|Image from the Family Dog Project|
The researchers used a pointing test to measure ability to respond to human signals. This test has been used on dogs before: if a dog is given a choice of two bowls, only one of which contains food, and he can't see where the food is, will he follow a person's pointing gesture to pick the right bowl? (The bowl with no food in it is rubbed with food so the dogs can't use their noses to get the right answer.) This test has been done in the past with dogs versus human children (dogs do about the same as two year old kids on this task), dogs versus wolves (dogs generally outperform wolves, unless the wolves have a whole lot of experience with humans), and dogs versus chimpanzees, our closest primate relatives (dogs outperform chimps!).
For this study, the researchers compared hand-reared (i.e., well socialized) 8-week old dog and wolf puppies; 4 month old dog and wolf puppies; and adult dogs and wolves. They tested the animals' abilities both with "proximal" pointing (putting their finger right up to the bowl) and "distal" pointing (standing farther away and indicating the bowl) - except that, since very young puppies and wolves don't see well, they didn't test the distal pointing in the 8 week old babies. What they found:
The 8 week old puppies (dogs and wolves) had similar ability to
follow the proximal pointing gesture with the researcher's finger right
next to the bowl. However, 6 of the 13 wolf puppies tested had to be
removed from the trial because they couldn't be held on the start line
or didn't go choose a bowl. Of the 9 puppies, only one was removed for
4 month old dogs did better at distal pointing (with the researcher
standing away from the bowl and indicating it) than 4 month old wolves
did. In fact, the 4 month old wolves seemed to do no better than chance.
Adult dogs and wolves did equally well with both proximal and distal pointing.
- At all three ages, wolves needed more time to establish eye contact with the pointing human than dogs did.
It's interesting that dogs seem to develop the ability to understand a more difficult human pointing gesture at a younger age than wolves - and particularly interesting that this may have to do with the fact that wolves are not as eager to look us in the eye as dogs are. (If you don't look at someone, it's hard to follow their pointing gesture!)
So what does this mean for differences in different dog breeds? Do different dog breeds have differences in the timing of their cognitive development? Does this affect how much attention they pay to us, and perhaps how easy they are to train? We don't know, but I think this is one direction dog research needs to go.
(By the way, check out the original paper - it's open access, and has some great videos of dog and wolf puppies at the end!)
Gácsi, Márta, et al. "Explaining dog wolf differences in utilizing human pointing gestures: selection for synergistic shifts in the development of some social skills." PLoS One 4.8 (2009): e6584.
This post was originally published with slight modifications at Darwin's Dogs.