Mother-to-daughter transmission of hygiene in mandrills

Social animals are particularly exposed to infectious diseases. Pathogen-driven selection pressure has thus favoured the evolution of behavioural adaptations to decrease transmission risk, such as “social distancing”. Yet, such strategy might deprive individuals from valuable social interactions, generating a cost-benefit trade-off between pathogen avoidance and social opportunities. Recent studies revealed that hosts differ in the expression of these behavioural defences but the determinants driving such inter-individual variation remain poorly understood. Using 5 years of detailed behavioural and parasite data obtained on a large natural population of non-human primates, we show that, during grooming interactions, some female mandrills (Mandrillus sphinx) consistently avoid their conspecifics’ peri-anal region, where oro-faecally transmitted gastro-intestinal parasites accumulate, while others do not. This hygienic trait is further highly repeatable across the years and hygienic femal..., The table entitled \"Table_model1\" indicates for each grooming event collected during 6 study years (n = 3429): the season (\"LD\" : Long-dry, \"LR\": Long-rainy, \"I\": intermediate), the identity of the female groomer, the average population protozoan richness (during a period ranging from two weeks before to two weeks after that grooming event), and whether or not this grooming event included the peri-anal region (\"PAR\": 0/1) of the social partner.
The table entitled \"Table_model2\" gives protozoan richness of each female, each study month (n = 357 female.months), as well as female age, dominance rank (\"HR\": high-rank, \"MR\": medium-rank, \"LR\": low-rank) and proportion of risky grooming events (i.e., including groupmates' peri-anal region) for each female each study year (\"female_annual_PRG\"). \"Population monthly protozoan richness\" corresponds to the average protozoan richness in the population the corresponding month.
The table entitled \"Table_model3\" gives hygienic index for each female ea...,