Socio‐genetic structure and mating system of a wild boar population

Abstract

Wild boars Sus scrofa have a social organization based on female groups that can include several generations of adults and offspring, and are thus likely matrilineal. However, little is known about the degree of relatedness between animals living in such groups or occupying the same core area of spatial activity. Also, polygynous male mating combined with matrilineal female groups can have strong influences on the genetic structure of populations. We used microsatellite genotyping combined with behavioral data to investigate the fine-scale population genetic structure and the mating system of wild boars in a multi-year study at Chaˆteau-villain-Arc-en-Barrois (France). According to spatial genetic autocorrelation, females in spatial proximity were significantly inter-related. However, we found that numerous males contributed to the next generation, even within the same social group. Based on our genetic data and behavioral observations, wild boars in this population appear to have a low level of polygyny associated with matrilineal female groups, and infrequent multiple paternity. Mortality due to hunting may facilitate the breakup of what historically has been a more predominantly polygynous mating system, and likely accelerates the turnover of adults within the matrilineal groups.

Mitochondrial and nuclear DNA analyses reveal pronounced genetic structuring in Tunisian wild boar Sus scrofa

“…Differentiation estimates obtained with mtDNA were higher than those obtained with microsatellite data in our study area. Mutually non-exclusive explanations that might account for this discrepancy are (1) differential dispersal between the sexes-as a polygynous mammal, the wild boar is characterised by strong female philopatry and male-biased dispersal (Poteaux et al 2009); (2) differences in effective population size between the two marker systems; and (3) F ST values obtained with microsatellite data might be an underestimate because of the high polymorphism of microsatellites leading to a large amount of genetic diversity within populations (Hedrick 1999;Balloux and LugonMoulin 2002). The STRUCTURE analysis yielded a clear split between the indigenous northern population and the recently established southern one, but also suggested a certain amount of admixture.…”

Invasion ecology of wild pigs (Sus scrofa) in Florida, USA: the role of humans in the expansion and colonization of an invasive wild ungulate

“…Aggregation of related individuals in family groups, high levels of female philopatry, and a few polygynous males siring the next generations, contribute to increase the genetic similarities among individuals of the same group (Gabor et al 1999;Hampton et al 2004;Kaminski et al 2005;Poteaux et al 2009). Considering our collection scheme of wild pigs, where multiple individuals were often harvested or trapped simultaneously in sampling locations, we likely genotyped related individuals belonging to the same family group, increasing the estimation of inbreeding with subpopulation (F IS ).…”

Multiple paternity in domestic pigs under equally probable natural matings – a case study in the endangered Gochu Asturcelta pig breed

“…Our results can also be useful to further understand the mating system of the wild boar (Costa et al, 2012). There is extensive evidence of multiply sired litters in wild board that are likely to be due to ethological rather than to biological factors (Aguilera-Reyes et al, 2006;Delgado et al, 2008;Poteaux et al, 2009).…”