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Balkenhol N.,Leibniz Institute for Zoo and Wildlife Research | Landguth E.L.,University of Montana
Molecular Ecology | Year: 2011

With the emergence of landscape genetics, the basic assumptions and predictions of classical population genetic theories are being re-evaluated to account for more complex spatial and temporal dynamics. Within the last decade, there has been an exponential increase in such landscape genetic studies (Holderegger & Wagner 2006; Storfer 2010), and both methodology and underlying concepts of the field are under rapid and constant development. A number of major innovations and a high level of originality are required to fully merge existing population genetic theory with landscape ecology and to develop novel statistical approaches for measuring and predicting genetic patterns. The importance of simulation studies for this specific research has been emphasized in a number of recent articles (e.g., Balkenhol 2009a; Epperson 2010). Indeed, many of the major questions in landscape genetics require the development and application of sophisticated simulation tools to explore gene flow, genetic drift, mutation and natural selection in landscapes with a wide range of spatial and temporal complexities. In this issue, Jaquiéry (2011) provide an excellent example of such a simulation study for landscape genetics. Using a metapopulation simulation design and a novel 'scale of phenomena' approach, Jaquiéry (2011) demonstrate the utility and limitations of genetic distances for inferring landscape effects on effective dispersal. © 2011 Blackwell Publishing Ltd.

Reissmann M.,Humboldt University of Berlin | Ludwig A.,Leibniz Institute for Zoo and Wildlife Research
Seminars in Cell and Developmental Biology | Year: 2013

The characterisation of the pleiotropic effects of coat colour-associated mutations in mammals illustrates that sensory organs and nerves are particularly affected by disorders because of the shared origin of melanocytes and neurocytes in the neural crest; e.g. the eye-colour is a valuable indicator of disorders in pigment production and eye dysfunctions. Disorders related to coat colour-associated alleles also occur in the skin (melanoma), reproductive tract and immune system. Additionally, the coat colour phenotype of an individual influences its general behaviour and fitness. Mutations in the same genes often produce similar coat colours and pleiotropic effects in different species (e.g., KIT [reproductive disorders, lethality], EDNRB [megacolon] and LYST [CHS]). Whereas similar disorders and similar-looking coat colour phenotypes sometimes have a different genetic background (e.g., deafness [. EDN3/EDNRB, MITF, PAX and SNAI2] and visual diseases [. OCA2, RAB38, SLC24A5, SLC45A2, TRPM1 and TYR]). The human predilection for fancy phenotypes that ignore disorders and genetic defects is a major driving force for the increase of pleiotropic effects in domestic species and laboratory subjects since domestication has commenced approximately 18,000 years ago. © 2013 Elsevier Ltd.

News Article | August 26, 2016
Site: phys.org

The gibbon ape leukemia virus (GALV) is a medically important tool in cancer therapies. GALV is a retrovirus pathogenic to its host species, the southeast Asian lar gibbon (Hylobates lar) and thought to have originated from a cross-species transmission and may not originally be a primate virus at all. An international research team headed by the German Leibniz Institute for Zoo and Wildlife Research (IZW) screened a wide range of rodents from southeast Asia for GALV-like sequences. The discovery of a new GALV in the grassland melomys (Melomys burtoni) from Indonesian New Guinea supports the hypothesis that this host species, and potentially related rodent lineages in Australia and Papua New Guinea, may have played a key role in the spread of GALV-like viruses. The findings were published in the scientific journal Journal of Virology. The scientists found that rodents from Indonesian New Guinea possibly contributed as vectors to a cross-species transmission leading to the infection of gibbons with the gibbon ape leukemia virus (GALV) and koalas with the koala retrovirus (KoRV). GALV is a retrovirus which causes a cancer (hematopoietic neoplasms) in captive colonies of gibbons. However, GALV has never been isolated from wild primates that did not have a captive origin. This suggests that some other species in contact with captive gibbons are the source of GALV. KoRV is a retrovirus closely related to GALV and therefore the two viruses share a common ancestor. Since koalas and gibbons do not overlap in distribution, a direct natural transmission between koalas and gibbons is unlikely. It is therefore probable that one or more mobile and widely distributed host species such as rodents carry GALV- and KoRV-like viruses and infected koalas and gibbons independently. The findings of this study are consistent with this hypothesis. The scientists screened twenty-six southeastern Asian rodent species for the presence of KoRV- and GALV-like sequences using next generation high-throughput genetic sequencing techniques. Their aim was to identify potential intermediate hosts of GALV or KoRV like viruses. Only one rodent species was positive: a newly discovered subspecies of the grassland melomys (Melomys burtoni), also called the grassland mosaic-tailed rat, from Indonesian New Guinea. The samples of this species yielded an endogenous provirus very closely related to GALV, indicating that the grassland melomys may serve as intermediate host for GALV- and KoRV-like viruses. Retroviruses use proteins (called receptors) on the host cell surface to gain entrance to host cells. Changes in the virus or in the receptor can prevent specific viruses from infecting some types of cells or infecting some species. The sequence of the critical receptor for GALV infection in the grassland melomys is consistent with the susceptibility of the species to GALV infection. Since the grassland melomys is not present in mainland southeastern Asia, where gibbons are distributed, the newly discovered virus cannot be a direct GALV progenitor. However, the discovery of such a close GALV relative in Indonesian New Guinea, and specifically in a transitional zone between Asia and Australia (Wallacea), may be relevant to the cross-species transmission to gibbons in southeastern Asia. Indeed, it is possible that the grassland melomys is one of several intermediate hosts which contributed to the cross-species transmission with koalas and gibbons as final end hosts. It is also possible that the viruses that gave rise to GALV and KoRV may be circulating in Wallacea in more mobile species which overlap with the grassland melomys. Further research in this part of the world will likely continue to yield new viruses belonging to this unique retroviral group. Explore further: Decisions and stress and adolescents More information: Niccolo Alfano et al. An endogenous gibbon ape leukemia virus (GALV) identified in a rodent (subsp.) from Wallacea (Indonesia), Journal of Virology (2016). DOI: 10.1128/JVI.00723-16

