One of five wolf pups rescued from the edge of the Funny River wildfire in Alaska on May 27, 2014, is cared for at the veterinary facility of the Alaska Zoo in Anchorage. Photo: AP Photo/Alaska Zoo, John Gomes/MCT

Humans and other primates are more likely to catch a yawn when they are around those with whom they share "a close social bond." ###### Scientists found it is less common among those with mental conditions that cause them to have less empathy.

Yawning is also contagious for dogs. But there's a twist: They don't yawn in response to yawns from other dogs, but to yawns from people. ######

A Trip To The Zoo

A group of scientists in Japan wondered if the close connection between dogs and humans set the dogs apart from other animals. Do some other animals, aside from the primates, catch yawns too?

Dogs are "unusually skilled" at reading human behaviors, the University of Tokyo scientists noted in their study. The researchers believe "it could be possible that dogs' ability to yawn contagiously evolved with the capacity for reading human communicative signals."

###### Wolves are the closest living relatives of dogs. Like dogs, they are also "highly social," the researchers wrote.

So off they went to the Tama Zoological Park, a zoo near Tokyo. ###### There was a mother, a father and their 10 offspring (five males and five females). The researchers spent 254 hours observing the wolves over a five-month period, paying special attention to instances of yawning.

The researchers only studied certain wolf yawns. ###### When they spotted such a yawn, the researchers noted the wolf involved, the other wolves nearby, and where the wolves were looking when the yawn occurred.

Then the researchers watched the nearby wolves for the next three minutes to see if any of them yawned too. If they did, they noted the time between the initial yawn and the follow-up yawn.]]>