Relatedness and genetic differentiation of white-lipped peccaries (Tayassu pecari) from the Brazilian Pantanal

Author(s)

Danilo Aqueu Rufo

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
• Defense date: 2012-09-17

Examining board members

Cristina Yumi Miyaki; Alexandra Sanches; Tatiana Teixeira Torres

• Advisor: Cristina Yumi Miyaki

Abstract

White-lipped peccaries (Tayassu pecari) are social ungulates that live in herds of usually more than 100 individuals. The aims of the present study were: 1) to evaluate whether there is any correlation between relatedness and social structure of white-lipped peccaries and 2) to re-examine whether there is significant genetic differentiation in white-lipped peccaries from two adjacent locations of the Brazilian Pantanal, based on a larger sample of individuals and of microsatellite markers. In total, 184 peccaries (53 from Fazenda Rio Negro, RN and 131 from Fazenda Santa Emilia, SE) were genotyped for 15 microsatellites. The number of alleles observed per microsatellite varied from 2 to 12, with a mean of 4.60 in RN and 5.07 in SE. Although the mean number of alleles was significantly higher in SE than in RN (p < 0.05), the mean allelic richness (4.59 in RN and 4.69 in SE) and mean observed and expected heterozygosities (0.50 and 0.53 in RN and 0.55 and 0.55 in SE, respectively) were similar in both locations (p > 0,05). The median of the coefficient of relatedness in both locations was significantly higher between individuals captured together than between individuals from different capture groups, both for the analyses including all individuals as for the analyses without the youngsters. This suggests that this result is not influenced by the possible capture of a young with its parent. Similarly, the median of the coefficient of relatedness according to gender (male vs. male, male vs. female, and female vs. female) was significantly higher within than among capture groups, including or excluding young individuals. Those results suggest that relatedness has some importance in the social structure of white-lipped peccaries. The FST between the locations was 0.017 and significantly different from zero and the DEST was 0.015. The Bayesian analysis, assuming the model of population mixture and correlated allele frequencies, showed that the most likely K was 1. When the collection site was included in the analysis, the most likely value of K was 2 and the clusters corresponded exactly to the locations of origin of the samples. Those results suggest that the white-lipped peccaries of the two sites studied comprise two populations with high levels of gene flow between them (AU)

• FAPESP's process: 10/04260-9 - Relatedness and genetic differentiation in white-lipped peccaries (Tayassu pecari) from the Brazilian Pantanal (MS)
• Grantee: Danilo Aqueu Rufo
• Support Opportunities: Scholarships in Brazil - Master