Some new research from Cameroon has just clobbered one of the favourite theories, that such useful tricks are seldom invented afresh in the wild, so if they spread at all, it’s through gradual “cultural” dissemination of the skill through the families and descendents of the original, inventive ape.A better title, then, might be, "Humans not as clever at figuring out chimp behavior as we once thought." Given our history of underestimating animal intelligence, this is no surprise.
A great example of this is in western Africa, where the ability of chimpanzees to crack nuts with stones was thought to be confined to forests West of the N’Zo-Sassandra River in Cote d’Ivoire. The river, uncrossable by chimpanzees, was considered to be a physical barrier beyond which the nut-cracking skill stood no chance of spreading. And all the evidence pointed that way.
Till now, that is. Bethan Morgan and Ekwoge Abwe of the Zoological Society of San Diego’s Conservation for Endangered Species facility have now put a spanner in the works by discovering chimps doing the same thing in the wild 1700 kilometres to the east, in Cameroon.
Incidentally, the abstract is here, but it's no help to a nonsubscriber.