SREL Reprint #3588

Differing, multiscale landscape effects on genetic diversity and differentiation in eastern chipmunks

Elizabeth M. Kierepka1, Sara J. Anderson2, Robert K. Swihart3, and Olin E. Rhodes Jr4

1Veterinary Genetics Laboratory, University of California, Davis, Davis, CA 95616, USA
2Biosciences Department, Minnesota State University Moorhead, 1104 7th Ave, Moorhead, MN 56563, USA
3Department of Forestry and Natural Resources, Purdue University,
715 W. State Street, West Lafayette, IN 47907, USA
4Savannah River Ecology Laboratory, University of Georgia, PO Drawer E, Aiken, SC 29802, USA

Abstract: Understanding how habitat loss and fragmentation impact genetic variation is a major goal in landscape genetics, but to date, most studies have focused solely on the correlation between intervening matrix and genetic differentiation at a single spatial scale. Several caveats exist in these study designs, among them is the inability to include measures of genetic diversity in addition to differentiation. Both genetic metrics help predict population persistence, but are expected to function at differing spatial scales, which requires a multiscale investigation. In this study, we sampled two distinct spatial scales in 31 independent landscapes along a gradient of landscape context (i.e., forest amount, configuration, and types of intervening matrix) to investigate how landscape heterogeneity influences genetic diversity and differentiation in the forest-associated eastern chipmunk (Tamias striatus). Overall, quality of intervening matrix was correlated with genetic differentiation at multiple spatial scales, whereas only configuration was associated with regional scale genetic diversity. Habitat amount, in contrast, did not influence genetic differentiation or diversity at either spatial scale. Based on our findings, landscape effects on genetic variation appears to differ based on spatial scale, the type of genetic response variable, and random variation among landscapes, making extrapolation of results from single scale, unreplicated studies difficult. We encourage landscape geneticists to utilize multiscale, replicated landscapes with both genetic diversity, and differentiation to gain a more comprehensive understanding of how habitat loss and fragmentation influence genetic variation.

SREL Reprint #3588

Kierepka, E. M., S. J. Anderson, R. K. Swihart, and O. E. Rhodes Jr. 2020. Differing, multiscale landscape effects on genetic diversity and differentiation in eastern chipmunks. Heredity 124(2020): 457-468.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).