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| Registros recuperados: 14 | |
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| Dunham, Jason; University of Nevada-Reno; jdunham@proaxis.com; Peacock, Mary; University of Nevada-Reno; mpeacock@scs.unr.edu; Tracy, C. Richard; University of Nevada-Reno; dtracy@unr.edu; Nielsen, Jennifer; Stanford University; jnielsen@leland.stanford.edu; Vinyard, Gary; University of Nevada-Reno; gvinyard@med.unr.edu. |
| Risks of population extinction have been estimated using a variety of methods incorporating information from different spatial and temporal scales. We briefly consider how several broad classes of extinction risk assessments, including population viability analysis, incidence functions, and ranking methods integrate information on different temporal and spatial scales. In many circumstances, data from surveys of neutral genetic variability within, and among, populations can provide information useful for assessing extinction risk. Patterns of genetic variability resulting from past and present ecological and demographic events, can indicate risks of extinction that are otherwise difficult to infer from ecological and demographic analyses alone. We provide... |
| Tipo: Peer-Reviewed Reports |
Palavras-chave: Extinction risk; Genetic variation; Incidence function analysis; Population viability analysis; Ranking methods; Risk assessment; Spatial scale; Temporal scale.. |
| Ano: 1999 |
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| Brook, Barry W; Northern Territory University; barry.brook@ntu.edu.au; Tonkyn, David W; Clemson University; tdavid@clemson.edu; O'Grady, Julian J; Macquarie University; jogrady@rna.bio.mq.edu.au; Frankham, Richard; Macquarie University; rfrankha@rna.bio.mq.edu.au. |
| Wild populations face threats both from deterministic factors, e.g., habitat loss, overexploitation, pollution, and introduced species, and from stochastic events of a demographic, genetic, and environmental nature, including catastrophes. Inbreeding reduces reproductive fitness in naturally outbreeding species, but its role in extinctions of wild populations is controversial. To evaluate critically the role of inbreeding in extinction, we conducted realistic population viability analyses of 20 threatened species, with and without inbreeding depression, using initial population sizes of 50, 250, and 1000. Inbreeding markedly decreased median times to extinction by 28.5, 30.5, and 25% for initial populations of 50, 250, and 1000, respectively, and the... |
| Tipo: Peer-Reviewed Reports |
Palavras-chave: Endangered species; Inbreeding depression; Life histories; Median time to extinction; Population viability analysis; Purging. |
| Ano: 2002 |
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| Brook, Barry W; Northern Territory University; barry.brook@ntu.edu.au; Burgman, Mark A; University of Melbourne; m.burgman@botany.unimelb.edu.au; Frankham, Richard; Macquarie University; rfrankha@rna.bio.mq.edu.au. |
| Population viability analysis (PVA) is used in conservation biology to predict extinction probabilities for threatened species. Previous studies have revealed large differences between the predictions of PVA modeling packages, but these comparisons included a range of nonstandard factors. A standardized comparison of five PVA packages (GAPPS, INMAT, RAMAS Metapop, RAMAS Stage, and VORTEX) was conducted on six examples (two mammals, two birds, one reptile, and a hypothetical bird/mammal-like life history). The individual-based packages (GAPPS and VORTEX) predicted a consistently higher risk of extinction than their matrix-based counterparts (INMAT and the RAMAS programs). This arose as only the former considered the effect of demographic stochasticity in... |
| Tipo: Peer-Reviewed Reports |
Palavras-chave: Demographic stochasticity; Extinction risk; Individual-based models; Matrix-based models; Model comparison; Parameter estimation; Population viability analysis; Sex ratio. |
| Ano: 2000 |
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| Brito,Daniel. |
| Habitat fragmentation may cause population subdivision, affecting genetic variation, leading to heterozygosity loss and increased inbreeding, and contributing to population extinction. However, some genetic models have shown that under some conditions, population subdivision can favor heterozygosity and allelic diversity, and small populations may adapt to inbreeding. Here I investigate the relationship between population subdivision and genetic diversity for the marsupial Micoureus paraguayanus (Tate, 1931) using the program Vortex. Hypothetical populations of 100 and 2000 individuals were partitioned into 1, 2, 5 or 10 populations that were linked by varying rates of dispersal and also by sex-biased dispersal. Results suggested that heterozygosity and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Genetic drift; Genetic load; Habitat fragmentation; Inbreeding; Metapopulation; Population viability analysis. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702009000400013 |
