Pontes para o futuro: Interações de mães e filhotes de muriqui do norte (Brachyteles hypoxanthus)

Abstract

Parental care in northern muriqui (Brachyteles hypoxanthus) is maternal exclusivity, the mother is responsible for protection, feeding, locomotion and for introducing the children to the social environment. The help with locomotion occurs in two moments, in the first moment the mother carries the infant during the group displacements and in the second moment the mother helps in an opportunistic way, being called bridges. In this type of care, the mothers bring the ends of the trees closer together, forming a bridge, so that their young can pass over their bodies, crossing to the next tree. Bridges are used for crossings when the treetops are far away and passage between branches would be difficult for a small animal. The aim of the project was to characterize the use of bridge aids and the differences between males and females of primates of the species Brachyteles hypoxanthus. The collection method was through Ad libitum, accompanying the Matão group in the Feliciano Miguel Abdala Natural Heritage Private Reserve (RPPN-FMA), located in the municipality of Caratinga, Minas Gerais. The analyzes were carried out using the statistical tests GLM (Generalized Linear Model), Kruskal-Wallis Test, post-hoc and Mann Whitney Test. The effect of the sex and age variables was tested by the bridge rate (number of bridges registered by individuals, divided by the number of individual scans). To compare the age categories and the difference between males and females through the bridging rate variable, the age classes were separated every six months, with categories 0-6, 7-12, 13-18, 19-24, 25-30, 31 36 months of age, an average rate was calculated for each individual in each age class. All analyzes were performed in the R software (R Development Core Team 2023). In general, the period of greatest use of bridges occurs during the second year of life (15 to 30 months). While males initiate assistance earlier than females, females use the bridges for a longer period. It was possible to understand through the analyzes the period of greater use of bridge aid and the difference between males and females. These results seem to be related to changes in individuals' social and eating behavior. This study allows us to understand up to what age the infant needs the mother's help to move, which allows us to set up management strategies between the groups