Black and grey crows genetically identical
In the West the sky belongs to the black crows, at that time both in the East dominate grey crows. On a small land in Central Europe both species are found and coexist, most likely, about 10 thousand years.
Even though the birds look quite different, the researchers noticed that they are practically identical at the genetic level.
Taxonomic status Raven black (Corvus corone) and grey Raven (Corvus cornix) was discussed long centuries, since the time Carl Linnaeus, the founder of taxonomy, said that those birds belong to different species.
A century ago Darwin called any such classification is not possible before the time, until it is accepted universally agreed definition of view. But the definition as before remains controversial. Many believe that it will be almost constantly.
As is known, both species can interbreed and create viable offspring. They do not have a reproductive barrier, which some biologists believe is needed to determine the species status. Many scientists assume that it is no more than 2 subspecies: in this situation, hooded crow called Corvus corone cornix.
Evolutionary biologist Jochen wolf (Jochen Wolf) from the Institute of Uppsala in Sweden and his colleague found that the population living in the zone crossing, unpredictable similar to the gene level: black crows even more joint with grey crows, with more than Western views.
The only difference is not very large part of the genome (less than 0.28 per cent). This section is located on chromosome 18, in the area associated with pigmentation, visual perception and hormonal regulation. It's not a coincidence, because the key differences between black and grey crows, usually, color, sexual preference (elected co-color) and social behavior, caused by hormones.
It is likely, 2 species of crow came from the joint ancestor after the glacial era pushed him to the South of Italy and the Iberian Peninsula. When the cold cover retreated, they have spread throughout Europe and began to mate again: therefore, the orientation towards divergence was interrupted and the population got an opportunity to connect.
Still, at least a large number of thousands of years crows preferred usually mate in one group, and 2 different population remained.
Now, when the mixing was relatively stable, black crows can become dominant. They are considered to be socially dominant birds and, probably, hooded crows will be more like them than Vice versa.
Scientific article about genetic similarity unlike birds was published in Science.
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