The Tertiary Period. Eocene epoch

Duration of an Eocene epoch define approximately in 19 million years. From its termination till a modern epoch has driven about 35 million years. In Eocene the sea again attacked a land. Africa and the South America have not been connected more among themselves. There was no connection and between Northern and the South America. The African continent has broken up to three islands. Asia poprezhne incorporated to the North America, and America through Greenland and Atlantic ocean has been soldered to the Great Britain. The Western Europe and Scandinavia have formed the independent land lasting far on the north. Southern Europe, all south of the European part of Russia and the most part of the Central Asia have been filled in by a sea.

The climate in Eocene was warm. Fan-leaved and date palm trees former widely grew on northern continents which have been covered by evergreen woods.

The life of Eocene wood was rich and various. Among colours butterflies and other insects rushed. In the afternoon they were pursued by numerous birds, and night of an owl and bats. Many Eocene birds have lost ability to fly and ran, as modern ostriches. Some of them, for example North American Diatryma, differed huge growth which reached to 2 m. Similar pases of hedgehogs insectivorous mammals to the former lived on the earth, some of them conducted a wood way of life. In wood there lived the present semimonkeys, the first lemurs - small Notharctus. There were first rodents, on addition reminding modern squirrels, and also surprising tilloterias - animals in size from the large bear cub, similar on a structure of a teeth on rodents. Actually it not rodents, and original degenerates the insectivorous.

Ancient edentateses paleanodont were close to the general ancestors of all edentateses. Their representative metacheyramis, length about 0,5 m, on the general warehouse most of all reminded a modern battleship though the armour at it was still rudimentary. Forepaws metacheyramis have been armed by sharp and long claws with which it dug the earth, on hinder legs - claws short and stupid. Instead of the disappeared measured teeth in a mouth at it horn pillows were formed. Canines have been considerably increased.

Hiding in a shade of trees predatory creodontas became large, and strong animals. However, at some of them for example at dromocion and it was not formed the present predatory teeth, and claws became stupid. This long-legged runner almost reached, the sizes of a bear. Equal on size dromocion Patriofelis was a dense, stocky animal. Fingers of its wide paws incorporated a membrane. He lived about water and floated, possibly, otters are not worse. At Patriofelis there was predatory teeth, but they mismatched a teeth of the modern predatory.

Along with the named creodontas there were the small Miacidses similar to martens which predatory teeth quite corresponded on on-lozheniju in jaws to the same teeth of the modern predatory; the last are lineal descendants of Miacidses. Miacidses have won creodontas vital struggle. Their main advantage over creodontas consisted in rather already well developed brain; They were more dexterous, than creodontas, and with the big success could pursue herbivorous ungulate animals who by this time have considerably changed and improved. In the Eocene beginning fundamental hoofed animals - Condylarthra still Continued to live, but their number gradually decreased, and from the middle of Eocene they did not exist any more more. Amblypoda, descendants Paleocene Pantolambda, reached the huge sizes. So, the length uintatheres is more 4,5 m, and its height about 2,5 m. of Uintathereses had, except strong canines, also three pairs horns.

But neither huge growth, nor strong arms has not rescued Amblypoda from extinction. The insignificant brain and an imperfect teeth did not provide with it success in struggle for existence, they have given way on the Earth to other hoofed animals.

Imparidigitate hoofed animals were especially numerous in Eocene woods. Ancestors of horses concern them - Eohippuses. They are small animals, size about a fox. A teeth of Eohippuses with low bits specifies that these animals were fed by juicy, soft vegetation. Their four-fingered forward and tridactyl hind legs have been well adapted for circulation on soft, marshy soil of wood.

Wood bogs served as a refuge to heavy water rhinoceroses - to the amynodonts similar to hippopotamuses. Their length reached to 4 m. On more solid soil easily harmonous running rhinoceroses - Hyracodon moved. All rhinoceroses have been absolutely deprived horns, and this name is conserved behind them only because on skeleton structure and teeth they were similar a pas of modern rhinoceroses. In wood bogs there lived the ancestors of tapirs still deprived of a proboscis, and lophiodontses close to tapirs at which the proboscis has already developed. In woods of the modern Western Europe ancestors of horses have started to die out in the end of Eocene, and their place was occupied Palaeotheriidae, with tridactyl animals with a small proboscis. In the North America by this time have occurbed Palaeosips - the first representatives huge and two-horned titanotheres. Acerous Palaeosips was size from a tapir. On forward feet it had on four fingers, on back - on three. Its brain was amazingly small.

Artiodactyl hoofed animals at whom, as well as at pigs, deer and bulls, is stronger than other fingers develop centre and anonymous (under the account of 3rd and 4th), in the Eocene beginning lived a little more, In the end of their Eocene became much more. In Europe lived long-tailed aqueous anaploterias both reminding simultaneously a hare and a musk deer skipping small caenoterias. In the North America: were usual original four-fingered oreodont and absolutely strange long-tailed agriocherus. A teeth agriocherus is reminded by a teeth of a cow, their five-fingered lobbies and. Four-fingered hinder legs are armed kog. In America there were first ancestors of camels and the llamas, falling into Tyiopoda the artiodactyl. Tyiopoda these animals name because at them on a sole thick elastic pillows develop, hooves look like nails. These first camels - protylopus were still size from a rabbit. On forepaws for them was available on four fingers, on back - on two, fingers concluded still usual hoofs. In Europe instead of ancestors of camels lived close to them didactyle xidophontus. And relatives of pigs in Eocene we almost do not meet ancestors.

In the South America during described time there were absolutely special herbivores named notoungulates, or the South American hoofed animals. History of their infiltration into the South America difficult enough. The first representatives of these hoofed animals are more narrow in a paleocene lived in the Central Asia. From here they have removed to the North America and further have passed in Southern. After their arrival to the South America communication between Northern and the South America was broke. Hoofed animals and predators in the South America almost were not, therefore newcomers began to live safely on new continent. For the first of the South American hoofed animals small five-fingered animals with the increased chisels, as at rodents whom they remind on a way of life are known. The big finger on their forepaws could be opposed to the rests how it is observed at monkeys. Together with small South American hoofed animals fermented five-fingered Astrapotheria, size from a tapir. Their head with a trunk and the big canines reminded simultaneously a head of a tapir and a pig. Lived in the South America and so-called Litopterna which have replaced subsequently absent there not-artiodactyl hoofed animals.

In the North Africa in Eocene there were the first proboscidean, i.e. Ancestors of elephants. The most ancient proboscidean animal was Moeritherium, growth from a tapir. At Moeritherium, like a tapir, there was a small proboscis. It had four increased chisels (two in top and two in bottom jaws) which have formed small tusks. Almost simultaneously with Moeritherium there lived larger ancient mastodont. Tusks at it were longer, and the skull is shorter, than at Moeritherium, a teeth edge. It is an ancestor of all taxodont mastodonts.

On coast Tetisa in Eocene the first sea cows, or sirens floated. Sirens resemble whales, but unlike the last they are herbivorous and related the proboscidean. At Eocene sea cows, unlike modern, hinder legs were still conserved. Together with sirens especially surprising ancient whales - рыбоядные зейглодонты floated. These giants with a serpentine body reached 21 m at length, hinder legs at them any more were not, and lobbies have reverted in fins. A teeth of ancient whales, as well as at land mammals, was still divided into chisels, canines and radical that is not present at new whales. At the last or a teeth at all is not present (edentate whales) or all teeth is identical and has the form of a simple cone (зубастые whales).