Animal Conformists

摘要

More than 60 years ago, Kinji Iman-ishi speculated that if animals can learn from each other, they will inevitably develop different behaviors in different groups, resulting in "cultural" variation within the same species (1,2). It was a simple proposal, but so far ahead of its time that few Western scientists paid attention. Only in the past few decades has animal culture taken off as a topic of research. Two reports in this issue give hints of the adaptive value of animal culture. On page 485, Allen et al. (3) show that the best explanation for the spreading of a new hunting technique among humpback whales (Megaptera novaeangliae) is that they learn from each other, and on page 483, van de Waal et al. (4) report an innovative field experiment that manipulated the food preferences of wild vervet monkeys (Chlorocebus aethiops) to give them an opportunity for social learning. The early debate about animal culture focused on the mechanism of behavioral transmission. Do animals learn from each other in the same way as humans do? If they copy the behavior of others, does this reflect "true" imitation, that is, do they understand the other's goals and methods? Apes were said to lack imitative capacities because they failed to imitate human models (5). But of course, human models belong to a different species. We now know that apes learn from each other in ways that meet all the requirements of true imitation (6—8).