Chimpanzee material culture: implications for human evolution

The chimpanzee (Pan troglodytes, Pongidae) among all other living species, is our closest relation, with whom we last shared a common ancestor less than five million years ago. These African apes make and use a rich and varied kit of tools. Of the primates, and even of the other Great Apes, they are the only consistent and habitual tool-users. Chimpanzees meet the criteria of working definitions of culture as originally devised for human beings in socio-cultural anthropology. They show sex differences in using tools to obtain and to process a variety of plant and animal foods. The technological gap between chimpanzees and human societies living by foraging (hunter-gatherers) is surprisingly narrow, at least for food-getting. Different communities of chimpanzees have different tool-kits, and not all of this regional and local variation can be explained by the varied physical and biotic environments in which they live. Some differences are likely customs based on non-functionally derived and symbolically encoded traditions. Chimpanzees serve as heuristic, referential models for the reconstruction of cultural evolution in apes and humans from an ancestral hominoid. However, chimpanzees are not humans, and key differences exist between them, though many of these apparent contrasts remain to be explored empirically and theoretically

Social and Cognitive Capabilities of Nonhuman Primates: Lessons from the Wild to Captivity

All anthropoid primates in nature lead highly social lives. In infancy and childhood, this is characterized by stability and familiarity for both sexes; in adulthood, either one or the other sex changes groups. The natal group provides a social network of matrilineal kinship. After sexual maturity, incest avoidance and exogamy are the rules. Significant differences exist across species and between the sexes in mating strategies. In most species, males emigrate, but in others, females do so. Male sexual behavior is based on competition between peers; females exercise choice in selecting sexual partners. Normal development of sexual behavior and maternal caretaking requires contact with adults. According to one school of thought, the selection pressures of dynamic life in groups led to the evolution of social intelligence. Such cognitive abilities are manifested in coalitions and reciprocity based on assessing the predictability of others\u27 behavior over time, i.e., on long-term relationships and short-term interactions. Another school of thought sees the evolutionary origins of cognitive capacities in the demands of subsistence. Extractive foraging requires varied techniques for the acquisition and skillful processing of foods. Long-term memory and cognitive mapping facilitate optimal budgeting of daily activities such as ranging. The absence of such social and environmental challenges may lead to pathological behavior

Humans have always been unique!

Arguments about human uniqueness apply not only to extant species but also to extinct ones, that is, the hominin predecessors of anatomically modern Homo sapiens. Thus, unique and superior are doubly relative terms, in past and present. The scope for empirical comparison faces a spectrum of difficulty, from material (e.g., artefacts) to non-material (e.g., concepts) phenomena

Practicalities of re-wilding

Re-wilding large-brained, intelligent mammals dependent on social learning to acquire survival skills is challenging. Each reintroduced species has different needs, but basic questions relating to essential aspects of successful release such as subsistence remain the same. Here I pose 12 ecologically and ethologically based questions that should be addressed (if not already done)

Real choices : a caregiver respite strategy for the state of Ohio

The purpose of Real Choices: A Caregiver Respite Strategy For The State of Ohio was to determine the feasibility of restructuring the PASSPORT program to achieve caregiver respite. We found the majority of PASSPORT consumers have at least one active caregiver. By sustaining caregiver activities and potentially keeping care at home, the cost difference between keeping the PASSPORT consumer enrolled in PASSPORT in comparison to the average cost of nursing facility care are significant. Any additional investment in Ohio s respite strategy will save the state money in the future. Based on our findings we propose a four component family-based respite strategy. The four components of the proposed PASSPORT respite strategy are: (1) Defacto Respite; (2) Defacto Respite Plus; (3) Institutionalize Respite Strategy; and (4) Real Choices. Defacto respite has already been incorporated into PASSPORT. The three additional components introduce a family-based approach to service plan development, flexibility, and consumer direction culminating in Real Choices . As we see it, Real Choices is a modest, no-strings-attached cash benefit or voucher program that is grounded in a systematic assessment of the primary caregivers needs, similar to the flexibility built into the supplemental services part of the National Family Caregiver Support Program. Cash benefits to purchase goods and services will help offset the often higher cost of other services and/or for some enabling the caregiver to continue support of the care receiver

Laterality in Termite-Fishing by Fongoli Chimpanzees: Preliminary Report

Many studies in both free-ranging and captive apes have shown that some forms of laterality of hand function occur in non-human primates1. However, true handedness (sensu McGrew and Marchant2), when most individuals show a skew in hand preference in the same direction across different tasks, seems to be restricted to humans. Other hominoids appear unlateralized in simpler tasks, such as reaching, picking up objects, and grooming3, but they show hand preference for more complex tasks, such as tool-using2, 4, 5 or elaborate food processing6, 7. Laterality in termite-fishing8 has been studied only at Gombe, and the two published data-sets are congruent. McGrew and Marchant2, 9 reported that most (27 of 36) chimpanzees showed an individualized hand preference for right or left, as did Lonsdorf and Hopkins10 (16 of 17) for termite-fishing in the same community. No other data have been published for chimpanzee communities elsewhere. This study asks if termite-fishing by Fongoli chimpanzees is lateralized, shows hand preference (individuals are lateralized, but with no populational preference for either hand), or task specialization (all or most individuals use the same hand)

Appropriate knowledge of wild chimpanzee behavior (‘know-what’) and field experimental protocols (‘know-how’) are essential prerequisites for testing the origins and spread of technological behavior. Response to “Unmotivated subjects cannot provide interpretable data and tasks with sensitive learning periods require appropriately aged subjects” by C. Tennie and J. Call

We respond to the commentary by Tennie and Call (2023) on the article by Koops et al. (2022) in Nature Human Behaviour titled ‘Field experiments find no evidence that chimpanzee nut cracking can be independently innovated.’ Koops et al. (2022) showed that chimpanzee nut cracking is not a so-called ‘latent solution.’ Chimpanzees (Pan troglodytes verus) in the Nimba Mountains (Guinea) did not crack nuts when presented with nuts and stones in ecologically valid field experiments. In their Commentary, Tennie and Call (2023) argued that the experiments were inconclusive for two reasons: 1) the chimpanzees were not motivated to treat the nuts as food, and 2) the chimpanzees were not within the appropriate ‘sensitive learning period.’ In our response, we argue that Tennie and Call (2023) incorrectly use the term ‘motivation’ to mean ‘willingness to eat the nut’, which requires existing knowledge of the edibility of the nuts. We also point out that it is unnatural and uninformative to inject nuts with honey to motivate the chimpanzees to eat them, as suggested by Tennie and Call (2023). Finally, we highlight that Koops et al. (2022) tested appropriately aged subjects (N=32 immatures). Moreover, we argue that there is no evidence to suggest that there is a strictly sensitive learning period restricted to juvenility. Finally, we emphasize the need for researchers doing experiments in captivity to visit their study species in the wild, and for field researchers to be involved in efforts to design ecologically valid experiments in captivity