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Chimpanzees regularly hunt and consume prey smaller than themselves. It seems therefore likely that early hominins also consumed small vertebrate meat before they started using and producing stone tools. Research has focused on cut marks and large ungulates, but there is a small body of work that has investigated the range of bone modifications produced on small prey by chimpanzee mastication that, by analogy, can be used to identify carnivory in pre‐stone tool hominins. Here, we review these works along with behavioral observations and other neo‐taphonomic research. Despite some equifinality with bone modifications produced by baboons and the fact that prey species used in experiments seldom are similar to the natural prey of chimpanzees, we suggest that traces of chimpanzee mastication are sufficiently distinct from those of other predators that they can be used to investigate mastication of vertebrate prey by early hominins. [ABSTRACT FROM AUTHOR]

Little work has considered explicitly the role of farm tenancy in influencing the uptake (or not) of diversification activities. The need to examine this link has been heightened because of the 2003 CAP reforms and the decision to tie Single Farm Payment (SFP) entitlement to the land rather than what is produced on that land. The main objective of this paper, therefore, is to examine the nature of diversification activities on tenant farms in England, which includes a consideration of how the introduction of the SFP and other CAP reforms may influence such restructuring processes. Results from a national postal survey, supported by tenant farmer/landlord interviews and a workshop, reveal high rates of farm diversification on farms with tenanted land. However, if one takes away contract/hire services the rate of diversification on tenant farms is much less. Tenant farms appear to favour more "traditional" diversification activities and the results also demonstrate an increasing need to move towards more "encultured" definitions of farm diversification. The second key finding to emerge from the research relates to the high levels of uncertainty and negativity surrounding the potential impacts of the CAP reforms, and SFP in particular, on farm business behaviour. Tenant farmers were more concerned about levels of SFP and entitlement than future investment decisions, including diversification. (Contains 8 tables.)

Develops a set of educational evaluation criteria for online continuing professional development (CPD) courses using Kolb's experiential learning cycle theory. Evaluates five courses provided by online CPD Web sites, concludes that these online courses neglect parts of the learning cycle, and suggests improvements. (Author/LRW)

Observations of chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) provide valuable comparative data for understanding the significance of conspecific killing. Two kinds of hypothesis have been proposed. Lethal violence is sometimes concluded to be the result of adaptive strategies, such that killers ultimately gain fitness benefits by increasing their access to resources such as food or mates (1-5). Alternatively, it could be a non-adaptive result of human impacts, such as habitat change or food provisioning (6-9). To discriminate between these hypotheses we compiled information from 18 chimpanzee communities and 4 bonobo communities studied over five decades. Our data include 152 killings (n = 58 observed, 41 inferred, and 53 suspected killings) by chimpanzees in 15 communities and one suspected killing by bonobos. We found that males were the most frequent attackers (92% of participants) and victims (73%); most killings (66%) involved intercommunity attacks; and attackers greatly outnumbered their victims (median 8:1 ratio). Variation in killing rates was unrelated to measures of human impacts. Our results are compatible with previously proposed adaptive explanations for killing by chimpanzees, whereas the human impact hypothesis is not supported., Substantial variation exists in rates of killing across chimpanzee study sites (2-5,10-12). The human impact and adaptive strategies hypotheses both seek to explain this variation, but have contrasting predictions, which [...]

Humans are argued to be unique in their ability and motivation to share attention with others about external entities—sharing attention for sharing’s sake. Indeed, in humans, using referential gestures declaratively to direct the attention of others toward external objects and events emerges in the first year of life. In contrast, wild great apes seldom use referential gestures, and when they do, it seems to be exclusively for imperative purposes. This apparent species difference has fueled the argument that the motivation and ability to share attention with others is a human-specific trait with important downstream consequences for the evolution of our complex cognition [M. Tomasello, Becoming Human (2019)]. Here, we report evidence of a wild ape showing a conspecific an item of interest. We provide video evidence of an adult female chimpanzee, Fiona, showing a leaf to her mother, Sutherland, in the context of leaf grooming in Kibale Forest, Uganda. We use a dataset of 84 similar leaf-grooming events to explore alternative explanations for the behavior, including food sharing and initiating dyadic grooming or playing. Our observations suggest that in highly specific social conditions, wild chimpanzees, like humans, may use referential showing gestures to direct others’ attention to objects simply for the sake of sharing. The difference between humans and our closest living relatives in this regard may be quantitative rather than qualitative, with ramifications for our understanding of the evolution of human social cognition. [ABSTRACT FROM AUTHOR]

