Give Now  »

Noon Edition

Recognizing distant relatives

Read Transcript
Hide Transcript

Transcript

D: Yaël, last week I went to a family reunion. I could recognize lots of familiar relatives, but there were others I had never seen before.

Y: Other animals learn to recognize their relatives by familiarity too. They learn the traits of their siblings or offspring when they interact with them, and treat strangers as non-relatives.

D: But that could lead to mistakes. If you switched a bird's own chick with an unrelated chick right after hatching, before the mother became familiar with it, it would raise the unrelated chick as its own.

Y: You're right Don, and that's usually what actually happens.

D: So are there any animals that can really tell who their relatives are, even when they aren't familiar?

Y: Yes there are. In 2015, a team of European biologists published evidence that Siberian jays can distinguish relatives they've never seen before. These birds are scavengers that gather at carcasses. They share this food with relatives and chaise others away. Their territories can include immigrants that are unfamiliar and may vary in relatedness.

D: If the scientists put out food, they could see who the birds shared with and who they chased away. They would need to label the birds so they could recognize new immigrants and do DNA testing to figure out how closely related the immigrants were to the resident birds.

Y: They did all that, and showed that jays can make fine distinctions among degrees of relatedness, even when dealing with an immigrant stranger. But the jay's remarkable abilities weren't consistent. The same birds were still fooled when the scientists mixed up their chicks.

D: Recognizing relatives is hard, even for humans.

A Siberian jay with a dark head, tan body, and orange spots on its wings looks down at the chunk of wood it stands on

Biologists published evidence that Siberian jays can distinguish relatives they've never seen before. (yrjö jyske / flickr)

Have you ever been at a family reunion? What did it feel like to look around and recognize lots of familiar faces? There were probably plenty of relatives in the room you'd never seen before, too. Did you still recognize them?

Other animals learn to recognize their relatives by familiarity too. They learn the traits of their siblings or offspring when they interact with them, and treat strangers as non-relatives. But that could lead to mistakes. If you switched a bird's own chick with an unrelated chick right after hatching, before the mother became familiar with it, it would raise the unrelated chick as its own.

Tthat's usually what happens. But there are some animals that can tell who their relativs are, even when they aren't familiar.

In 2015, a team of European biologists published evidence that Siberian jays can distinguish relatives they've never seen before. These birds are scavengers that gather at carcasses. They share this food with relatives and chaise others away. Their territories can include immigrants that are unfamiliar and may vary in relatedness.

If the scientists put out food, they could see who the birds shared with and who they chased away. They would need to label the birds so they could recognize new immigrants and do DNA testing to figure out how closely related the immigrants were to the resident birds.

They did all that, and showed that jays can make fine distinctions among degrees of relatedness, even when dealing with an immigrant stranger. But the jay's remarkable abilities weren't consistent. The same birds were still fooled when the scientists mixed up their chicks.

Recognizing relatives is hard, even for humans.

Read more

Source

Support For Indiana Public Media Comes From

About A Moment of Science