Photo via Tambako/Flickr
Does the lonesome wolf howl at the moon for the same reason a dog cries when its master leaves it home alone? Tracing the roots of canine communication is difficult, but new research suggests that wolves don't simply cry out in response to their environment. Instead, they're capable of shaping their communication to fit their own social structure.
In other words, a new study in Current Biology found that wolves factor in who they're talking to in how they shape their communication, similarly to how you may communicate with your boss differently than one of your friends.
"Our results suggest the social relationship can explain more of the variation we see in howling behavior than the emotional state of the wolf," said co-author Friederike Range of the Messerli Research Institute at the University of Veterinary Medicine Vienna in a release. "This suggests that wolves, to a certain extent, may be able to use their vocalizations in a flexible way."
The study focused on a pair of wolf packs living at Austria's Wolf Science Center, and aimed to answer a simple question: Is a wolf's howling simply a stress response—perhaps to a pack member leaving—or are they driven by more than simple emotion?
This is important area of research because while the purpose of canine communication has been well-studied, especially in highly-cooperative species like hyenas, the authors note that "the proximate mechanisms driving call production remain surprisingly unclear."
At the wolf center, handlers take wolves from the two packs on site out for individual leashed walks (sounds like a fun job, doesn't it?), during which the remaining pack members have been observed to always howl. This makes sense, as it has been previously observed that wolves use their howls to reunite their pack over long distances.
To measure if either emotion or social structure was a factor in that response, the researchers measured the levels of the stress hormone cortisol in the wolves left behind and compared it to their observed ranks and relationship quality with other members of their packs. For controls, the research team conducted the same observations on the wolves when their packs were intact.
It's in German, but this Der Spiegel video offers a cool look at the Wolf Science Center.
The team found that while stress levels were higher in experimental groups—losing a pack member stresses the wolves out—the frequency of howling did not correlate tightly with their cortisol levels. At the same time, the researchers found that wolves howl more when they have a higher-quality relationship with the 'lost' individual. In other words, the wolves howl more if they care more about the individual that disappeared.
"Since the amount of howling of individual wolves was mediated by their relationship to the separated animals, the wolves seem to have some volutary control of their calling, so it is not just a reaction to a stimuli but dependent on the social factors involved," Range said in an email.
What's truly fascinating about this finding is not that wolves use their howls to keep the pack together, as it's an intuitive expectation. It's that wolves appear to be able to modulate their responses based on the strength of a bond with another individual. You'd likely put more effort into a search for a lost friend than an acquaintance, and it appears that, at least to some degree, wolves do too.
This pushes back against the notion that animal communication is limited to simple cause-and-effect responses to stimuli—that a dog barks because something triggered the bark, and that it's beyond its cognitive abilities to control its response. But the wealth of cognition research in recent decades has shown that, for many species, communication is more nuanced.
"I think this applies to animal communication in general: it might be more advanced [and more flexible] than many people thought," Range said.
Range explained that the study didn't lend any evidence that wolves can "talk," as it focused on the cause of communication, not the intended use. But it is quite interesting that wolves' communication is mediated, at least to a degree, by their perception of social structures and values, which is a higher-level cognitive concept than simply barking when you get jabbed with a stick.
It's a finding that's been replicated more and more across the spectrum of highly intelligent species. The authors note that chimpanzees' food calls were once thought to be simply a response to hunger, but recent research suggests that chimps' dinner calls are also influenced by who's around to hear the invite.
It might be a bit of a stretch to say that social influence on communication is evidence that animals have friends, at least in the human sense. Yet the trends in cognition research do suggest that, like some of us humans, some animals know how to tailor their chatter to their audience.