犬の社会的評価能力
Hello everyone. Welcome to SCIENSPOT. SCIENSPOT is a podcast that shines spotlight on the latest
scientific technology from Japan. Your host is REN from SCIEN-TALK.
Have you ever wondered what your dog really thinks about the people you meet, whether
they like your friends or maybe avoid certain strangers? Today we are looking at a new study
that digs right into that question. To understand this, let's first talk about something called
social evaluation. That's just a fancy way of saying judging who's nice or who's not.
In the animal world, especially for animals that live in groups, like wolves, working together
is often the best way to survive. Wolves hunt big prey as a team and everyone benefits. But
sometimes there are freer riders, individuals who take the reward without helping. That's
where social evaluation comes in. If you can tell who's a good partner and who isn't, you can
choose a better teammate. Reputation is basically a mental record of how someone usually behaves
based on what you've seen before. Animals can figure this out in two main ways, direct experience
and eavesdropping. Eavesdropping is watching how they treat others. This can be useful
because it lets you learn without the risk of a bad introduction yourself. Dogs, by the way,
descendants of wolves and were domesticated around 23,000 years ago. They've been living alongside
humans for thousands of years, relying on us for food, shelter, and friendship. So you'd think
they might be pretty good at judging human character. But the science on that has been
mixed. This new research wanted to find out if pet dogs can form an opinion about a person,
whether someone is generous or selfish, either by watching them or by interacting with them
directly. 40 pet dogs took part, split into three age groups, young, adult, and senior.
There were two situations. First, eavesdropping condition. The dog watched two people interact
with another dog. One person gave the dog food, the other person refused and turned away.
犬の評価実験
Second, direct experience condition. The dog itself interacted with the same two people,
one genius or one selfish. Researchers then checked which person the dogs approached first
and how much time they spent near each one. The result, no strong evidence that dogs preferred
the genius person in either situation. Across all ages, their choices were basically random.
Only three out of 40 dogs showed a clear preference. Two liked the genius person,
one actually preferred the selfish person. So no big pattern emerged. The researchers have a few
ideas. The two people were both women, dressed differently, but maybe the dogs still found it
hard to tell them apart. The food reward might not have been a big enough deal for a well-fed
pet dog. And pet dogs already have so many positive interactions with humans every day
that one short observation might not change their opinion. It's like us meeting someone for 30
seconds. We probably wouldn't form a strong judgment right away. Dogs might be the same.
They need repeated experiments to build a reputation of someone. Also, since the test
was outdoors, things like shade or wind might have influenced the dog's choice.
Even though the results weren't what researchers expected, this study reminded us how complex dog
behavior really is. This study was a fascinating study about how dogs evaluate humans. While the
results didn't show a clear trend, that's actually a very important finding in itself. I have a dog
at my parents' house, and I rarely believe dogs can distinguish between people. They even remember
me when I visit after a year, which makes me think they're pretty smart. But this study made me
realize something. It's difficult for dogs to judge a person's character from just one quick
interaction. On the other hand, humans can form an opinion about someone very quickly.
That's a strong sign of our own high level of social intelligence.
Future studies might look at street dogs or shelter dogs. Animals for whom choosing the
right human might be a bigger deal, or learn tests in more controlled environments.
That's all for today's science put. I share science stories like this every weekday morning
in both Japanese and English. If you enjoyed this, post your results with the hashtag science put.
I'd love to hear what you think. Thank you for listening, and see you next time.
