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
Towering about nine feet tall — half that neck — and weighing more than 300 pounds, ostriches are the largest birds on the planet today.
But there was once an even bigger bird that roamed Madagascar before it died out about 1,000 years ago: the elephant bird.
Scientists don’t know much about these massive birds. But a study published recently in Nature communication have revealed new details about their lives – through a new analysis of fossilized eggshells.
“(Elephant birds) weigh well over 1,000 pounds … they lay an egg that’s about a foot and a half in length,” said Gifford Miller, a professor at the University of Colorado, Boulder and one of the study’s co-authors.
An elephant bird egg reconstructed from fragments in a market in southwestern Madagascar.
Gifford Miller
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Gifford Miller
An elephant bird egg reconstructed from fragments in a market in southwestern Madagascar.
Gifford Miller
The birds once had the ability to fly, Miller said. However, when they landed on Madagascar, they likely encountered few predators that evolved into flightless birds and balloons in size.
“They have to have very flexible DNA that allows them to grow quite large quite quickly. And they’re at a size where they could sort of defend themselves against any natural predator that might be out there,” Miller said.
The birds have remained somewhat of a mystery to scientists because there is not much left of them to study.
“The skeletal fossil record is quite patchy. There aren’t many complete bones,” said Alicia Grealy, a researcher with Australia’s National Science Agency and another co-author on the study.
So instead of bones, the team analyzed fossilized fragments of eggshells, which cover sand dunes and beaches across Madagascar today.
Fragments of elephant bird eggshells can be found lying on the beach or buried in sand dunes in Madagascar.
Gifford Miller
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Gifford Miller
Fragments of elephant bird eggshells can be found lying on the beach or buried in sand dunes in Madagascar.
Gifford Miller
“It was pretty exciting,” Miller said. “We had a Malagasy guide with us the whole time who could help us get around and negotiate with (locals) to get permission to be in the countryside and then wander around and find these.”
“The eggshells look like ceramics. They are so strong – they are not fragile at all.”
The shells have preserved the bird’s DNA, as well as “stable isotopes,” atomic signatures that the researchers used to study the birds’ diets.
Miller and Grealy’s team found preliminary evidence for a previously unknown lineage of the birds in northern Madagascar.
“It was a bit surprising because no skeletons have ever been found there,” Grealy said.
What happened to the elephant birds?
The researchers 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 could have turned humans into a predator that even elephant birds were unable to match.