A species of bird that lived on a small group of islands in the Indian Ocean and was believed to have gone extinct more than 136,000 years ago now has a miraculous new life.
As the New York Daily News reported, the species of rails evolved into a flightless bird after migrating from Madagascar to the Indian Ocean atoll and living there over the course of many, many generations. Because the birds had no natural predators in their new home on the island of Aldabra, they eventually lost the ability to fly and became known as a new species, the Aldabra rail.
That turned out to be a big disadvantage when changing water levels brought the island underwater, flushing out the species and leading to its demise.
But in the hundreds of thousands of years since then, something even more amazing happened. The island of Aldabra eventually resurfaced, and the process that led to the evolution of the flightless bird started all over again. Over the course of roughly 20,000 years, the bird that had become extinct was back.
Researchers had seen this process play out before. Called iterative evolution, it happens when a species evolves the same exact way in separate instances. The Indian Ocean rail was highlighted in a new in the Zoological Journal of the Linnean Society.
Lead researcher Julian Hume, avian paleontologist and Research Associate at the Natural History Museum, said fossil evidence shows that the same type of rail made the journey from Madagascar to the island of Aldabra, hundreds of thousands of years apart, ending up evolving into the same species.
“Aldabra went under the sea and everything was gone,” Hume in a press release from the Natural History Museum in London. “There was an almost complete turn over in the fauna. Everything … went extinct. Yet as the Aldabra rail still lives on today, something must have happened for it to have returned.”
The find was considered a major one, researchers said. There were no other species of rails that showed that type of evolution, making it the clearest case of the process of iterative evolution found so far.
Extinct species of bird came back from the dead, scientists find https://t.co/FYUeYDwwCK
— JLM (@johnmitch59) May 12, 2019
“Only on Aldabra, which has the oldest palaeontological record of any oceanic island within the Indian Ocean region, is fossil evidence available that demonstrates the effects of changing sea levels on extinction and recolonization events,” said co-author Professor David Martill, from the School of Earth and Environmental Sciences at the University of Portsmouth.