Monday, September 14, 2009
Convergence of human and dog evolution, striving to please
Topál et al. perform some fascinating comparative studies that look in dogs for a curious error noted first by Piaget, who showed that 10-month-old humans infants will persist in looking for a toy in box A, where it has been placed several times, even after having been shown that it has been moved to box B, whereas 12-month-old infants do not. This phenomenon marks a developmental milestone in human infant cognition. Adult dogs, like human infants, will persevere in searching erroneously in box A because they regard the placement of the toy by a human experimenter as a social teaching event. By contrast, wolves rapidly learn correctly to search box B. They also observed that infants are able to generalize and thus still persevere when one experimenter places the toy in box A and a second then places the toy in box B. Dogs, however, display episodic learning, and a second experimenter reduces their searching choice to chance. Topál et al. suggest that sensitivity to human communicative signals stems from convergent social evolution of the Homo and the Canis genera.