Protsarstvovav on the Earth of 160 million years, dinosaurs have disappeared from the person of a planet about 65 million years ago.
Scientific knowledge about dinosaurs are formed mainly on the basis of studying of fossils - the fossil remains of plants turned to stone or animals. Paleontologists (the experts studying ancient forms of a life) have made to themselves accurate enough representation about an origin of dinosaurs, their anatomy, a way of life, a variety of kinds, an inhabitancy, reproduction and distribution in prehistoric the world.
On small defects of fossilized bones experts can judge the muscular device of dinosaurs, and by the form separate bones - about what ancient pangolins were ill. Careful studying of a skull of a dinosaur provides guidance on size of a brain and a food of a reptile. About cubs of dinosaurs will tell fossil eggs. Where it is more difficult to find acknowledgement to other hypotheses - for example, whether there was at ancient reptiles a scalp and what colour there was their skin.
the Epoch of dinosaurs
All history of the Earth from its occurrence approximately shares 4500 million years ago on an era. The epoch of dinosaurs covers the most part mesozoic, or average, an era. It in turn consists of three periods - Triassic (256-208 million years ago), jurskogo (208-146 million years ago) and cretaceous (146-65 million years ago).
Reptiles existed on the Earth even before occurrence of dinosaurs. In the beginning of the Triassic period there was a set of new kinds, for example, swift-footed kinodonty ("ёюсръючѕс№х"), hunting on slow herds of herbivores. At the most ancient reptiles of a paw trunks, as at the majority of modern lizards have been located on each side.
It on change have come arhozavry ("уюёяюфё=тѕ¦Ёшх ЁхЁ№"). One group of these reptiles differed from other a body structure - their finitenesses were vertically under a trunk. Possibly, from here that successful skeletal design which we find at their descendants - dinosaurs ("ѕцрёэ№§ ЁхЁют" also originates;). By the end of the Triassic period by the ground the first present dinosaurs already walked about. However blossoming of their epoch has had for the cretaceous period when number and a variety of kinds of these reptiles have reached apogee.
For today scientists have allocated over 1000 kinds of dinosaurs which accurately share on two groups - travojadnyh and carnivorous pangolins.
The Sizes of dinosaurs fluctuated from the kid-predator kompsognatusa in size of no more cock to huge zauropod (" ЁхЁюэюуш§"). It were travojadnye giants with a huge trunk, a little head and long as at giraffe, the neck, allowing to reach delicious leaflets on tops of trees. Foreteeth similar to nails they broke foliage from branches, and the stupid radical chewed them.
Diplodok ("фтющэющ ЁхЁ") reached 26 m at length and weighed 11 tons. Brahiozavr (" ЁхЁ with Ёѕърьш") was in the length 28 m, in height 13 m and weighed 100 tons - as much, how many 16 African elephants. Brahiozavry ate only plants and to survive, should eat in day about ton of leaves. In skeletons of some minerals zauropodov huge stones in that place where there should be a stomach have been found out. Apparently, they helped to crush rough branches and leaves in the course of digestion.
Many travojadnye dinosaurs in search of a forage moved groups. Quite often they got off in the big herds more successfully to beat off from predators. So arrived, say, tritseratops, protecting the cubs. In case of an attack adult individuals surrounded young growth approximately the same as now it is done by elephants.
However, many "ьшЁэ№х" dinosaurs too have been decently armed. Tritseratops rushed to fight like a rhinoceros and pierced the enemy two huge sharp horns located in a frontal part of a snout. Pinakozavry deafened the opponent by blows of a heavy bone outgrowth on a tail tip. Others travojadnye pangolins, like stegozavra, have been protected by numbers of large bone plates along a back and sharp tail thorns.
The sharp teeth of predatory dinosaurs Bent inside allowed to tear a victim to pieces, and long sharp claws kept it on a place. 12-metre tirannozavr (" ЁхЁ-=шЁрэ") was largest of carnivorous dinosaurs and weighed more than 8 tons. Its bent teeth reached 16 sm at length - almost about a palm of the person.
The Majority of carnivorous pangolins, including tirannozavra, moved on two hind legs so, could run quickly in a pursuit of extraction. In the top part of a trunk there were short forward finitenesses. They came to an end with similarity small "Ёѕёхъ" with two sharp-clawed fingers on everyone. Scientists do not have confidence of how tirannozavr used forepaws, but it is possible to assume that them it kept extraction. According to some experts, they served a pangolin small, but strong props with which help it rose on hinder legs after a dream or rest. The ruthless murderer - velotsiraptor, means whose name "яЁютюЁэ№щ уЁрсш=хыі" - attacked small mammals or dinosaurs of one of the long hind legs, keeping balance by means of a tail, and broke off extraction by long crescent claws.
