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How a small flightless bird ended up on an island in the middle of the ocean



An island half the size of Manhattan in the South Atlantic is so isolated that it is called an inaccessible island. On this island, and only on this island, live almost 6000 tiny shuttlecocks, which are referred to as inaccessible island tracks. But they can not fly, and the island is only a few million years old. How did the birds get there?

A new analysis could have solved the puzzle. The bird's DNA indicates that it has recently evolved from a few visitors to the island and lost its ability to fly from the forces of natural selection.

Distant Places, "study author Martin Stervander, postdoctoral researcher at the University of Oregon, told Gizmodo," It seems the birds have arrived on the island, and since they were scarcely threatened by predators, there was not much

When scientists described the bird for the first time in the 1

920s, they immediately knew that they were looking at it strangely: the inaccessible island is 3500 km from South America and 2800 km from southern Africa none of the two nearby islands less than 20 miles away.

They proposed, before the theory of plate tectonics, that the bird had run over a kind of sunken land bridge to the island. Atlantisia Recent research has suggested that the bird originates from rails in Africa.

The scientists behind the new article have other analy table tools as the bird shapes and geography. They picked up an inaccessible male islet in September 2011, took blood samples, sequenced their DNA, and compared the results to data from other tracks.

They concluded that the ancestor of the railroad was a South American bird that arrived on the island about 1.5 million years ago, and that it is more likely to be a member of the genus [19459004Lateralluswhich includes today's birds include the winged Crake, the Galapagos Crake and the similar-looking black rail, according to the journal Molecular Phylogenetics and Evolution.

That makes sense. Rails are known to fly everywhere and settle there. 53 existing or recently extinct species occur only on islands and 32 species lose their ability to fly in whole or in part. A population of the ancestors of the inaccessible island railway had probably flown east into the Atlantic and landed on the island – which was a sweet gig they no longer had to fly.

"When the railroad arrived on the inaccessible island, they were you had everything to eat because they were walking around, and there was nothing to escape from, there is no great need for flying," Stervander said. The only threat to the bird on the inaccessible island is another bird species that sometimes eats eggs and maybe some seabirds.

It's unclear why the railroad did not go to the other two islands – maybe a population tried and failed.

Stervander pointed out that more research needs to be done. The record on the tracks was incomplete, so perhaps more data indicates that the bird actually belongs to a separate genus.

And although the bird has a good life, it is still considered a vulnerable species. Flightless bird populations can easily collapse when humans bring invasive species such as cats or rats.

This paper may solve the cutest puzzle of the Southern Atlantic. However, if you plan to visit the island (which is not an easy task), make sure you do nothing to harm the birds.

[Molecular Phylogenetics and Evolution]


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