Tuesday, June 9, 2009
I think it's fair to say that anyone who knows me well has heard me bitch about the capuchins we used to house in the lab. (Well, okay, there are probably those of you who know me well but I refrain from discussing graduate school with...mostly because I would hate to scare you...). For those of you unfamiliar with my woes, suffice it to say that capuchins are a) very smart little bastards, b) amazingly good at finding obscure parts of the wall to hang onto and jump from, and c) incredible crack-shots with monkey urine. My scalp still burns thinking about c. Their only saving grace is their cuteness. And we all know that I am a sucker for cute. And primates in general. Especially their feet. But I digress...
Anyway, it turns out that not only will capuchins pee on your head with only the slightest provocation, they're also lying, cheating little bastards. Or so says Brandon Wheeler (who I am happy to say I know...if only because he makes fun of me and screams obscenities at me from his bike on a regular basis). At Stony Brook, we like to joke about the stuffed carnivores that he used to elicit actual warning calls from the capuchins he was studying, but then again, how are you supposed to assert that they're shouting "Holy shit! BIG F'ING CAT!" if you have no idea what capuchins shout when there is a BIG F'ING CAT! present?
For those of you playing the home game, what Brandon's research found was that low ranking capuchins will often sound alarm calls for no good reason other than to scare high ranking group members away from a food source long enough for them (the low ranking member) to gank some. How do you demonstrate something like this, you may ask? How on earth are we supposed to know they're being deceptive, not being fluent in capuchin and all? Well, first you have to figure out whether the monkeys actually have specific calls for predators, or whether they are just squeaking gibberish. To do this, different models of capuchin predators were placed in the groups daily paths. When a group member gave a call, the call was recorded and the context was noted. Once it was clear that specific calls were given in the presence of certain predators (to the exclusion of just squeaking for the hell of it - there had to be a specific predator present and the call had to elicit evasive behaviors from the rest of the group), the deceptive use of these calls could be examined. As it turns out, low ranking members of capuchin groups will routinely give predator alarm calls when a limited food source is present. High ranking members get to eat first, and, as such, are usually already gorging themselves. When the alarm call is given, they freak out and run, leaving the food unguarded for the low ranking members to help themselves to.
Why on earth is this interesting? Mostly because it's comforting to know that humans are not the only primate who will lie, steal, and cheat their way through life. Lord knows we always need new excuses to justify acting like assholes. But also, because it gives us some insight into the cognitive development of other primates. It's unclear from the current research whether the monkeys lie intentionally, understanding that they are being deceptive, or if they simply associate the call with a food reward. Further research will undoubtedly focus on teasing out this difference, and either way it provides some insight into our own behavior. Is deceptiveness adaptive? Do deceptive monkeys have a higher survival rate than those who never give false alarm calls? Is this behavior genetic or learned? Are we indeed heading toward socialism, or just away from social Darwinism? Lots of important and interesting questions remain to be answered. I almost wish I was a monkey chaser rather than a gooey-jar-monkey examiner!