We recorded the vocal repertoire and behavior of individuals from 3 groups of wild common marmosets (Callithrix jacchus) via focal sampling and ad libitum sampling in a fragment of Atlantic Rain Forest in Pernambuco, northeast Brazil. Our aims were: 1) to provide a detailed quantitative description of the vocalizations and vocal repertoire of common marmosets in the wild, and to compare the repertoire with that described from conspecific captives; 2) to investigate if differences exist in vocal repertoire between wild individuals of different ages; and 3) to explore the behavioral contexts associated with specific vocalizations in free-living Callithrix jacchus. This is the first study describing common marmoset calls in the wild and it shows that their vocal repertoire comprises 13 different calls. Though wild and captive calls were similar, differences occurred in the form of the alarm calls given for different potential predators, the tsê call, and very brief whistle. In addition, the tsee call did not occur in wild individuals and wild infants did not utter the twitter call. The age of the subjects influenced the call types present in the vocal repertoire, e.g., the loud cry was specific to infants, whereas only adults gave alarm calls. The behavior of both the caller and the potential receivers seemed to affect the frequency of wild common marmoset calls. One could predict intricate vocalization-based communications for the system based on their relatively complex social organization and densely leafed arboreal habitat. Our study confirms the prediction. Int J Primatol (

Besides its extreme climate conditions, the Caatinga (a type of tropical seasonal forest) hosts an impressive faunal and floristic biodiversity. In the last 50 years there has been a considerable increase in the number of studies in the area. Here we aimed to present a review of these studies, focusing on four main fields: vertebrate ecology, plant ecology, human ecology, and ethnobiology. Furthermore, we identify directions for future research. We hope that the present paper will help defining actions and strategies for the conservation of the biological diversity of the Caatinga.

)) argued that the 'law of brevity' (an inverse relationship between word length and frequency of use) applies not only to human language but also to vocal signalling in non-human primates, because coding efficiency is paramount in both situations. We analysed the frequency of use of signals of different duration in the vocal repertoires of two Neotropical primate species studied in the wild-the common marmoset (Callithrix jacchus) and the golden-backed uakari (Cacajao melanocephalus). The key prediction of the law of brevity was not supported in either species: although the most frequently emitted calls were relatively brief, they were not the shortest signals in the repertoire. The costs and benefits associated with signals of different duration must be appreciated to understand properly their frequency of use. Although relatively brief vocal signals may be favoured by natural selection in order to minimize energetic costs, the very briefest signals may be ambiguous, contain reduced information or be difficult to detect or locate, and may therefore be selected against. Analogies between human language and vocal communication in animals can be misleading as a basis for understanding frequency of use, because coding efficiency is not the only factor of importance in animal communication, and the costs and benefits associated with different signal durations will vary in a species-specific manner.

We report the spontaneous modification and use of sticks to fish for termites, above the ground, in wild blonde capuchins ( Cebus flavius ). These critically endangered Neotropical primates inhabit remnants of the Atlantic Forest. They used two previously undescribed techniques to enhance their termite capture success: nest tapping and stick rotation. The current ecologically based explanation for tool use in wild capuchins (i.e. terrestrial habits and bipedalism) must be viewed cautiously. Instead, remarkable manual skills linked to a varied diet seem important in promoting tool use in different contexts. The repertoire of tool-using techniques employed by wild capuchins has been expanded, highlighting the behavioural versatility in this genus.

Compassionate caretaking behaviour towards dying adult group members has been reported as being unique to humans and chimpanzees. Here we describe in detail the reaction of a wild dominant male common marmoset, a neotropical primate, to the accidental death of the dominant female of its group. The male exhibited behaviours towards the dying female that resembled those of chimpanzees and humans. The long-term relationship between the dominant pair (which lasted at least 3.5 years) and their social status in the group may have contributed to the male's behavioural response. The male prevented young individuals from approaching the dying female, behaviour previously observed in chimpanzees. The data provide an interesting insight into compassionate caretaking behaviours in New World primates as well as the pair-bond systems of common marmosets. These are rare observations, and thus their detailed descriptions are essential if we are to create a comparative and enhanced understanding of human and nonhuman primate thanatology.

Abstract:The Neotropics house two guilds of large arboreal vertebrate seed predators: parrots and the pitheciin primates. Both have diets dominated by immature fruits. The possibility of members of the Pitheciinae (genera Cacajao, Chiropotes and Pithecia) acting as occasional seed dispersers has been mooted, but not experimentally shown. We combined primate behavioural data and seed germination data from three separate field studies in the Brazilian states of Amazonas and Pará to analyse patterns of post-consumption seed survivorship for seeds discarded by three pitheciin species (Cacajao melanocephalus ouakary, Chiropotes chiropotes and Chiropotes albinasus). We then calculated the frequency of dispersal events for four species eaten by C. m. ouakary. All three primate species dropped intact seeds while feeding, and 30.7% of 674 dropped seeds germinated ex situ. Undamaged seeds from unripe and ripe samples germinated (29.3% and 42.7%, respectively), and all three primate species carried some fruits up to 20 m from the parent tree before consuming them. Potential seed-dispersal events varied from 1 (Macrolobium acaciifolium) per fruiting cycle to more than 6500 (Duroia velutina), suggesting that there are differences in dispersal potential. In summary, although they are highly specialized seed predators, these primates may also act as important dispersers for some plant species, and effective dispersal is not restricted to ripe fruits, as immature fruits removed from a tree may continue to mature and the seeds later germinate, a much-neglected aspect of dispersal ecology. The possibility that similar events occur in parrots should be experimentally investigated.

We present an ethogram for golden-backed uakaris (Cacajao melanocephalus), based on observations in the field and on a captive individual. We also provide additional observations on the ecology of the wild animals. We studied 3 free-living groups (maximum counts of 5, 15, and 26 individuals) during two wet-seasons (in the flooded igapó forest of Jaú National Park, Amazonas, Brazil. The groups lived in close proximity but never mixed, because river channels separated them. Groups showed fissionfusion behavior, subgroup sizes varied within groups, and we observed 13 different subgroup compositions. The areas used by the groups were ca. 0.82, 2.35, and 2.45 km 2 . We defined a total of 9 behavioral categories. In the wild, the amount of time allocated to the behaviors traveling and foraging/feeding differed between months, but we found no difference in the amount of time devoted to behavioral categories across 3 periods of the day, possibly as a result of the patchy and unpredictable distribution or availability of food patches. Further, the activity patterns varied among groups, perhaps as a reflection of the different group sizes and compositions and different range sizes. We recorded 34 feeding items for wild golden-backed uakaris between January and June 2008, mostly fruits and seeds. No significant variation in the number of different food types occurred across months. We recorded 6 primate species in the study areas. The uakaris neither mobbed nor Int J Primatol (2011) 32:46-68

Our study presents a detailed description of infanticide and cannibalism in a free-ranging plurally breeding group of Callithrix jacchus. The 1-month-old infant was the daughter of the dominant female, and was attacked by the group's second breeding female. Two months later, the latter gave birth to twins and appeared to have become the dominant female. These findings confirm and extend previous reports of infanticide by pregnant female marmosets, and indicate that infants of dominant breeding female, as well as those of subordinate females, are vulnerable to infanticide in plurally breeding groups. With respect to the cannibalism, this act seemed to be mainly a response to the prompt availability of food, represented by the killed infant.