Giant eggshells reveal secrets of Madagascar’s elephant birds: NPR

An artist’s impression of elephant birds in their natural habitat, Madagascar.

Bonnie Koopmans

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Bonnie Koopmans

An artist’s impression of elephant birds in their natural habitat, Madagascar.

Bonnie Koopmans

Measuring about nine feet tall—half that neck—and weighing more than 300 pounds, the ostrich is the largest bird on the planet today.

But once upon a time there was an even bigger bird that roamed Madagascar before it went extinct nearly 1,000 years ago: the elephant bird.

Scientists don’t know much about these huge birds. but A study recently published in Nature Communications New details about their lives revealed – through a new analysis of fossilized eggshells.

“[Elephant birds] “Weighing over 1,000 pounds… they lay an egg about a foot and a half long,” said Gifford Miller, a professor at the University of Colorado, Boulder and one of the study’s co-authors.

An elephant bird’s egg reconstructed from fragments at a market in southwestern Madagascar.

Gifford Miller

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Gifford Miller

An elephant bird’s egg reconstructed from fragments at a market in southwestern Madagascar.

Gifford Miller

Miller said that the birds had the ability to fly. But when they landed in Madagascar, they likely encountered a few predators, and they evolved into flightless birds and ballooned in size.

“They must have very flexible DNA that allows them to grow fairly quickly. And they’re a size where they can kind of defend themselves from any natural predator that might be out there,” Miller said.

The birds have remained somewhat of a mystery to scientists because there isn’t much left to study.

“The skeletal fossil record is very patchy. There aren’t many complete bones,” said Alicia Greeley, an Australian National Science Agency researcher and another co-author on the study.

So instead of bones, the team analyzed fossilized pieces of eggshells, which litter sand dunes and beaches all over Madagascar today.

Fragments of elephant bird eggshells can be found lying on the beach or buried in the sand dunes of Madagascar.

Gifford Miller

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Gifford Miller

Fragments of elephant bird eggshells can be found lying on the beach or buried in the sand dunes of Madagascar.

Gifford Miller

“It was very exciting,” Miller said. “We had a Malagasy guide with us at all times who could help us get around and negotiate with him [locals] To get permission to be on Earth, and then go around and find those.”

“Eggshells look like pottery. They’re very strong—not brittle at all.”

The shells preserved the bird’s DNA, as well as “stable isotopes,” the atomic signals the researchers used to study the birds’ diet.

Miller and Greeley’s team found preliminary evidence of a previously unknown lineage of birds in northern Madagascar.

“That was kind of surprising, because no skeletons were ever found there,” Greeley said.

As for what happened to the elephant birds?

Scientists say no one knows exactly why they disappeared. But they disappeared sometime after the first humans arrived in Madagascar, suggesting that a combination of hunting and habitat change may have made humans a predator that even elephant birds were unable to match.