The interaction between infant feeding and maternal lactational physiology influences female inter-birth intervals and mediates maternal reproductive trade-offs. We investigated variation in feeding development in 72 immature wild chimpanzees (Pan troglodytes schweinfurthii) at Ngogo, Kibale National Park, Uganda, and made inferences about maternal lactation over the course of infancy. We compared the percentage (%) of time that mothers nursed infants as a function of infant age and assessed how hourly rates and bout durations of nursing and foraging varied in association with differences in offspring age, sex, and maternal parity. Nursing % times, rates and durations were highest for infants ≤ 6 months old but did not change significantly from 6 months to 5 years old. Nursing continued at a decreasing rate for some 5- to 7-year-olds. Infants ≤ 6 months old foraged little. Foraging rates did not change after 1 year old, but foraging durations and the % time devoted to foraging increased with age. Independent foraging probably became a dietary requirement for infants at 1 year old, when their energy needs may have surpassed the available milk energy. Infants spent as much time foraging by the time they were 4 to 5 years old as adults did. No sex effect on infant nursing or foraging was apparent, but infants of primiparous females had higher foraging rates and spent more time foraging than the infants of multiparous females did. Although no data on milk composition were collected, these findings are consistent with a working hypothesis that like other hominoids, chimpanzee mothers maintained a fixed level of lactation effort over several years as infants increasingly supplemented their growing energy, micronutrient and hydration needs via independent foraging. Plateauing lactation may be a more widespread adaptation that allows hominoid infants time to attain the physiology and skills necessary for independent feeding, while also providing them with a steady dietary base on which they could rely consistently through infancy, and enabling mothers to maintain a fixed, predictable level of lactation effort. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2005.02.012 Byline: John C. Mitani, David P. Watts Abstract: Territorial boundary patrols are a distinctive and unique aspect of wild chimpanzee, Pan troglodytes, behaviour. Although patrolling has been frequently observed in nature and several proposed functional explanations for it exist, scant information is available regarding the proximate factors that affect this activity. We found that there is considerable temporal variation in the frequency of patrolling by chimpanzees at Ngogo, Kibale National Park, Uganda. We examined several ecological and social factors that potentially influence this variation. Results of logistic regression analyses revealed that male party size was the single best predictor of the tendency to patrol. Lethal intergroup aggression occurs in chimpanzees, and patrols are likely to be dangerous and costly. Our findings are consistent with the hypothesis that chimpanzees at Ngogo reduce these costs by patrolling together in large parties. Author Affiliation: (a) Department of Anthropology, University of Michigan (a ) Department of Anthropology, Yale University Article History: Received 9 September 2004; Revised 27 November 2004; Accepted 3 February 2005 Article Note: (miscellaneous) MS. number: A9992

Leptin is considered to act as a signal relating somatic energetic status to the reproductive system. However, the nature of that signal and its relationship with male reproductive function across nonhuman primate species are unclear. We suggest that species-specific differences in leptin physiology may be related to the degree of environmental variation and variation in the importance of energy stores for male reproduction. In order to test the role of seasonality in species differences among nonhuman primates, we compared leptin, testosterone, and body composition in male rhesus (n = 69) and pig-tailed (n = 43) macaques. Despite having larger abdominal fat deposits, the rhesus macaques did not exhibit significantly higher leptin levels (rhesus, 2.21 [+ or -] 0.43 ng/ ml; pig-tailed, 2.12 [+ or -] 0.39 ng/ml). Both species showed increases in leptin across adolescent, subadult, and adult age-groups (P = 0.036 for rhesus; P = 0.0003 for pig-tailed by ANCOVA). Testosterone was not significantly associated with leptin in either the rhesus (r = 0.039; P = 0.754) or pig-tailed (r = 0.2862; P = 0.066) samples. Comparison of leptin levels across the two species using univariate modeling procedures showed no significant age-group by abdominal fat interaction. These findings suggest little difference in leptin production between these two closely related species, despite the difference in breeding seasonality. KEY WORDS adiposity; energetics; primate mass index; Macaca mulatta; Macaca nemestrina; contest competition