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Ezhovaya slopes go along the bottom as people

Fins-“legs” the rays are run by the same neurons, and genes, that of land animals.


Iron fist scat. (Photo: Andy Murch / Flickr.com)

Fish and terrestrial animals use for movement of different muscles – it is quite obvious to anyone who has ever seen a live fish. We, the animals, birds, etc moving feet, while the back remains straight and smooth (with the exception of the legless reptiles and amphibians), fish, on the contrary, floating, curving body.

It is believed that when fish came onto land, they had anew to learn to control the muscles, and the advantage of evolution has given to those who have neural circuits, allowing you to perform complex movements with fins. (Respectively, those neural circuits, which helped to wag the whole body, become irrelevant.)

However, as written in Cell researchers from new York University and their colleagues from Australia and Singapore, the neural structures necessary to work legs, fish have – at least some . Jeremy Dasen (Jeremy Dasen) and his colleagues tight studied the rays, who literally walk on the bottom using pelvic fins. All rays, as we know, move on their pectoral fins that they have a very very grown – wagging his whole body from side to side they would be uncomfortable because they are wide and flat. But ezhovaya slopes mastered another mechanism of movement: their ventral fins are also pretty much changed, becoming a kind of legs, which they move each turn (as they do, you can see here).

Researchers observed how to move embryos rays in the course of individual development. Initially, the embryos were swerving all over, then only the tail simultaneously began to move up and down their pectoral fins. Finally, when the embryos leave the eggs, they could go through one by one pelvic fins as”legs” when completely stationary ridge.

And most importantly – the time when the rays were doing, so to speak, the first step, they have formed the relevant neural circuits, such as in terrestrial animals. First, stingrays this was a special kind of neurons, second, the Hox genes, which manages the embryonic development in animals, have helped to make it a “wiring” to the muscles of the pelvic fins, and these were the same genes that share the nerves of the hands and nerves of the legs during human embryonic development.

Rays shark ancient other fish, and then it turns out that a neural mechanism to move legs and walk on land appeared about 420 million years ago, long before fish tried to jump out of the water.

We can say that land pioneers have used the old evolutionary developments; however, in the evolution of this not so rare – we already wrote about the fact that even such a complex structure like the vertebrate brain, is created on a pre-established genetic blueprints.

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