Thursday, December 23, 2010

So What Do Your Little Chimps Want for Christmas?

This Christmas, my wife and I will be giving one of our little nieces furniture for her doll house. Are we reinforcing the sexist stereotypes of our culture? Or are we rightly judging that this is her natural preference, and that it's different from her brother's preference for toys?

Why is it that little girls are more inclined to play with dolls, while little boys are more inclined to play with trucks and toy weapons? Some people say this is purely cultural, and so if the cultural practices were different, we could teach our little girls to throw away their dolls and play with trucks and guns. Others see this as showing a naturally innate difference, because girls tend to have a greater interest in caring for infants.

Remarkably, a similar nature-nurture debate must now be extended to chimpanzees. Sonya Kahlenberg and Richard Wrangham have written an article reporting a sex difference in the use of play objects among chimpanzees in Kibale National Park, Uganda, and the difference matches the human case.

Juvenile chimpanzees in this group tend to carry sticks in a way that suggests they're playing with dolls, and this is more common among females than among males. Female chimps are more likely than males to care for infants, and when a female becomes a mother, she no longer carries stick-dolls, because now she has the real thing. So carrying the stick-dolls seems to be a form of play-mothering.

But while the greater female interest in infant care has been observed in all chimpanzee groups, this pattern of play-mothering with sticks has not yet been reported for any group except those in Kibale. So this seems to be an example of chimpanzee culture. This group in Kibale has a cultural tradition of stick-doll play.

Is this nature or nurture? Or some combination of both? There seems to be some kind of social learning. But it's not that the females are learning this from their mothers, because mothers don't play with the stick-toys. So if it is socially learned, the youngsters are learning it from one another.

Here, then, is another illustration of how the complex interaction of natural inclination and social learning that we see among human beings can also be seen among our primate relatives.

Some related posts can be found here.


Troy Camplin said...

My wife and I are the kind of parents who neither encourage nor discouarge, but allow our childrens' interests to develop however they develop. It is perhaps too early to report on the 15 mo. old boy, but the 4 yr old girl is another thing entirely.

Our daughter, Melina, is obsessed with the following: dresses, shoes, dolls, cats, books, puzzles, crocodiles, dinosaurs (especially "T-saurus rex"), bugs (especially pill bugs/rollypollies), and hermit crabs (she asked for a dollhouse and hermit crabs for Christmas). Now, this may seem like a mixed bag at first. However, the dinosaurs are all friends with each other (she very much objected to my making T. rex attack the other dinosaurs) and like to have sleepovers (with the dolls, of course). Today she got after one of the hermit crabs because he was "pushing" the other one. All the dolls and animals are supposed to get along. And then there is the crocodile obsession. There are the toys, of course, but then there is the zoo. She can't wait to see the crocodiles, and she insists that they are sad until she sees them, which makes them happy. And she wants her picture taken with them of course.

In other words, she does like a few "typically boy" toys -- but she treats them all as a girl would stereotypically treat them.

Troy Camplin said...

IN addition to the hermit crabs and the doll house, Melina got two puzzles: a dinosaur puzzle and a princess puzzle. Guess which one she hugged when she opened it? :-)

Rob Schebel said...

I have two boys, 8 and 4. At my last count, we own 12 lightsabers.