In a comparative study that investigates ways in which our cognitive skills and characteristics as humans have been shaped by our primate ancestry, researchers report new findings showing that human infants display the same preferences as all other great apes in their strategies for remembering where things are, but that these preferences shift as humans develop. This change in cognitive preference indicates a uniquely human developmental trajectory when compared to the cognitive development of other great apes, and it informs our general understanding of which aspects of our cognitive development have evolved within the human lineage. The findings are reported by Daniel Haun, Josep Call, Gabriele Janzen, and Stephen Levinson from the Max Planck Institutes for Evolutionary Anthropology and Psycholinguistics and appear in the September 5th issue of Current Biology, published by Cell Press.
Little is known about the inherited primate "background" of skills that underlies human cognition. Yet it is possible to trace the evolution of human cognitive abilities and tendencies by contrasting them with the skills of our nearest cousins--not just chimpanzees, but all the extant great apes--and thereby identify what we are likely to have inherited from our common ancestor.
In their new work, the researchers compared humans, chimpanzees, bonobos, gorillas, and orangutans in terms of their strategies for remembering where things are hidden. The researchers first showed that all non-human great apes and 1-year-old human infants exhibit identical preferences. This suggests that the common ancestor of all great apes enacted a similar strategy preference in employing spatial memory. The researchers then went on to examine 3-year-old human children and found that they show the reverse strategy preference. The new findings suggest that continuity exists between our species and the other great apes in the strategies we employ for spatial memory, but that this continuity is masked as human development proceeds.
The researchers include Daniel B.M. Haun of the Max Planck Institute for Psycholinguistics and the F.C. Donders Centre for Cognitive Neuroimaging in Nijmegen, The Netherlands and the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany; Josep Call of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany; Gabriele Janzen of the Max Planck Institute for Psycholinguistics and the F.C. Donders Centre for Cognitive Neuroimaging in Nijmegen, The Netherlands; Stephen C. Levinson of the Max Planck Institute for Psycholinguistics in Nijmegen, The Netherlands.
This work was supported by the Max Planck Society for the Advancement of Science.
Haun et al.: "Evolutionary Psychology of Spatial Representations in the Hominidae." Publishing in Current Biology 16, 1736-1740, September 5, 2006. DOI 10.1016/j.cub.2006.07.049. www.current-biology.com