In the vast and changing scenario of evolution, few examples are as fascinating as that of Cuvier Rallo. This bird unable to fly, originally from the homonymous atoll in the Seychelles, has experienced an extraordinary destiny: He got extinct and then “reappeared” through a process known as iterative evolution.
It all began about 136,000 years ago, when the Rallo, a flying species originally from Madagascar, reached Aldabra’s atoll. In an environment without natural predators, the need to fly became superfluous and the bird he adapted to an earth’s lifegradually losing the ability to take flight. However a dramatic climate change the island submerged under the waters of the oceanerasing all present form of life.
When, about 118,000 years ago, the sea level dropped and Aldabra Riiersi, the Rallo made his journey from the Mother Island again, the Madagascar, and settled again on the Atoll. Exactly as it happened previously, in the absence of natural threats, the species lost the ability to fly againevolving a second time in a bird unable to fly.
Is still in danger of extinction
According to scientists, this case is unique in its kind: documented of the same species that has lost the ability to fly twice during its evolutionary history. The process has been studied through The analysis of fossils collected before and after the flood of the atoll Which have shown how the bone structure of the Rallo has adapted several times to earth’s life.
The phenomenon of iterative evolution shows that, when an environment and its conditions are repeated over time, a species it can develop the same evolutionary traits more than once. This discovery not only expands our understanding of the adaptability of organisms, but also highlights the importance of fragile habitat conservation Like Aldabra.
Today, Cuvier’s Rallo is the last bird unable to fly the Indian Ocean, but his future is uncertain. Global warming and seaside level raising they threaten to submerge the atoll againputting the survival of this extraordinary species at risk. If this should happen, the Rallo could face another extinction, this time without the certainty of a new return.
