A flightless bird species living on a group of islands in the Indian Ocean is back from extinction after several hundred thousand years. This bird species has managed to slip from extinction for the second time. The birds on the islands died, but somehow have returned after re-evolving from an ancestral species.
This study was conducted by a combined effort of researchers from the Natural History Museum and the University of Portsmouth on a group of coral islands in the Indian Ocean. The study involved examining the fossils of the extinct species and match the similarities with the ones living on the islands.
According to the research paper published in the Zoological Journal of the Linnean Society, the bird in talks is the Aldabra Rail, living on the islands called the Aldabra atoll. The birds are known to have descended from the white-throated rail — which have the ability to fly. The white-throated rail is a native of Madagascar which flies to these islands and take residence.
The study explains, the reason behind such a huge transformation was the lack of predators on the island. The birds flew to the islands, but with no predators they didn’t need to fly and ultimately lost their ability and evolved in the birds that vanished around 136,000 years ago.
A similar event is known to have occurred when the submerged Aldabra troll re-surfaced, dating back 100,000 years. Even then, the White-throated rails are known to have colonised the islands and now they have done it again. The islands every hundred thousand years submerge and then re-surface.
Julian Hume, lead researcher, said “The fossils on the island provide irrefutable evidence that a member of the rail family colonised the islands, the closest match being from Madagascar, and became flightless on each such occasion.”
David Martill, co-author of the study, said “There is no species other than the rails that demonstrate this phenomenon so clearly. This also demonstrates the effect of changing sea-levels on the extinction and recolonisation events.”
Rails are back but there is another huge problem that is brewing — Humans have threatened 1 million species with extinction.