Data/hora: 10/06/2024 18:33:42

Provedor de dados: 	103	
País: 	Brazil	
Título: 	Genetic consequences of population subdivision: the marsupial Micoureus paraguayanus (Mammalia: Didelphimorphia) as a case study	
Autores: 	Brito,Daniel.	
Data: 	2009-12-01	
Ano: 	2009	
Palavras-chave: 	Genetic drift; Genetic load; Habitat fragmentation; Inbreeding; Metapopulation; Population viability analysis.	
Resumo: 	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 allelic diversity declined rapidly when a population was subdivided. Genetic and demographic stochasticity diminished the effectiveness of selection against recessive lethal alleles. Dispersal partly reversed the impacts of population subdivision. However, even high rates of dispersal did not eliminate demographic fluctuations or prevent extinction. Although gene flow largely prevented genetic divergence between populations, dispersal did not prevent heterozygosity from being lost more rapidly in subdivided populations than in single populations of equivalent total size. The dynamics of small, fragmented populations were critically dependent on interactions between demographic and genetic processes. Populations of M. paraguayanus may have to be relatively large and continuous to avoid significant losses of genetic diversity.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702009000400013	
Editor: 	Sociedade Brasileira de Zoologia	
Relação: 	10.1590/S1984-46702009000400013	
Formato: 	text/html	
Fonte: 	Zoologia (Curitiba)  v.26 n.4 2009	
Fonte: 	info:eu-repo/semantics/openAccess