evolution in action

[hitchhiker]

The Aldabra white-throated rail, a flightless bird that lives on its namesake atoll in the Indian Ocean, doesn’t look like anything special at first glance. But the small bird has big bragging rights, because it has effectively evolved into existence twice after first going extinct some 136,000 years ago.

According to a study published Wednesday in the Zoological Journal of the Linnean Society, the rail is an example of a rarely observed phenomenon called iterative evolution, in which the same ancestral lineage produces parallel offshoot species at different points in time. This means that near-identical species can pop up multiple times in different eras and locations, even if past iterations have gone extinct.

https://www.vice.com/en_us/article/vb9bpm/this-bird-went-extinct-and-then-evolved-into-existence-again

Comments

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[minoanmiss]

Isn't that title a little misleading? after a species went extinct another very similar species evolved. But do their DNA sequences match? Could they interbreed? *makes note to find study one of these days when I have time*

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[hitchhiker]

right you are. this has a better explanation:

The researchers studied fossil evidence from 100,000 years ago when the sea-levels fell during the subsequent ice age and the atoll was recolonised by flightless rails. The researchers compared the bones of a fossilised rail from before the inundation event with bones from a rail after the inundation event. They found that the wing bone showed an advanced state of flightlessness and the ankle bones showed distinct properties that it was evolving toward flightlessness.

This means that one species from Madagascar gave rise to two different species of flightless rail on Aldabra in the space of a few thousand years.

Lead researcher Dr Julian Hume, avian paleontologist and Research Associate at the Natural History Museum, said: "These unique fossils provide irrefutable evidence that a member of the rail family colonised the atoll, most likely from Madagascar, and became flightless independently on each occasion. Fossil evidence presented here is unique for rails, and epitomises the ability of these birds to successfully colonise isolated islands and evolve flightlessness on multiple occasions."

Re: *

[minoanmiss]

ahahaha my Biology degree is worth something after all!

[gingicat]

Wasn't this the premise of Jurassic Park -- forced regression, albeit with the help of fossilized DNA?

[hitchhiker]

now that you mention it, yeah! been a while since i've seen or read that.