Despite dimensions, dinosaurs could move very quickly. Long-legged "ё=Ёрѕёют№х" dinosaurs ran with a speed to 50 km/hour. Heavyweights, like 35-ton apatozavra, moved with speed of an elephant, and slow 100-ton brahiozavr hardly could exceed 4 km/hour.
To move, zauropodam strong feet were necessary. An elastic step "ё heels on ярыіч№" like human, demanded too big expenses of energy, and such step the large dinosaur would not come far. Zauropody went more likely, than walked. To support a massive trunk, their finitenesses should go all plane of a sole. Therefore between fingers and "я =ъющ" they had a thick become horny platen, as on a sole of a modern elephant.
Long time was considered that dinosaurs built nests and postponed eggs. But as the young growth was grown up, remains a riddle up to 1978 when the nest has been found in the State of Montana (USA) with newborn kids and an egg shell. Some cubs were in the length to 1 m though the length of egg did not exceed 20 see Found dinozavriki were too great to be newborns, means, they remained in nests still long time after birth.
On the basis of this data scientists have come to a conclusion that parents looked after kids until those did not grow up enough to take care of themselves. At many cubs found in Montana a teeth has been clenched - means, parents brought up them in a nest, as birds.
There are all new that certificate that some large kinds of dinosaurs were viviparous, like mammals. As many dinosaurs constantly moved in search of a forage and, escaping from enemies, at them would not be to postpone time of egg and weeks, and even months, to wait occurrence and a posterity growing. Besides, the largest found egg of a dinosaur does not exceed 30 sm at length. The kid hatching from it was only nenamnogo and should, very quickly grow to reach the sizes of the adult individual.
the First fossils
In 1822 Gideon Mentsll has found any huge teeth in a stone quarry of a county of Sasseks. Having noted their similarity to a teeth of the South American lizard iguany, he has guessed that a fossil teeth belongs to a reptile, and has thought up for it the name iguanodon, i.e. "шуѕрэючѕс№щ".
Fossil remains of dinosaurs find "a life Origin" almost in all corners of the world and on all continents, including Antarctic. Bones and a teeth more often come across, i.e. Elements of a skeleton which give in to decomposition, than soft fabrics much less.
The Second place is occupied with prints of traces. Often them find on the tracks laid by dinosaurs in a soft ground. In the wake of it is possible to define places of moving of pangolins and who on whom hunted. Fossil prints of traces name residual fossils.
Koprolity (the hardened excrement of dinosaurs) prepare and investigate along with contents of intestines and gastric stones to find out, than ancient pangolins ate. Prints of a skin of dinosaurs have been found also.
But nobody knows, what colour there were dinosaurs as the skin decays too quickly, without having time to harden. According to some scientists, predatory pangolins had the protective colouring allowing them to merge with district imperceptibly to creep to extraction. Other reptiles, for example, travojadnye, were so great that could not be afraid of predators, and, probably, had bright colouring to involve individuals of an opposite sex.
In the end of the cretaceous period, about 65 million years ago, dinosaurs have died out. In this respect there are some theories. According to one of them, near to the Earth there was an explosion of the star which have shrouded a planet by killing radiation.
Found out on peninsula Yucatan in Mexico traces of a huge crater suggest about collision with the Earth the huge meteorite, accompanied by powerful explosion. The dense clouds which have shot up in atmosphere of a dust for some months have hidden the sun and almost have completely destroyed a life on a planet.
Other scientists believe that dinosaurs have died out owing to climate changes. But we, apparently, do not learn the true reason of their destruction never.
- That a word "фшэючртЁ" (in a Greek way "ѕцрёэ№щ ЁхЁ"), doctor Richard Ouen in 1841 for the first time has applied
- That the champion-heavyweight among known dinosaurs is ultra-zavr, whose remains have been found out for the first time in 1979 By some estimations it weighed 130 tons.
- That the largest egg of a dinosaur has been found in France. It was size about a ball for Rugby football and is postponed zauropodom, huge gipselozavrom.
- From living animals all ever on the Earth at stegozavrov there was the smallest brain in relation to body gross weight. At 2-ton weight and 6-metre length of a pangolin its brain was size only about a walnut.