pseudotachylytes to have been identified in such structures to date. Their development at unusually shallow depths is attributed to large movements on the fault in a single event, the inferred aborted landslide, and a lack of pressurized pore water. The absence of pressurized fluids in the slumping block may have caused the San Andres fault system to cease moving, rather than develop into a giant volcanic landslide. The recognition that the San Andres fault system is inactive greatly reduces the estimated volcanic hazard associated with El Hierro. However, the lack of evidence for precursory deformation prior to the aborted landslide event is disturbing as it implies that giant lateral collapses can occur on steep-sided oceanic islands with little warning.

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Dunn, M. J., J. A. Jackson, S. Adlard y R. A. Phillips. "Population size and trends of southern giant petrels (Macronectes giganteus) nesting at Signy Island, South Orkney Islands". Polar Biology 39, n.º 7 (10 de diciembre de 2015): 1309–17. http://dx.doi.org/10.1007/s00300-015-1855-0.

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Palacios-García, Sergio, Penélope Cruzado-Caballero, R. Casillas y Carolina Castillo Ruiz. "Quaternary biodiversity of the giant fossil endemic lizards from the island of El Hierro (Canary Islands, Spain)". Quaternary Science Reviews 262 (junio de 2021): 106961. http://dx.doi.org/10.1016/j.quascirev.2021.106961.

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Simons, Elwyn L., David A. Burney, Prithijit S. Chatrath, Laurie R. Godfrey, William L. Jungers y Berthe Rakotosamimanana. "AMS 14C Dates for Extinct Lemurs from Caves in the Ankarana Massif, Northern Madagascar". Quaternary Research 43, n.º 2 (marzo de 1995): 249–54. http://dx.doi.org/10.1006/qres.1995.1025.

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AbstractAn extensive late Quaternary fauna, including many extinct giant lemurs, has been collected recently in a 110+-km system of caves in the Ankarana Massif of northern Madagascar. AMS 14C dates for the acid-insoluble (collagen/gelatin) fraction of bones of the giant lemur Megaladapis (26,150 ± 400 and 12,760 ± 70 yr B.P.) confirm its presence in the area during the late Pleistocene and provide the first Pleistocene 14 C ages from bones of the extinct megafauna of the island. The first date from bones of the recently described extinct Babakotia radofilai (4400 ± 60 yr B.P.) shows that it was present in northern Madagascar in mid-Holocene times. A comparatively recent age of 1020 ± 50 yr B.P. for the extinct Archaeolemur indicates survival of this genus for at least a millennium after the first direct evidence for humans in Madagascar. This suggests that the island's "extinction window" may have represented a longer time span than would have been expected under the Blitzkrieg model of late Quaternary extinctions. A mid-Holocene age (4560 ± 70 yr B.P.) for a bone sample of the small extant lemur Hapalemur simus indicates that the disappearance of this now-restricted species from the Ankarana occurred after this date. New data from the Ankarana and other sites on the island add to the consensus that major biotic changes occurred on Madagascar in the late Holocene.

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