Some Songbirds Have Brains Specially Designed to Find Mates for Life
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Science
Some Songbirds Have Brains Specially Designed to Find Mates for Life
By JOANNA KLEIN FEB. 13, 2018
If Cupid wanted to make two songbirds fall in love, he’d have better luck aiming at their brains. That’s because songbirds, which form lifelong mating pairs, have brain systems perfectly tuned to fit together.
While you sort through the messages of admirers, deciding who to make your Valentine, consider finches.
Young males in this family of feathered crooners learn the song of their father, perfect it and perform it as adults to attract a lifelong mate. It’s loud, elaborate and precise. With their songs they say “chirp, chirp — my brain is healthy, and my body is strong. That’s something you’re into, right?”
A female finch also learns the songs of her father from a young age, but she doesn’t perform. She’s the critic. She analyzes every detail of a potential mate’s song, compares it to her father’s example and decides if this performer is one she’d like to keep around. If she detects a song is too simple or off in any way, she’ll have nothing to do with its performer. She’s very picky, as she should be, because the mate she chooses will help raise their young — till death do they part.
Over the past decade, researchers looking into the chickpea-sized brains of finches have discovered that each sex uses what’s called its sound control system to convert sound waves to social messages and then use them to find mates, kind of how humans use vocal sounds to communicate. And while these systems are well-developed and finely tuned in both sexes of songbirds, the wiring is different.
“The biggest difference between male and female brains of the same species is found in songbirds,” said Sarah Woolley, a neuroscientist who studies finches at Columbia University’s Zuckerman Institute.
Dr. Woolley’s lab has been looking into the acoustic systems of zebra, bengalese and long-tailed finches to see how their brains take in and process sounds — learning, performing and analyzing different parts of them to make sense of songs.
A male’s system is designed to recognize the songs of other males and copy his father’s. If he doesn’t learn, perfect and memorize his father’s song within the first 90 days of life, when his brain is especially malleable, he never will. He still sings, but “he sings a disaster,” said Dr. Woolley. “And the females want nothing to do with him.”
When a female’s brain is young and malleable, she tunes into her father’s song, memorizes it and then stores it as a template for evaluating a mate’s song later. This example reminds her that she didn’t die, and her father helped ensure that. Perhaps something similar will work for her offspring.
Females tend to prefer elaborate songs with more syllables.
How well the birds learn depends on a genetic predisposition to tune into sounds specific to their species. But experience is important too. Because social relationships are so powerful, a baby bird reared by the wrong species, Dr. Woolley has found, can learn the wrong species’ song even if its biological father’s song is audible.
“The magic of the songbird is that vocal learning is incredibly rare to find in animals,” said Dr. Woolley. “No ape can do it (except the human), no monkey can do it, and no rodent can do it.” And she believes that by understanding more about how songbirds use their brains to make sense of sound, she can learn more about how humans use theirs to develop a spoken language early to communicate later in life.
For songbirds that form bonds with members of the same sex for life, songs, though still important message bearers, may be less important for finding a match.
And although some humans may be less interested in words than other aspects like looks, scent, youth, money, power or whatever we find attractive in a partner, birdsongs remind us that good communication, in any pair, makes love possible. “The way that people fall in love, is talking to each other,” Dr. Woolley said.