Foraging Cognition in Nonhuman Primates

Wild chimpanzees plan their breakfast time, type, and location

“…This theory is consistent with the possibility that they exhibited anticipatory planning and future-oriented reasoning (34). Chimpanzees are known to make decisions involving a single factor that affects them in future times, similar to what has been observed during goal-directed travel toward high-valued food sources in other primates (11,32,35,36). Here, the interactive effect of distance and fruit type on departure time indicate that their decisions were conditional on the combined value of multiple factors that affected them in future times (defined here as multifactorial planning).…”

“…To our knowledge, our study provides the first clear example of a future-oriented cognitive ability used in a food-scarce period within a highly competitive tropical forest environment that could enable all large-brained foragers to buffer drastic declines in food availability. We propose that large-brained foragers that need a reliable and steady intake of high-energy nutrition to maintain their large and costly brains (6,11) could gain a clear evolutionary advantage by using flexible planning that reduces indirect interspecific competition. This attribute may have been particularly important for hominoids that specialized on stationary, energy-rich, and highly ephemeral food, such as ripe fruit (14,17,24), abandoned meat carcasses, or aquatic fauna trapped in receding waters (56).…”

“…This attribute may have been particularly important for hominoids that specialized on stationary, energy-rich, and highly ephemeral food, such as ripe fruit (14,17,24), abandoned meat carcasses, or aquatic fauna trapped in receding waters (56). The proposed benefit of flexible planning skills, especially for hominids living in highly seasonal habitats like savannah, strongly encourages a more detailed focus on the temporal aspect of ecological complexity than has been done to date (1,6), and a resumed investigation of its role in theories of primate and, in particular, hominid brain size evolution (11).…”

“…These studies are built on the idea that additional neural tissue should not only be functional, but an animal must have sufficient energy to afford it (10,11). Van Woerden et al (9) found that relatively large-brained primate species showed less seasonality in their net energy intake, relative to that expected on the basis of environmental seasonality of food, than smaller-brained species.…”

Explaining brain size variation: from social to cultural brain

“…Indeed, recent primate data suggest that ecological challenges are also important. These range from the ever-changing distribution of resources, which requires orientation and spatio-temporal memory abilities and some degree of planning of range use [27,28], to technical aspects of foraging, including tool use [19,29,30], to the presence of complex anti-predator strategies [31]. However, among primates these non-social cognitive abilities are mostly found in the same species that excel in the socio-cognitive ones [26,32], and thus do not explain much additional variation.…”