Biological Correlates with Degree of Introgressive Hybridization between Coyotes Canis latrans and Wolves Canis sp. in Pennsylvania, U.S.A.

Abstract. Descendants of introgressive hybridization between species may have evolutionary advantages over their parental species. Prior studies have documented evidence of introgressive hybridization between coyotes, dogs, grey wolves and eastern wolves. This study attempts to attribute morphology and pelage patterns of Pennsylvania coyotes to sex, ecoregion, and the degree of coyote-wolf introgressive hybridization. A total of 192 coyotes were genotyped at 63 ancestry informative SNPS to determine the percent of coyote genome attributable to wolf origin (percent wolf). Females had higher percent wolf than males, which could be the result of lower survivorship in hybrid males. Percent wolf, sex, and ecoregion each were found to independently influence size using general linear model analysis, and the effect of sex was most pronounced. Coyotes from Northeastern and northcentral ecoregions of Pennsylvania were larger in size and possessed a higher percent wolf. Moreover, coyotes with higher percent wolf were larger, less red in some parts of their pelage, and had a different pelage patchiness composition. This correlates with previous studies that showed ecoregions with increased deer density correlated to coyotes with higher percent wolf. Size and percent wolf may be adaptively advantageous in Northeastern Pennsylvania where there is a relatively high deer population abundance. Furthermore, the degree of redness within coyotes may be used as an indicator for introgression levels for population managers, aiding in understanding the shifting ecological role of coyotes.