ABSTRACT
Collective movement of social groups requires coordination between individuals. When cohesion is imperative, consensus must be reached, and specific individuals may exert disproportionate influence during decision-making. Animals living in multi-level societies, however, often split into consistent social subunits during travel, which may impact group coordination processes. We studied collective movement in the socially tolerant multi-level society of Guinea baboons (Papio papio). Using 146 group departures and 100 group progressions from 131 Guinea baboons ranging in Senegal's Niokolo-Koba National Park, we examined individual success at initiating group departures and position within progressions. Two-thirds of attempted departures were initiated by adult males and one third by adult females. Both sexes were equally successful at initiating departures (> 80% of initiations). During group progressions, bachelor males were predominantly found in front, while reproductively active 'primary' males and females were observed with similar frequency across the whole group. The pattern of collective movement in Guinea baboons was more similar to those described for baboons living in uni-level societies than to hamadryas baboons, the only other multi-level baboon species, where males initiate and decide almost all group departures. Social organization alone therefore does not determine which category of individuals influence group coordination.
Subject(s)
Behavior, Animal , Papio/physiology , Social Behavior , Animal Migration , Animals , Female , Male , SenegalABSTRACT
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
ABSTRACT
Increasingly large proportions of tropical forests are anthropogenically disturbed. Where natural regeneration is possible at all, it requires the input of plant seeds through seed dispersal from the forest matrix. Zoochorous seed dispersal - the major seed dispersal mode for woody plants in tropical forests - is particularly important for natural regeneration. In this study, covering a period of more than 20 years, we show that small New World primates, the tamarins Saguinus mystax and Leontocebus nigrifrons, increase their use of an anthropogenically disturbed area over time and disperse seeds from primary forest tree species into this area. Through monitoring the fate of seeds and through parentage analyses of seedlings of the legume Parkia panurensis from the disturbed area and candidate parents from the primary forest matrix, we show that tamarin seed dispersal is effective and contributes to the natural regeneration of the disturbed area.
