Scientists have been celebrating a fossil rod from an old sea reptile that lived for 180 million years ago.
There is a thicker blubber of fat found under new marine mammal skin such as whales.
The discovery in this "sea monster" – ichthyosaur – seems to affirm that the animal was warm, so rare in reptiles.
Its skin is similar to the new whales and dolphins, after it has lost the characters of the scale of their ancestors.
The researchers say that the skin was smooth, still slightly flexible, and held evidence of the animal's pattern of hearing.
The sea-reptile was covered in darkness on the side and light on the other side. This balances the shady effects of natural light, and # 39; make it harder to see the animal.
"Ichthyosaurs are interesting because they have many common types of dolphins, but they are not closely related to those mammals that live in the sea," said co- author Mary Schweitzer, biological science professor at State University in North Carolina (NCSU).
Their likelihood suggests that ichthyosaurs and whales created strategies similar to changing sea life – an example of collaborative development.
Professor Schweitzer said: "Many of its features are similar to marine reptiles such as marine turtles, but we know from the fossil record that they gave birth to, which is associated with warm blood."
Co-author, Johan Lindgren, from Lund in Sweden, told BBC News: "A flower is found in marine marine mammals, but especially people with an adult of leather sea turtle. All these animals have a key role in having a special leather back in many subjects.
"Metabolic rates are higher than normal reptiles, and a series of measures for heat and control preservation, and these allow access to adult leather courses to cold habitats water.
"Therefore, ichthyosaurs can not control the temperature of their body at least as well as leather courts, but then it is difficult to say if they were completely endothermic (warm blood) or not. "
The researchers identified the falcones and their skin on well-preserved ichthyosaur examples with the Hauff Urweltmuseum in Germany. It was found in the Holzmaden quarry, in the south west end of the country, which has made many other fossils well maintained since the Jurassic Century.
The fossils were undergoing a detailed analysis of their microscopic structure and molecular writing.
"It is clear that both the group and the remains of members are inside," said co-author Johan Lindgren, from the University of Lund in Sweden.
"Amazingly, the fossils are well preserved that it is possible to look at individual cell scenes inside their skin."
The researchers identified microstructures similar to cells that could be likened to them, and it was considered that the liver was the organ that was inside an organ.
The fragments containing fatty acids contained in the like-like material.
"This is the first chemical evidence just for warm blood in the ichthyosaur, because blubber is a feature of empty animals," said Dr. Schweitzer.
To provide additional support for this opinion, the researchers were able to; Growing better in a modern porpoise crop, show high temperatures and stress – as it would be during a fossil process.
The "adult" porpoise battle left many features with the fossil version.
Most reptiles now have cold blood, and means that the temperature of its body is determined by the warmth of the environment. Blubber's principal role is a guardian to help with marine mammals that maintain high body temperature, despite the constant heat of ocean water.
In terms of ichthyosaur skin, the oval pattern would protect the Jurassic predators such as flying pterosaurs, invasion from above, and pliosaurs (even larger sea reptiles), which would be attacked from below.
Dr Lindgren said: "With the close proximity of pig cells, and that occur in both epidermis and dermis, we suggest that skin ichthyosaurs dark dark (dark) dorsal, which can also be seen in many whales that grow Different dialects (such as ichthyosaurs) and enter into artificial, arctic sections (like ichthyosaurs).
"The dark (dark) wins would benefit UV protection as ichthyosaurs while it was at the seabed, but it might also help ichthyosaurs as the case in the leather turtle. "
It would be to lose the screen and smooth skin; It also moved to move ichthyosaurs to make it easier underwater.
Johan Lindgren said that the flexible skin meant that the symbol had to be fossil as soon as it was; The organic molecule was absorbed within the mineral component of the fossil.
"Bog tools, such as skin, so misleading (easily broken down) are considered to have the same way in which they can survive by replacing full miners. , as it appears, when these mines are removed, some of the original legends are still, "explained Dr. Lindgren.
The results are published in Nature magazine.
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