Coyotes demonstrate how habitat specialization by individuals of a generalist species can diversify populations in a heterogeneous ecoregion.
The tendency for individuals to disperse into habitat similar to their natal habitat has been observed in a wide range of species, although its population genetic consequences have received little study. Such behavior could lead to discrete habitat-specific population subdivisions even in the absence of physical dispersal barriers or habitat gaps. Previous studies of coyotes have supported this hypothesis in a small region of California, but its evolutionary significance ultimately depends on the extent and magnitude of habitat-specific subdivision. Here, we investigated these questions using autosomal, Y chromosome, and mitochondrial markers and >2,000 coyotes from a broad region, including 2 adjacent ecoregions with contrasting levels of habitat heterogeneity--the California Floristic Province (CFP) (heterogeneous landscape) and the Desert-Prairie ecoregion (DPE) (homogeneous landscape). Consistent with predictions, we found a close correspondence between population genetic structure and habitat subdivisions throughout the CFP and virtual panmixia over the larger DPE. Conversely, although genetic diversity was similar in these 2 ecoregions overall, it was lower within sites of the CFP, as would be the expected consequence of greater genetic drift within subregions. The magnitude of habitat-specific genetic subdivisions (i.e., genetic distance) in the CFP varied considerably, indicating complexity (e.g., asymmetric gene flow or extinction/recolonization), but, in general, was higher than that due to geographic distance or recent human-related barriers. Because habitat-specific structure can enhance a species' adaptive potential and resilience to changing environments, these findings suggest the CFP may constitute an evolutionarily important portion of the range for coyotes and sympatric species exhibiting habitat-specific population structure.
Sacks
Benjamin N
BN
Veterinary Genetics Laboratory, University of California, Davis, CA, USA. bnsacks@ucdavis.edu
Bannasch
Danika L
DL
Chomel
Bruno B
BB
Ernest
Holly B
HB
D000818:Animals; D002140:California; D046029:Coyotes / Q000235:genetics*; D017753:Ecosystem; D004777:Environment; D051456:Gene Flow; D005787:Gene Frequency; D008040:Genetic Linkage; D005819:Genetic Markers; D005828:Genetics, Population; D005838:Genotype; D006801:Humans; D018895:Microsatellite Repeats / Q000235:genetics
D005819:Genetic Markers