Genetic and morphometric divergence of an invasive bird: the introduced house sparrow (Passer domesticus) in Brazil.

Autor: Marcos R Lima, Regina H F Macedo, Thaís L F Martins, Aaron W Schrey, Lynn B Martin, Staffan Bensch
Jazyk: angličtina
Rok vydání: 2012
Předmět:
Zdroj: PLoS ONE, Vol 7, Iss 12, p e53332 (2012)
Druh dokumentu: article
ISSN: 1932-6203
DOI: 10.1371/journal.pone.0053332
Popis: Introduced species are interesting systems for the study of contemporary evolution in new environments because of their spatial and temporal scales. For this study we had three aims: (i) to determine how genetic diversity and genetic differentiation of introduced populations of the house sparrow (Passer domesticus) in Brazil varies with range expansion, (ii) to determine how genetic diversity and differentiation in Brazil compares to ancestral European populations; and (iii) to determine whether selection or genetic drift has been more influential on phenotypic divergence. We used six microsatellite markers to genotype six populations from Brazil and four populations from Europe. We found slightly reduced levels of genetic diversity in Brazilian compared to native European populations. However, among introduced populations of Brazil, we found no association between genetic diversity and time since introduction. Moreover, overall genetic differentiation among introduced populations was low indicating that the expansion took place from large populations in which genetic drift effects would likely have been weak. We found significant phenotypic divergence among sites in Brazil. Given the absence of a spatial genetic pattern, divergent selection and not genetic drift seems to be the main force behind most of the phenotypic divergence encountered. Unravelling whether microevolution (e.g., allele frequency change), phenotypic plasticity, or both mediated phenotypic divergence is challenging and will require experimental work (e.g., common garden experiments or breeding programs).
Databáze: Directory of Open Access Journals