Genetic inference of the mating system of free-ranging domestic dogs

Domestication has greatly changed the social and reproductive behavior of dogs relative to that of wild members of the genus Canis, which typically exhibit social monogamy and extended parental care. Unlike a typical gray wolf pack that consists of a single breeding pair and their offspring from multiple seasons, a group of free-ranging dogs (FRDs) can include multiple breeding individuals of both sexes. To understand the consequences of this shift in reproductive behavior, we reconstructed the genetic pedigree of an FRD population and assessed the kinship patterns in social groups, based on genome-wide single-nucleotide polymorphism genotypes. Consistent with behavioral observations, the mating system of the study population was characterized by polygynandry. Instead of the discreet family units observed in wolves, FRDs were linked by a network of kinship relationships that spread across packs. However, we also observed reproduction of the same male-female pairs in multiple seasons, retention of adult offspring in natal packs, and dispersal between neighboring packs-patterns in common with wolves. Although monogamy is the predominant mating system in wolves, polygyny and polyandry are occasionally observed in response to increased food availability. Thus, polygynandry of domestic dogs was likely influenced by the shift in ecological niche from an apex predator to a human commensal.

Automated summary

Through reconstructing the genetic pedigree and assessing kinship patterns, it was found that free-ranging dogs exhibit a polygynandrous mating system with a network of kinship relationships across packs. While retaining some common reproductive patterns with wolves, such as repeated mating of the same pairs and adult offspring staying within packs, the shift in ecological niche from apex predator to human commensal likely influenced this behavior.