Paleontologists have learned to determine the sex of fossil birds konfutsiornisov bone present in the body of mature females, so it became clear that only males have beautiful "brushes" on the tail, the prints are often found in the Mesozoic deposits, according to a paper published in the journal Nature Communications.
Over the past 20 years, scientists have discovered several dozen species and protoptits ptitseyascherov that lived on Earth in the Jurassic and Cretaceous periods. The function and appearance of the first story of feathers remains unclear. Part paleontologists believe that they appeared to attract females, and others associated with the need feathers to control the temperature of the body or to plan with trees.
Group of paleontologists led by Luis Chiappe (Luis Chiappe) from the National History Museum in Los Angeles (USA) was able to explain the role of feathers, "brushes" on the tails of the ancient protoptits konfutsiornisov (Confuciusornis sanctus), learning how to determine the sex of these birds on their skeleton.
As noted by the authors, remains konfutsiornisov very common in the early Cretaceous sediments in the north-eastern China. Thanks to museums around the world have gained a solid stock of fossils, which can be divided into two conditional groups.
The first of these consists of a relatively large birds with "brushes" on the tail, and the second — from small specimens with conventional tail. Most scientists think that the first group is composed entirely of males, and the second — of the females, but it is almost impossible to prove because of the lack of visible signs of gender.
Chiappe and his colleagues noticed that the anatomy of males and females in many modern birds is much different. Researchers have tried to find the differences in the device body konfutsiornisov comparing the anatomy of the biggest konfutsiornisov with "brushes" on the tail and relatively small fish without them.
It turned out that all individuals inside the skeleton without the "brush" on the tail was present so-called The core bone, which is found only in the body of mature females. Thus, all individuals with tassels on the tail are males. Scientists believe such discovery suggests that these feathers are used to attract females.
"Like the modern chicken, females konfutsiornisa used the bone to grow calcium for egg shells. Now we know that the early birds started to breed long before they grow to the maximum. This makes them look like dinosaurs who started back in the breeding cycle youth, "- concludes Chiappe.