Christina Hansen Wheat and Lemmy, the Wolf. Credit: Peter Kaut
Many dogs are naturals when it comes to showing affection towards humans. Now, a study in the journal Ecology and Evolution reveals that wolves possess the ability to display similar behavior toward human caregivers.
Scientists at Stockholm University, Sweden, examined 10 wolves and 12 dogs in a behavioral examination designed to examine canid attachment behaviors. (Canids are members of the Canidae family of carnivorous animaturs, which includes domestic dogs, wolves, coyotes, jackals, dingoes, and other extant and extinct dog-like mammals.)
23-week-old wolves spontaneously discriminated between a familiar person and a stranger just as dogs did, and displayed more proximity seeking and affiliative behaviors toward the familiar person. Additionally, the presence of the familiar person acted as a social stress cushion for the wolves in a stressful situation.
These findings are based on a slowly growing body of evidence challenging the hypothesis that dogs had the ability to bond with humans when they were domesticated at least 15,000 years ago.
Hendrix, the wolf pup, is on the verge of genius. Credit: Christina Hansen Wheat/Stockholm University
"It was felt that there was a need to conduct a thorough investigation." Dr. Christina Hansen Wheat, PhD in Ethology from Stockholm University, Sweden, believes it is now appropriate to entertain the possibility that this variation in human-directed attachment behavior might have been a potential target for early selective pressures exerted during dog domestication.
Dr. Hansen Wheat is interested in investigating how domestication affects behavior. They raised wolf and dog puppies from the age of 10 days and placed them through various behavioral tests to create a somewhat strange and stressful situation for the animal. The idea behind the test, originally developed to assess attachment in humans, is that by fostering this unstable environment, attachment behaviors, such as proximity seeking, will be stimulated.
Björk, the wolf pup, is a picture by Christina Hansen Wheat.
In essence, what the researchers were looking for in this Strange Situation Test was whether wolves and dogs could distinguish between the familiar person and the stranger. That is, did they show more affection and spend more time greeting and in physical contact with the familiar person than the stranger? If wolves and dogs would do so equally, it would indicate that this ability does not exist exclusively in dogs.
“That is exactly what we saw,” says Dr. Hansen Wheat. “But what was perhaps even more remarkable was that when the familiar person, a hand-raiser who had been with the wolves for most of their lives, re-entered the test room, the pacing behavior stopped, indicating that the familiar person acted as a social stress buffer for the wolves.”
Dr. Hansen Wheat believes that similarities between dogs and wolves can reveal something about where our dog behavior comes from. And, while it may be a surprise to some that wolves can connect with a person in this way, she believes in retrospect it makes sense.
"Wolves showing human-directed attachment might have had a selective advantage in the early stages of dog domestication," says the author.
Dr. Hansen Wheat will continue to research and analyze the data she and her team have collected over three years in which they raised wolves and dogs in the same conditions to discover more about their behavioral differences and similarities.
Reference: "Human-directed attachment behaviour in wolves suggests a standing ancestral variation for human-dog attachment bonds," Ecology and Evolution, 20 September 2022. DOI: 10.1002/ece3.9299
This study did not receive any specific funding from government, commercial, or not-for-profit organizations.