Wilting A.,Leibniz Institute for Zoo and Wildlife Research
Raffles Bulletin of Zoology | Year: 2016

The flat-headed cat Prionailurus planiceps is classified as one of the most threatened cat species in the world. Its range is restricted to southern Thailand, peninsular Malaysia and the two largest Sunda Islands, Borneo and Sumatra. Its association with wetlands and lowland areas puts great pressure on this species, because these habitats are most threatened by degradation and agricultural conversions. Borneo has been identified as the stronghold for flat-headed cat. Of 140 flat-headed cat occurrence records for Borneo, 50 (Balanced Model) or 76 (Spatial Filtering Model) were used to estimate potential habitat suitability. Although we predicted suitable habitat for the flat-headed cat scattered across the lowlands of Borneo, some large lowland areas are predicted to be unsuitable, a likely consequence of forest conversion to oil palm plantations. Of particular predicted importance are forests in Brunei Darussalam, the Sabangau National Park and surrounding forest complex in Central Kalimantan and forests in North Kalimantan, as well as the central forest block in Sabah. The main threat to the flat-headed cat is on-going transformation of forested areas to monoculture plantations, as the species appears unable to use these human-dominated habitats. Of particular importance for long-term survival of flat-headed cat is conservation of land near rivers and peat swamp forests. © 2016 National University of Singapore.

Wilting A.,Leibniz Institute for Zoo and Wildlife Research
Raffles Bulletin of Zoology | Year: 2016

The Bornean ferret badger Melogale everetti is one of the least known Bornean carnivores, and is currently classified as Data Deficient on The IUCN Red List of Threatened Species. Endemic to Borneo, it is associated with upland and highland forests in and around Kinabalu Park and Crocker Range Park. Of 52 Bornean ferret badger occurrence records, 14 were used to estimate potential habitat suitability. This species is likely to be confined to a very small range in western Sabah, potentially the smallest distribution range of any carnivore species in South-east Asia. All occurrence records were above 500 m elevation, which suggests that this species is restricted to upland and highland forests. Areas of particular importance predicted for survival of this species are Kinabalu Park, Crocker Range Park, and unprotected areas and commercial forest reserves east of Crocker Range Park. Because of the low number of recent records, the main threats to the Bornean ferret badger are unknown, but the transformation of forested areas to monoculture plantations and perhaps incidental hunting are likely to have negative effects on this species. As an upland and high-elevation specialist, climate change might also become an important future threat. Of particular importance for long-term survival of the Bornean ferret badger is an improved understanding of its current status, ecology and the threats it actually faces (if any). © 2016 National University of Singapore.

