Forget the funky chicken—the blue-capped cordon bleu prefers a tap dance to attract mates, a new study says.
Scientists already knew males of these blue-and-tan African finches bob and sing as part of their courtship display. So did males of two closely related species, the red-cheeked cordon-bleu and the blue-breasted cordon-bleu. But new high-speed video shows behavior that was long hidden to humans: Both males and female cordon bleus actually perform a type of tap dance. (Also see "Dancing Animals Help Tell Us Why Music Evolved.")
“You cannot see this with the naked eye because it’s so rapid,” said study co-author Masayo Soma of Hokkaido University in Japan.
What's more, the cordon bleus, these Fred Astaires of the bird world, seem to be unique: “No other species we know of has this tap dancing behavior.”
While we may struggle to walk and chew gum at the same time, many bird species can put on elaborate song-and-dance shows to attract partners. (See National Geographic's amazing songbird pictures.)
In many bird species, a male mates with more than one female. This means that females have to be choosier, since a male will have many chances to pass on his genes, whereas a female might only get one shot.
As a result, it's usually males strut their stuff in a bid to snag a female.
Blue-capped cordon bleus, however, are monogamous, which means that both males and females are notoriously picky about their mates. (Also see "Birds Can Dance, Experts [and Zany Videos] Reveal.")
Both male and female blue-capped cordon bleus court by holding a piece of nesting material in their beak, and then bobbing up and down and singing.
Since courtship in both genders is so rare among birds, the scientists wanted to know more.
It's hard to record their behavior in the wild, so she turned to a colony of captive cordon bleus in the lab of Manfred Gahr at the Max Planck Institute for Ornithology in Germany.
The researchers set up both normal- and high-speed video cameras in a large cage. They then placed a randomly selected male and female pair in the cage, switched on the cameras, and waited. And waited. Frequently, the birds didn’t court each other at all.
But some did, eventually. Of those, the normal-speed video revealed the bobbing and singing routine scientists already knew about. The high-speed camera, unmasked their movements: During the display, both birds would dance about three steps in less time than it takes us to blink, according to the study, published November 19 in Scientific Reports.
Sounds Like a Winner
Soma calls it tap dancing for a reason beyond the fancy footwork: She believes that the sound produced by the stepping provides more information about the dancer's fitness. (See "Birds "Walk" on Water to Impress Mates—Here's How They Do It.")
For instance, a bird that can keep dancing—and producing tapping noises—for several minutes signals that it's in good health.
“This study is part of an exciting shift," says Anastasia Dalziell, a postdoctoral student at the Cornell Ornithology Lab who was not involved in the research.
"Scientists had focused a lot on song, and now they’re starting to study visual display," Dalziell says. "Their work is very detailed, and it’s something researchers hadn’t examined before."
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