DNA from eggshell fragments thousands of years old has provided new insights into the evolution of extinct giant birds in Madagascar.
An Australian-led team of international scientists analyzed DNA from more than 950 eggshell fragments collected across the island to better understand how the elephant bird evolved.
Elephant birds lived in Madagascar until about 1000 years ago.Credit:Bonnie Koopmans
They found that there were at least three species of the bird on the island, the largest of which was three meters high and weighed more than 500 kilograms.
QUT evolutionary biologist Professor Matthew Phillips said the team analyzed the mitochondrial DNA extracted from the eggshells, giving them a clearer picture of exactly where the different species of elephant bird fit into their family tree.
“On the southern half of the island, two species of elephant birds — the very large one and a smaller one more the size of an emu — lived together,” he said.
“And in the north we identified an ‘intermediate’ bird, more of a subspecies. So in the south they differentiate more in body size.”
The researchers also found that the different species had different diets, even though they were all herbivores.
Phillips said extraction of the DNA was a testament to the scientists’ skills, as the island’s hot climate is not conducive to preserving DNA, unlike colder parts of the world.
Lead researcher Dr Alicia Grealy, who completed work on the study at Curtin University and is now stationed at the CSIRO, said the findings provided new insights into birds that disappeared from Earth a thousand years ago.
