Microsatellite analysis of multiple paternity and male reproductive success in the promiscuous snowshoe hare

Abstract

Few genetic studies have addressed patterns of paternity in promiscuous mammals. I used microsatellite DNA primers developed in the European rabbit to analyze paternity in the promiscuous snowshoe hare (Lepus americanus). Sixty-five offspring, their 12 mothers, and their 24 putative fathers were genotyped at seven polymorphic loci (3–22 alleles/locus). Paternal allele counts and likelihood-based paternity assignments confirmed that multiple paternity occurs in snowshoe hare litters. However, the estimated frequency of multiple paternity was lower than expected in an unstructured promiscuous mating system. A relatively low variance in male reproductive success indicated that no males dominated paternity. A few males did achieve significantly more paternities than average, largely by fathering one or two complete litters rather than a few offspring in many litters. The results suggest that successful multiple mating is limited among both male and female snowshoe hares. An important role for pre- and (or) post-copulatory competition is implied.