If someone stares at you for eight seconds, you will assume he is trying to tell you something. The same thing may be true, apparently, with wolves.
A new study published in the journal PLoS One compared the facial characteristics, gazing behaviors, and sociality of 26 different canid species, from wolves to bush dogs to Arctic foxes. The researchers, based in Japan, found that animals with eyes that are easier to discern on the face are more likely to live and hunt socially. Those distinct, sharp eyes in our wolf pal up at the top of this post—the fact that you can see them so clearly, and tell so easily where they are looking, isn’t an accident.
The idea here is that certain species evolved certain facial patterns to make their eyes and thus their gaze easier for others to make out. Of the species examined in this study, 11 fell into a category where the pupil’s position within the eye as well as the eye’s position within the face are conspicuous. This includes gray wolves, three species of jackal, and the red fox, among others. Another group had a conspicuous eye position, but an inconspicuous pupil position; in other words, I can see your eyes but I have no idea where you’re looking—think of it like a person wearing sunglasses. That group includes the fennec fox and the dingo, and seven others. Finally, there was a group of six species of canid with both hard-to-see pupils and hard-to-see eyes—more mask than sunglasses. These include the raccoon dog, the bat-eared fox, and the bush dog.
So what? Well, the canids with those incredibly distinct eyes tended to be the more social animals, while those with tougher eyes to make out tended to be solo or paired animals. This was also true with regard to hunting practices—group hunters tended to have visually striking eyes and solo hunters did not. This makes logical sense: if you’re a pack chasing down a baby moose, it’s not as important to fool the moose as it might be for a fox stalking some small prey. If you’re the fox, you don’t want your lunch to know you’re looking at it.
The idea also matches up with the specific “gazing behaviors” of these animals: the ones with eyes that are easiest to see tend to stare at each other for longer, suggesting there is some sort of communication going on. Wolves in particular tend to gaze at each other for long periods, an average of 3.32 seconds in this study; two other focus species, the fennec fox and the bush dog, made eyes at each other for only 2.00 and 1.37 seconds. Wolves also engage in pointing behavior where they stare at something else for a long period—7.67 seconds on average. With these behaviors, their easily visible eyes could show their pack mates where to look.
The only two species that live in similar groups as wolves but do not have the telltale facial features are dingoes and African wild dogs. Both of those species are known to communicate in other ways, with both acoustic cues and, for African wild dogs, with motions of their white-tipped tails.
The researchers suggest this is a good place to start if we want to understand wolf and other canid communication. And of course, maybe some human behavior too: try staring at your friend’s fries next time. Chances are they’ll get the message.
- Dave Levitan | June 17 2014
Source: Ueda S, Kumagai G, Otaki Y, et al (2014). A Comparison of Facial Color Pattern and Gazing Behavior in Canid Species Suggests Gaze Communication in Gray Wolves (Canis lupus), PLoS One, 9 (6) e98217. DOI: 10.1371/journal.pone.0098217
Image: shutterstock.com, Vibe Images (top); Ueda S et al/PLoS One (middle)
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