Population subdivision of Mus musculus in an agrarian landscape. Consequences for control

LEÓN V; FRASCHINA J; BUSCH M

CANADIAN JOURNAL OF ZOOLOGY

NATL RESEARCH COUNCIL CANADA-N R C RESEARCH PRESS

Año: 2010 vol. 88 p. 427 - 435

0008-4301

In Argentina agroecosystems, Mus musculus (Linnaeus, 1758) shows a discontinuous distribution, with high abundances on farms but scarce in cropfields. In farms, its abundance could be affected by the movements of mice among them. Our hypotheses were: 1) there are not movements among farms, and the alternative: 2) rodents move among farms. This last hypothesis has two sub hypotheses: 2.1) Rodents move actively, or 2.2) movements are passive, through human transport. The prediction from hypothesis 1) is that there will be genetic subdivision among farms, and genetic divergence will be independent of geographic distance. From hypothesis 2.1) genetic differentiation will be correlated to geographic distance. From hypothesis 2.2) we expect an absence of genetic subdivision, or that differentiation may be related to human movements. We examined genetic variation among farms (n = 15) using six microsatellite loci, and we tracked movements of 36 individuals in five farms  using fluorescent powders. Mus musculus populations showed genetic differentiation at both farm and shed scales. Genetic and geographic distances were significantly correlated. There was no evidence of passive movements of rodents and the movements shown by  fluorescent powder within farms were short. According to these results,  hypothesis 2.1 is favoured.