Kramer-Schadt S.,Leibniz Institute for Zoo and Wildlife Research | Wilting A.,Leibniz Institute for Zoo and Wildlife Research
Raffles Bulletin of Zoology | Year: 2016

South-east Asian mammals face a particularly severe threat of extinction. Borneo, the third largest island in the world, is located in the centre of South-east Asia. It harbours more endemic carnivores than does any other island except Madagascar. Almost half the Bornean carnivore species have been classified by The IUCN Red List of Threatened Species as threatened. Because little is known about most Bornean carnivores, predicting their spatial distribution is important for management strategies to improve the conservation of these species. As a part of the 1st Borneo Carnivore Symposium (BCS) we started to assemble a knowledge base of Bornean carnivores. We established the Borneo Carnivore Database which contains the previously largely fragmented occurrence records of carnivores on the island and then used these records to predict the distribution of 20 Bornean carnivores (all native species except sun bear Helarctos malayanus and the four otter species, Eurasian otter Lutra lutra, Asian smallclawed otter Aonyx cinereus, hairy-nosed otter Lutra sumatrana and smooth-coated otter Lutrogale perspicillata). We describe general considerations – the underlying assumptions, advantages, and most importantly the limitations and constraints – of species distribution modelling. We then summarise the methodological framework of our modelling approach and results of the sensitivity analyses. We emphasise that despite the extensive efforts to compile existing information, so few or spatially biased occurrence records exist for some species that the model outcomes presented in this journal issue must be interpreted cautiously. We recommend using new data as they become available to test our projections and improve our understanding of carnivore distributions on Borneo. © 2016 National University of Singapore.

Roellig K.,Leibniz Institute for Zoo and Wildlife Research
Nature communications | Year: 2010

The concept of superfetation, a second conception during pregnancy, has been controversial for a long time. In this paper we use an experimental approach to demonstrate that female European brown hares (Lepus europaeus) frequently develop a second pregnancy while already pregnant and thereby increase their reproductive success. After a new, successful copulation, we confirmed additional ovulations before parturition in living, late-pregnant females by detecting a second set of fresh corpora lutea using high-resolution ultrasonography. The presence of early embryonic stages in the oviduct, demonstrated by oviduct flushing, next to fully developed fetuses in the uterus is best explained by passage of semen through the late-pregnant uterus; this was confirmed by paternity analysis using microsatellite profiling. Subsequent implantation occurred after parturition. This superfetation, categorized as superconception, significantly increased litter size and permitted females to produce up to 35.4% more offspring per breeding season. It is therefore most likely an evolutionary adaptation.

Honer O.P.,Leibniz Institute for Zoo and Wildlife Research
Nature communications | Year: 2010

Life history theory predicts that mothers should provide their offspring with a privileged upbringing if this enhances their offspring's and their own fitness. In many mammals, high-ranking mothers provide their offspring with a privileged upbringing. Whether dispersing sons gain fitness benefits during adulthood from such privileges (a 'silver spoon' effect) has rarely been examined. In this paper, we show that in the complex, female-dominated society of spotted hyaenas, high-born sons grew at higher rates, were more likely to disperse to clans offering the best fitness prospects, started reproducing earlier and had a higher reproductive value than did lower-born sons. This illustrates the evolutionary importance of maternal effects even in societies in which male size or fighting ability does not influence fitness. By demonstrating for the first time in a non-human mammal that maternal status influences immigration patterns, the study also advances our understanding of two key ecological and evolutionary processes, dispersal and habitat selection.

Voigt C.C.,Leibniz Institute for Zoo and Wildlife Research
Biotropica | Year: 2010

Stable carbon isotope ratios (δ13C) of plants increase linearly from ground to canopy. Accordingly, I used δ13C for estimating strata use of fig-eating bats. Data suggest that, overall, bats commuted at lower but fed at higher forest strata, and that small bats foraged at lower forest strata than large bats. © 2010 The Author(s). Journal compilation © 2010 by The Association for Tropical Biology and Conservation.

Muhldorfer K.,Leibniz Institute for Zoo and Wildlife Research
Zoonoses and Public Health | Year: 2013

The occurrence of emerging infectious diseases and their relevance to human health has increased the interest in bats as potential reservoir hosts and vectors of zoonotic pathogens. But while previous and ongoing research activities predominantly focused on viral agents, the prevalence of pathogenic bacteria in bats and their impact on bat mortality have largely neglected. Enteric pathogens found in bats are often considered to originate from the bats' diet and foraging habitats, despite the fact that little is known about the actual ecological context or even transmission cycles involving bats, humans and other animals like pets and livestock. For some bacterial pathogens common in human and animal diseases (e.g. Pasteurella, Salmonella, Escherichia and Yersinia spp.), the pathogenic potential has been confirmed for bats. Other bacterial pathogens (e.g. Bartonella, Borrelia and Leptospira spp.) provide evidence for novel species that seem to be specific for bat hosts but might also be of disease importance in humans and other animals. The purpose of this review is to summarize the current knowledge of bacterial pathogens identified in bats and to consider factors that might influence the exposure and susceptibility of bats to bacterial infection but could also affect bacterial transmission rates between bats, humans and other animals. © 2012 Blackwell Verlag GmbH.

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