Ancient eggshell fragments unlock secrets of giant bird’s life
Elephant bird eggs of extinct species greatest red bird Reconstructed from fragments of a market in southwestern Madagascar. (Photo courtesy of study co-author Gifford Miller)
Using DNA and other information extracted from ancient eggshell fragments, a team of researchers has provided a rare glimpse into the history of Madagascar’s extinct giant elephant bird. The flightless birds, thought to have disappeared about 1,000 years ago, can reach a height of 3 meters (9 feet) and weigh more than 500 kilograms, or 1,100 pounds. But despite their impressive size, scientists have had difficulty tracking their evolution and documenting the existence of different species, in part because skeletal remains do not preserve well in warm, humid climates. Surveys of some 950 eggshell fragments have now filled in some of the gaps.result just published in the magazine natural communication.
A surprising discovery: While birds may date back millions of years, the gigantic size of the largest (Epyornis maximus) Probably emerged within the last 1.4 million years, with Madagascar’s changing environment and ecosystems. The species nearly doubled in size in a very recent and very rapid time frame, the researchers said.
Recent analyzes by other researchers suggest that the birds fall into four species, one of which may be more Aepyornis is the greatest. But some have questioned these analyzes due to the lack of complete fossils. Regardless, hunting and other human activities seem to be responsible for their extinction centuries ago.
Fragmented elephant bird eggshells litter beaches and dunes along the Madagascar coastline. (Photo courtesy of study co-author Gifford Miller)
Alicia Grealy, lead author of the study, who did the study at Curtin University in Australia, said the molecules preserved in some eggshells helped the team identify a potential new subspecies living in the north of the country. They were also able to determine that different species had different diets of grasses, shrubs or succulents. In addition to DNA, the scientists also used stable isotope chemistry and eggshell size and shape to reach their conclusions.
“Despite their enormous size, Madagascar’s elephant birds are among the most mysterious and now extinct animals on the island,” said the study’s co-authors Christina Douglasand archaeologists Columbia Climate School Lamont-Doherty Earth Observatory. “Their fossils have historically been [rare] in paleontological and archaeological sites. Douglas was involved in excavations and field work to recover eggshells in southwestern Madagascar.
Grealy said: “It’s amazing to think that these thousand-year-old egg fragments can give us insights into where birds like them live, what they eat, what their ancestors might have looked like, and how they’ve evolved over the years. The eggs themselves are thought to weigh up to 10kg and take up the volume of about 150 eggs. Not even dinosaurs laid such large eggs.
The researchers say the study provides further evidence that ancient DNA in eggshells is a promising avenue for studying the evolution and extinction of other megafauna.
The paper was co-authored by about 15 other researchers from Australia and the US, as well as Sweden and the UK.
Adapted from a Curtin University press release.
