Ancient Eggshell Fragments Crack Giant Elephant Bird’s Life Secrets
An elephant bird egg of the extinct species Aepyornis maximus reconstructed from fragments in a southwest Madagascar market. (Photo by study coauthor Gifford Miller)
A team of researchers has used DNA and other information extracted from ancient eggshell fragments to offer a rare glimpse into the history of Madagascar’s extinct giant elephant birds. The flightless birds, that are thought to have disappeared about 1,000 years ago, reached three meters (9 feet) in height and weighed greater than 500 kilograms, or 1,100 kilos. But despite their spectacular size, scientists have had a tough time tracing their evolution and documenting the existence of various species, partially due to poor preservation of skeletal stays in the nice and cozy, humid climate. Investigations of some 950 eggshell fragments have now filled in a few of the picture. The outcomes were just published within the journal Nature Communications.
One surprising finding: While the birds probably trace back many hundreds of thousands of years, the large size of the biggest ones (Aepyornis maximus) likely arose inside just the last 1.4 million years, alongside the changing environment and ecosystem in Madagascar. This species nearly doubled in size over a really rapid and up to date time-frame, say the researchers.
Recent analyses by other researchers suggest the birds were divided into 4 species, including one which will have been even greater than Aepyornis maximus. But some have called these analyses into query as a consequence of an absence of intact fossils. In any case, hunting and other human activities appear to be the reason for their demise centuries ago.
Large concentrations of fragmented elephant bird eggshells might be found scattered across beaches and sand dunes along the coastline of Madagascar. (Photo by study coauthor Gifford Miller)
Lead creator Alicia Grealy, who accomplished the research at Australia’s Curtin University, said that molecules preserved in some eggshells helped the team discover a potentially recent sub-species that lived within the north of the country. They were also in a position to determine that different species had distinct diets of grass, shrubs or succulents. Along with DNA, the scientists used stable isotope chemistry and the scale and shape of eggshells to succeed in their conclusions.
“Despite their towering size, Madagascar’s elephant birds are one in every of the island’s most mysterious now-extinct animals,” said study coauthor Kristina Douglass, and archaeologist on the Columbia Climate School’s Lamont-Doherty Earth Observatory. “Their fossils have historically been [rare] at paleontological and archaeological sites.” Douglass participated in excavations and fieldwork to get better the eggshells in southwest Madagascar.
“It’s amazing to think that these thousand-year-old egg fragments may give us insight as to where elephant birds lived, what they ate, how their ancestors may need looked, and the way they evolved through the years,” said Grealy. The eggs themselves are thought to have weighed as much as 10 kilograms, and occupied the quantity of about 150 chicken eggs. Even dinosaurs didn’t lay eggs this big.
The study reinforces how ancient DNA from eggshells is a promising avenue for studying the evolution and extinction of other giant animals, say the researchers.
The paper was coauthored by some 15 other researchers from Australia and america, in addition to from Sweden and the UK.
Adapted from a press release by Curtin University.
