Unique beak evolved with tool use in New Caledonian crow

Date: March 15, 2016

Source: Cornell University

Cornell researchers have quantified what makes the New Caledonian crow's beak different and how it got that way. Their findings were published March 9, 2016 in the journal Scientific Reports.

It was as plain as the beak on a bird's face. Cornell ornithologist and crow expert Kevin McGowan recalls the day in the late 1990s when he first saw stuffed specimens of the New Caledonian crow.

"I remember saying to a student, 'I don't know what this bird does, but it does something different from any other corvid on Earth because its bill is so weird,'" said McGowan, project manager for distance learning in bird biology at the Cornell Lab of Ornithology.

In 2000, McGowan read a paper by Gavin Hunt, a senior research fellow at the University of Auckland, New Zealand, on tool use by these crows and he had an insight into the New Caledonian crow's unusual beak.

Now, Hunt, McGowan and a team of scientists from Japan have quantified what makes the New Caledonian crow's beak different and how it got that way. Their findings were published March 9, 2016 in the journal Scientific Reports.

"We used shape analysis and CT [computer tomography] scanning to compare the shape and structure of the New Caledonian crow's bill with some of its crow relatives and a woodpecker species with a similar foraging niche," said lead author Hunt.

"This study shows that the unique bill contributes to the birds' ability to use and probably make tools," he said. "We argue that the beak became specialized for tool manipulation once the birds began using tools, and that this enhanced tool manipulation ability may have allowed the crows to make more complex tools."

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