Introgression of Coyote Mitochondrial DNA Into Sympatric North American Gray Wolf Populations

Abstract

Mitochondrial DNA genotypes of Canis lupus and C. latrans from throughout North America were determined using restriction fragment length polymorphisms. Of the 13 genotypes found among the wolves, 7 are clearly of coyote origin, indicating that genetic transfer of coyote mtDNA into wolf populations has occurred through hybridization. No coyotes sampled have a wolf-derived mtDNA genotype. Wolves possessing coyote-derived genotypes are confined to a contiguous geographic region in Minnesota, Ontario, and Quebec; frequency of coyote-type mtDNA in these wolf populations is high (>50%). The ecological history of the hybrid zone suggests that hybridization is taking place in regions where coyotes have only recently become abundant following conversion of forests to farmlands. Dispersing male wolves unable to find conspecific mates may be pairing with female coyotes in deforested areas bordering wolf territories. "