Check out a long piece on bonobos in The New Yorker. Now, I've read a fair amount of Frans de Waal's work, and I think the piece is making him out to be a little more PC than he is. Nevertheless, I am a bit disturbed by the fact that hasn't seen a Bonobo in the wild! I just happened to have missed that assumed that though most of his research was based on captive animals, there must have been some field research supplementing it. No. And de Waal's response it pretty lame:
Captivity can have a striking impact on animal behavior. As Craig Stanford, a primatologist at the University of Southern California, recently put it, "Stuck together, bored out of their minds--what is there to do except eat and have sex?" De Waal has argued that, even if captive bonobo behavior is somewhat skewed, it can still be usefully contrasted with the behavior of captive chimpanzees; he has even written that "only captive studies control for environmental conditions and thereby provide conclusive data on interspecific differences." Stanford's reply is that "different animals respond very differently to captivity."
Frans has to know about the problems that might occur because of a norm of reaction. Environments don't always have the same linear effect on phenotype as you vary them across different genotypes. Bonobos are complex creatures, just like humans. Just as controlled psychological studies on colleges students are important in smoking out the nature of our own species' cognitive apparatus, field work by anthropologists is also essential in documenting the extent of variation of behavior in the "wild." It see no reason why the same principle wouldn't apply to great apes, even if to a lesser extent. Update: Here's an interview with a Bonoboologist.