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A capacity for constructing new tools, or using old tools in new ways, to solve novel problems is a core feature of what it means to be human. Yet current evidence suggests that young children are surprisingly poor at innovating tools. However, all studies of tool innovation to date have been conducted with children from comparatively privileged Western backgrounds. This raises questions as to whether or not previously documented tool innovation failure is culturally and economically specific. In the current study, thus, we explored the innovation capacities of children from Westernized urban backgrounds and from remote communities of South African Bushmen. Consistent with past research, we found tool innovation to occur at extremely low rates and that cultural background had no bearing on this. The current study is the first to empirically test tool innovation in children from non-Western backgrounds, with our data being consistent with the view that despite its key role in human evolution, a capacity for innovation in tool making remains remarkably undeveloped during early childhood. [ABSTRACT FROM AUTHOR]

Background: Crows and ravens (Passeriformes: Corvus) are large-brained birds with enhanced cognitive abilities relative to other birds. They are among the few non-hominid organisms on Earth to be considered intelligent and well-known examples exist of several crow species having evolved innovative strategies and even use of tools in their search for food. The 40 Corvus species have also been successful dispersers and are distributed on most continents and in remote archipelagos. Results: This study presents the first molecular phylogeny including all species and a number of subspecies within the genus Corvus. We date the phylogeny and determine ancestral areas to investigate historical biogeographical patterns of the crows. Additionally, we use data on brain size and a large database on innovative behaviour and tool use to test whether brain size (i) explains innovative behaviour and success in applying tools when foraging and (ii) has some correlative role in the success of colonization of islands. Our results demonstrate that crows originated in the Palaearctic in the Miocene from where they dispersed to North America and the Caribbean, Africa and Australasia. We find that relative brain size alone does not explain tool use, innovative feeding strategies and dispersal success within crows. Conclusions: Our study supports monophyly of the genus Corvus and further demonstrates the direction and timing of colonization from the area of origin in the Palaearctic to other continents and archipelagos. The Caribbean was probably colonized from North America, although some North American ancestor may have gone extinct, and the Pacific was colonized multiple times from Asia and Australia. We did not find a correlation between relative brain size, tool use, innovative feeding strategies and dispersal success. Hence, we propose that all crows and ravens have relatively large brains compared to other birds and thus the potential to be innovative if conditions and circumstances are right. [ABSTRACT FROM AUTHOR]

Nut cracking is restricted to communities of wild chimpanzees living in West Africa, suggesting it is an example of a socially transmitted tradition. Detailed study of the acquisition of nut cracking in wild chimpanzees is consistent with this conclusion. However, only 2, small-scale experiments have been carried out in captivity to explore the role of social transmission in the acquisition of this behavior. The study presented here does this with a comparatively larger, statistically viable sample of II sanctuary-living chimpanzees (Pan troglodytes schweinfurthii), permitting both between- and within-subjects experimental manipulations. Results confirmed that nut cracking can be acquired in a matter of days by social learning, but only in chimpanzees 3 to 4 years old and older. Direct comparisons are made with a study carried out in the wild, revealing striking similarities in developmental profiles. [ABSTRACT FROM AUTHOR]

A trademark of Homo sapiens is the enormous variation in behavioral patterns across populations. Insight into the development of human cultures can be aided by studies on communities of Pan across Africa that display unique combinations of social behavior and elementary technology. Only cross-population comparisons can reveal whether the diversity reflects differential genetics, environmental constraints, or is a cultural variant. However, the recently recognized and most endangered subspecies, Pan troglodytes vellerosus, remains completely unstudied in this respect. We report first evidence from a new long-term study of Nigerian chimpanzees at Gashaka. Their dietary composition is highly varied and they have to cope with high concentrations of antifeedant defenses of plants against consumption. Gashaka chimpanzees use a varied tool kit for extractive foraging. For example, they harvest insects throughout the year, via digging sticks and probes, to obtain honey from stingless-bee and honeybee nests, dipping wands to prey on army ants, and fishing rods to eat arboreal ants. Tools appeared to be custom-made with a considerable degree of standardization in length, diameter, and preferential use of distal ends. Moreover, compared to the rainy season, tools were longer during the dry season when insects retreat further into their nests. Many of the expressions of subsistence technology seem to be environmentally constrained. Most notably, the absence of termite-eating could reflect a low abundance of mounds. Other traits may represent cultural variation. For example, the chimpanzees did not hammer open 2 types of hard-shelled nuts with tools, unlike what occurs elsewhere in West Africa. The prevalence of elementary technology may indicate that the material culture of Gashaka chimpanzees is most related to core cultural tendencies of Central African populations. [ABSTRACT FROM AUTHOR]

We present a detailed study of ant-dipping among the wild chimpanzees (Pan troglodytes verus ) of Bossou, in southeastern Guinea, West Africa. Observations suggest a strong influence of prey (Dorylus spp.) characteristics, including aggressiveness and/or gregariousness, on tool length and technique employed by the chimpanzees. Bossou chimpanzees exhibit two ant-dipping techniques: 1) direct mouthing, and 2) pull-through. In addition, they were observed dipping for several species of Dorylus ants, classed into two categories: Red and Black. Tool length was longer when dipping in higher-risk contexts, i.e., at the ants' nest site or on Black ants. The pull-through technique was almost exclusively associated with dipping at the nest site. This latter technique was associated with tools over 50cm long, whereas direct mouthing was the only technique observed with tools <50cm long. Our experimental findings, together with our observations on the behavior of the chimpanzees, suggest that at the nest, the pull-through technique was a more efficient technique than direct mouthing. We review our results in the context of ant-dipping observed at two other long-term chimpanzee study sites, i.e., Gombe (Tanzania) and Taï (Côte d'Ivoire), where differences in tool length, technique used, and focal Dorylus ant species have been reported. Finally, we urge similar detailed studies of this tool-use behavior in both Gombe and Taï to shed further light upon our results and their implications. Am. J. Primatol. 58:133–148, 2002. © 2002 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]