Genetic population structure and relatedness in the narrow‐striped mongoose (Mungotictis decemlineata), a social Malagasy carnivore with sexual segregation

Abstract

Information on the genetic structure of animal populations can allow inferences about mechanisms shaping their social organization, dispersal, and mating system. The mongooses (Herpestidae) include some of the best‐studied mammalian systems in this respect, but much less is known about their closest relatives, the Malagasy carnivores (Eupleridae), even though some of them exhibit unusual association patterns. We investigated the genetic structure of the Malagasy narrow‐striped mongoose (Mungotictis decemlineata), a small forest‐dwelling gregarious carnivore exhibiting sexual segregation. Based on mtDNA and microsatellite analyses, we determined population‐wide haplotype structure and sex‐specific and within‐group relatedness. Furthermore, we analyzed parentage and sibship relationships and the level of reproductive skew. We found a matrilinear population structure, with several neighboring female units sharing identical haplotypes. Within‐group female relatedness was significantly higher than expected by chance in the majority of units. Haplotype diversity of males was significantly higher than in females, indicating male‐biased dispersal. Relatedness within the majority of male associations did not differ from random, not proving any kin‐directed benefits of male sociality in this case. We found indications for a mildly promiscuous mating system without monopolization of females by males, and low levels of reproductive skew in both sexes based on parentages of emergent young. Low relatedness within breeding pairs confirmed immigration by males and suggested similarities with patterns in social mongooses, providing a starting point for further investigations of mate choice and female control of reproduction and the connected behavioral mechanisms. Our study contributes to the understanding of the determinants of male sociality in carnivores as well as the mechanisms of female competition in species with small social units.

The evolution of matrilineal social systems in fissiped carnivores

“…As in herpestids, group living in euplerids has antipredator and resource defence benefits [46]. Female narrow-striped mongooses (Mungotictis decemlineata) live in small, philopatric groups of related females and their offspring [47]. Group members den together but do not provide alloparental care [47].…”

“…Female narrow-striped mongooses (Mungotictis decemlineata) live in small, philopatric groups of related females and their offspring [47]. Group members den together but do not provide alloparental care [47]. Their social organization is matrilineal, with neighbouring groups sharing the same haplotypes [47].…”

“…Group members den together but do not provide alloparental care [47]. Their social organization is matrilineal, with neighbouring groups sharing the same haplotypes [47].…”

Evidence for an extreme founding effect in a highly successful invasive species

“…Purportedly introduced as a breeding pair from Sidi Ifni, Morocco in 1965 [19], the current island population has had remarkable success in population growth (estimated one million) and range expansion [20,21]. We examined the mitochondrial and nuclear diversity of A. getulus to resolve any discrepancies between the two differently inherited genomes [22][23][24].…”