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| Omar,Suliman Y. Al; Alkuriji,Afrah; Alwasel,Saleh; Dar,javid Ahmed; Alhammad,Alwaleed; Christmas,Stephen; Mansour,Lamjed. |
| Abstract Killer Cell Immunoglobulin-like Receptors (KIR) have been used as good markers for the study of genetic predisposition in many diseases and in human genetic population dynamics. In this context, we have investigated the genetic diversity of KIR genes and their main HLA class I ligands in Saudi population and compared the data with other studies of neighboring populations. One hundred and fourteen randomly selected healthy Saudi subjects were genotyped for the presence or absence of 16 KIR genes and their HLA-C1, -C2, -Bw4Thr80 and Bw4Ile80 groups, using a PCR-SSP technique. The results show the occurrence of the framework genes (3DL2, 3DL3 and 2DL4) and the pseudogenes (2DP1 and 3DP1) at highest frequencies. All inhibitory KIR (iKIR) genes... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: KIR diversity; Gene polymorphism; Molecular evolution; PCR SSP; Population viability analysis. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572016000100014 |
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| Hilbers, Jelle P.; Santini, Luca; Visconti, Piero; Schipper, Aafke M.; Pinto, Cecilia; Rondinini, Carlo; Huijbregts, Mark A. J.. |
| Conservation planning and biodiversity assessments need quantitative targets to optimize planning options and assess the adequacy of current species protection. However, targets aiming at persistence require population-specific data, which limits their use in favor of fixed and non-specific targets, likely leading to unequal distribution of conservation efforts among species. Here we propose a method to derive equitable population targets, which are quantitative targets of population size that ensure equal probabilities of persistence across a set of species, and can be easily inferred from species-specific traits. We applied population dynamics models across a range of life-history traits representative for mammals, and estimated minimum viable population... |
| Tipo: Text |
Palavras-chave: Allometry; Conservation biology; Conservation target; Extinction; Minimum viable population; Population viability analysis; Wildlife; Wildlife management. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00353/46387/46013.csv |
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| Nyhus, Philip J.; Environmental Studies Program, Colby College; pjnyhus@colby.edu; Lacy, Robert; Chicago Zoological Society; rlacy@ix.netcom.com; Westley, Frances R; Nelson Institute for Environmental Studies, University of Wisconsin-Madison; westley@wisc.edu; Miller, Philip; Conservation Breeding Specialist Group (SSC/IUCN); pmiller@cbsg.org; Vredenburg, Harrie; Haskayne School of Business, University of Calgary; harrie.vredenburg@haskayne.ucalgary.ca; Paquet, Paul; Faculty of Environmental Design, University of Calgary; ppaquet@sasktel.net; Pollak, John; Visual Biosystems; jp@visualbiosystems.com. |
| Tipo: Peer-Reviewed Reports |
Palavras-chave: Biocomplexity; Endangered species; Human dimension; Meta-model; Population viability analysis; Risk assessment; VORTEX.. |
| Ano: 2007 |
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| van der Ree, Rodney; Australian Research Centre for Urban Ecology, Royal Botanic Gardens Melbourne; rvdr@unimelb.edu.au; Heinze, Dean; Department of Primary Industries and Water; Dean.Heinze@dpiw.tas.gov.au; McCarthy, Michael; Australian Research Centre for Urban Ecology; mamcca@unimelb.edu.au; Mansergh, Ian; Department of Sustainability and Environment; ian.mansergh@dse.vic.gov.au. |
| Roads and traffic are pervasive components of landscapes throughout the world: they cause wildlife mortality, disrupt animal movements, and increase the risk of extinction. Expensive engineering solutions, such as overpasses and tunnels, are increasingly being adopted to mitigate these effects. Although some species readily use such structures, their success in preventing population extinction remains unknown. Here, we use population viability modeling to assess the effectiveness of tunnels for the endangered Mountain Pygmy-possum (Burramys parvus) in Australia. The underpasses reduced, but did not completely remove, the negative effects of a road. The expected minimum population size of a “reconnected” population remained 15% lower... |
| Tipo: Peer-Reviewed Reports |
Palavras-chave: Barrier effect; Burramys; Population-level impacts; Population viability analysis; Road ecology; Underpass; Wildlife crossing structure. |
| Ano: 2009 |
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| Registros recuperados: 14 | |
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