Most studies of spatial memory in primates focus on species that inhabit large home ranges and have dispersed, patchy resources. Researchers assume that primates use memory to minimize distances traveled between resources. We investigated the use of spatial memory in a group of six white-faced sakis (Pithecia pithecia) on 12.8-ha Round Island, Guri Lake, Venezuela during a period of fruit abundance. The sakis' movements were analyzed with logistic regressions, a predictive computer model and a computer model that simulates movements. We considered all the resources available to the sakis and compared observed distances to predicted distances from a computer model for foragers who know nothing about the location of resources. Surprisingly, the observed distances were four times greater than the predicted distances, suggesting that the sakis passed by a majority of the available fruit trees without feeding. The odds of visiting a food tree, however, were signiWcantly increased if the tree had been visited in the previous 3 days and had more than 100 fruit. The sakis' preferred resources were highly productive fruit trees, Capparis trees, and trees with water holes. They traveled eYciently to these sites. The sakis choice of feeding sites indicate that they combined knowledge acquired by repeatedly traveling through their home range with 'what' and 'where' information gained from individual visits to resources. Although the sakis' foraging choices increased the distance they traveled overall, choosing more valued sites allowed the group to minimize intragroup feeding competition, maintain intergroup dominance over important resources, and monitor the state of resources throughout their home range. The sakis' foraging decisions appear to have used spatial memory, elements of episodic-like memory and social and nutritional considerations.

. (2015) 'Darting primates in the eld : a review of reporting trends and a survey of practices and their eect on the primates involved.', International journal of primatology., 36 (5). pp. 894-915. Further information on publisher's website:http://dx.doi.org/10.1007/s10764-015-9862-0Publisher's copyright statement:The nal publication is available at Springer via http://dx.doi.org/10.1007/s10764-015-9862-0Additional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. AbstractCapture is one of the top ethical concerns of field primatologists, and darting is a common method of capturing primates. Little is published, however, about the safety of darting practices and conditions for the animals concerns. We conducted a literature review to examine trends in the reporting of darting methods and results, and two anonymous surveys of primatologists to gather information on darting methods and their effect on the primates involved. Among 111 papers reporting studies that darted primates, only 18 included full details of procedures, the total numbers of primates darted and the number, if any, of injuries and complications. In the surveys, 73 respondents reported on 2,092 dartings, including 44 injuries. The results show that smaller primates are more likely to be injured. 91% of seriously and fatally injured primates were arboreal, although arboreal species accounted for only 54% of the dartings. All primates who were fatally injured due to a dart hitting the abdomen or head were darted with a rifle, which were used for 45% of dartings. The presence of a veterinarian appears to reduce primate mortality in the event of injury or complications. Severe social effects of darting are not common, but include forced copulations, partner changes, and fatal attacks on infants. Lack of information about primate darting hinders refinement in methods that could improve safety. We hope this study will lead to greater sharing of information and the formation of a committee of experts in capture and immobilization to evaluate and regularly update protocols.

The papers in this special issue examine the relationship between social and ecological cognition in primates. We refer to the intersection of these two domains as socioecological cognition. Examples of socioecological cognition include socially learned predator alarm calls and socially sensitive foraging decisions. In this review we consider how primate cognition may have been shaped by the interaction of social and ecological inXuences in their evolutionary history. The ability to remember distant, out-of-sight locations is an ancient one, shared by many mammals and widespread among primates. It seems some monkeys and apes have evolved the ability to form more complex representations of resources, integrating "what-where-how much" information. This ability allowed anthropoids to live in larger, more cohesive groups by minimizing competition for limited resources between group members. As group size increased, however, competition for resources also increased, selecting for enhanced social skills. Enhanced social skills in turn made a more sophisticated relationship to the environment possible. The interaction of social and ecological inXuences created a spiraling eVect in the evolution of primate intelligence. In contrast, lemurs may not have evolved the ability to form complex representations which would allow them to consider the size and location of resources. This lack in lemur ecological cognition may restrict the size of frugivorous lemur social groups, thereby limiting the complexity of lemur social life. In this special issue, we have brought together two review papers, Wve Weld studies, and one laboratory study to investigate the interaction of social and ecological factors in relation to foraging. Our goal is to stimulate research that considers social and ecological factors acting together on cognitive evolution, rather than in isolation. Cross fertilization of experimental and observational studies from captivity and the Weld is important for increasing our understanding of this relationship.

Greater intraspecific and intrageneric variability exists in the social organization of platyrrhine primates than has previously been recognized. Although this is most marked and already recognized in the callitrichins, it also appears in many other neotropical species. One area of striking variability is the degree of troop fragmentation. Fission-fusion and cohesion are ends of a continuum of social organizations in which troop fragmentation is greatest among the former and least among the latter. Troop fragmentation appears to be a facultative adjustment to environmental, demographic, and social conditions among New World primates. A hallmark of the non-monogamous platyrrhines, and possibly of all neotropical primates, is flexibility in their social systems, and the occurrence, to a greater or lesser extent, of troop fragmentation. 0 1994 Wiley-Liss, Inc.