According to modern paleontologists, giant ancient reptiles began to explore the watery element at the end of the Permian period of his life on earth.Scientists say that the ancient reptiles throughout his life always came back in the water.The reason for that - an abundance of the underwater food and, of course, safety.
in the seas and oceans
curious that life in the seas and oceans is not required of ancient reptiles a fundamental restructuring of the body: one has only to recall the modern reptiles that live in the water, but it is a land with a look.For example, it's crocodiles and marine iguanas.
should be noted that the movement of the dinosaurs and the food in the water - it's energy costs account for only a quarter of the costs required for their transportation and supply directly to the land!Especially easy to back into the water so-called primitive dinosaurs - a dead-end branch of evolution.But that's another story.
first flying dinosaurs - who are they?
Scientists believe that the first true dinosaurs were watersports Permian Mesosaur representing a subclass anapsid.Already after them into the water return representatives of the so-called primitive Diapsid: tangozavry, hovazavrusy and klaudiozavry.
All of them belonged to the order eozuhy and reaches a length of only 50 cm. Only in the middle of the Triassic dinosaurs floating "up" to the two-meter lengths, becoming, finally, serious and even dangerous reptiles.
Externally they resembled today newts from the class of amphibians: the water eozuhii had a long tail, flattened laterally, and a comb passing back through the body.The Triassic in the world there are not more than 5 groups of aquatic reptiles.One of them we just looked - it eozuhii water.Consider the details and other types of flying dinosaurs.
Plakodonty
Externally, these reptiles resemble small long-tailed seals.Their length was less than 1.5 m. The body was streamlined plakodontov and spindle-shaped.Small head, short legs.Methods swimming dinosaurs belonging to the group plakodontov, not very diverse, reptiles simply pulled along the body of his awkward short legs and floated like little torpedoes.
As mentioned above, the whole truth about dinosaurs-plakodontah, like many other aquatic reptiles, shrouded in darkness and mystery.Scientists are inclined to believe that this - the descendants of some ancient anapsid.However, a century plakodontov was short - these creatures originated in the early Triassic, but by its end completely extinct.
nothosaurus
This is one floating dinosaurs that lived in the Triassic era.Their size reaches 4 m in length, but the vast majority of them were still considerably less.Predatory reptiles had a streamlined body, short tail, a rather flexible neck, equal to the length of their body.
They had a small head with a mouth armed with sharp teeth.These create moving water by means of repetitive movements tail providing a driving force, as well as through its webbed feet.
nothosaurus If need arises, they can easily climbs to the beach and basking in the sun.Scientists believe that the predators were Crossopterygii ancient fish species.It is interesting that in the second half of the Triassic period, these beings have created a separate branch of the now famous aquatic predators - plesiosaurs.Themselves nothosaurus extinct by the end of the Triassic.
Tallatozavry
This group resembles the above nothosaurus only neck was shorter and the head is larger.Methods swimming dinosaurs in this group can not be called unique: they are not used to paddling their legs, just pull them along the body as plakodonty.
scientists are inclined to believe that there have been these creatures from some ancient and primitive anapsid even more ancient than the previously mentioned water eozuhii.They died out by the end of the Triassic, as nothosaurus.No descendants have left behind.
ichthyosaurs
This latter group, which was represented by the most famous all over the world flying dinosaurs - ichthyosaurs.Ichthyosaurs better than any other dinosaurs were adapted to life and habitation in the seas and oceans.It is known that these predators - descendants Diapsid and what exactly - is unknown.Ichthyosaurs appeared in the Permian period, although the most ancient remains of these reptiles dating back to the lower Triassic period.
Externally ichthyosaurs repeats the shape of today's fish.Their triangular head with outstretched jaws head resembled dolphins.Laterally flattened body, vertical blade tail and paws, turned into fins, making them different from all its predecessors water.
giant floating among dinosaurs
His name liopleurodon.It is the largest aquatic predators of all time, is the most studied species.Its dimensions are still the subject of scientific dispute husbands.According to most experts, liopleurodon in length can reach 25 meters and weigh - up to 150 tons!According to some, it is the largest predator that ever lived on Earth.By the way, he belonged to those already mentioned, and plesiosaurs lived in the Jurassic period.
