New find clears Madagascar's first settlers of wiping out world's largest bird | Science

Lying about 425 kilometers off the African coast, Madagascar was long thought to be the last cornerstone of Earth to be settled. This week in Science Advances, however, researchers report that they have made their way to the island 10,500 years ago, astonishing 8 millennia more than once thought.

The discovery, by James Hansford of the Zoological Society of London, is one of the most controversial issues in the world, and is responsible for the extinction of Madagascar's unique megafauna, including giant lemurs and the world's largest bird. After 88 million years ago, then apparently centuries ago, seemingly not long after people arrived. But the blade-scarred bones from the massive elephant bird Aepyornis maximus suggest a long time to life between humans and megafauna-challenging the belief that they inevitably kill off large mammals and flightless birds when they arrive in a new land.

David Burney, a paleobiologist at the National Tropical Botanical Garden in Koloa, Hawaii, who was not involved in the study, says the results "We are in the face of everything we have been thinking about in Madagascar." The discovery, along with a few other things, is also important to him, "it is big news," he says, yes, he and others question whether it is enough to resolve the megafauna debates.

Ian Tattersall, an anthropologist at New York City's American Museum of Natural History (AMNH), says, "archaeological evidence for early human presence … is scarce at best." East Africans and Indonesians are known to have established farming settlements by 500 CE., But butchered bones of now-extinct lemurs and hippos hinted that humans were present at half-dozen centuries earlier. And on the northeast coast, archaeologists recently found small stones that appeared to date to before 2000 B.C.E., although the claim is not widely accepted.

In 2008, anthropologist Patricia Wright of the State University of New York in Stony Brook heard from a colleague who had a mantra for the sake of having had a heart attack near Ilakaka, in the south central part of the island. "I did not believe the aunt, but eventually went to visit," Wright says. With Armand Rasoamiaramanana of the University of Antananarivo, she found the "dinosaurs" were actually the remains of massive lemurs, hippos, giant tortoises, and crocodiles. The treasure also included the elephant bird, an ostrichlike creature that stood more than 350 kilograms.

The bones were stored at a nearby field center, where Hansford reviewed them in 2016. On 2-meter-long bones from the elephant bird, he noticed deep grooves, obviously made by humans butchering their prey with sharp stone tools. By measuring carbon-14, the team dated the bones to 10,500 years ago. The find "represents the earliest known evidence of human presence in Madagascar," Hansford and colleagues note.

The date is more than push back Paul Martin of the University of Arizona in the United States of America in the United States of America (United States of America) because of factors like climate change. Madagascar has since emerged as a key testing ground for the theory.

Hansford argues that his group's results, by showing that humans coexisted with megafauna for as long as 9 millennia, "eliminate the rapid extinction hypothesis or blitzkrieg for Madagascar." Only after farming populations had expanded to the island, altering the environment and increasing hunting pressure, did the creatures like the elephant bird finally go extinct, he proposed. Ross MacPhee, an anthropologist at AMNH, says the paper's conclusion is "highly consequential," because such extinctions "are frequently held up as the proof of humanity's record of destruction, past, present, and future."

Tattersall, however, says it's "premature" to make generalizations about human impact. He and Burney, a longtime advocate of the blitzkrieg theory, both note that the island of Madagascar may be a sign of a small group of humans that is so small. And the blitzkrieg hypothesis remains viable elsewhere: New Zealand's moa-another large flightless bird-went extinct 2 years after the arrival of the first Polynesians. There is no one-size-fits-all explanation for the extinctions, says Henry Wright, an archaeologist at the University of Michigan in Ann Arbor.

So far, the archaeologists searching through the ancient earths, which might shed light on the early settlers' way of life and how long they persisted on the island. Resolving the twin debates on Madagascar's settlement and the demise of its megafauna will take more digging and dating, Hansford concedes. He and his team hope to return to the bone in the near future, "now we understand the incredible significance of the site."