It's no secret that unique animals lived in the ancient world, which, unfortunately or fortunately, we were not destined to see. But the massive and huge remains testify to the greatness and strength of these mammals. So, in the past, animals adapted to the environment, and even individuals of the same species could change under its influence. Many are interested in such a unique mammal as the mastodon. This is an animal from the order of proboscis, which in many ways resembled mammoths, but also had differences from them.

Characteristics of mastodons

Nowadays, no one thinks that, perhaps, the mastodon is the brightest ancestor of the ordinary elephant. The main common feature of animals, of course, is the trunk, as well as their enormous size compared to other inhabitants of the wild. However, it was found that the mastodons were no larger than the elephants that we can see today in zoos or on TV.

Mastodons are considered extinct mammals. They had similarities with other representatives of the proboscis order, but differences were also present. The main one is these large mammals on the chewing surface of the molars had paired papillary tubercles. And mammoths and elephants on molars had transverse ridges, which were separated by cement.

Origin of the name "mastodon"

It is interesting that the mastodon is translated from Greek as "nipple", "tooth". Consequently, the name of the animal comes from the peculiarities of the structure of its teeth. Note that some individuals had tusks in the lower jaw, which (according to scientists) were transformed from the second incisors.

Mastodons were considered herbivores, incapable of harming any of their neighbors in a large house called Wildlife. The main dish of the proboscis detachment was also shrubs. Nevertheless, if mammals were frightened, they simply could kill a nearby animal with their enormous weight as a result of a sudden movement, without wanting to.

Male mastodons

Some scholars are convinced that the mastodons did not exceed the growth of an ordinary elephant. The males of the proboscis order could reach three meters at the withers. It is worth noting that they preferred to live separately from the herd, that is, females and their cubs. Their sexual maturity was reached by the age of ten or fifteen. On average, mastodons lived for sixty years.

It is also worth noting that there were different types of mammals (the American one was described above), and almost all of them were similar. But in fact, mastodons appeared precisely in Africa. This was 35 million years ago. A little later, they moved to Europe, Asia, North and South America.

The mastodon provides for an influential figure, something big, for example, a business mastodon, a literary mastodon), unlike an elephant, had tusks in the upper and lower jaw. A little later, the species of the proboscis detachment changed, and the number of canines decreased to one pair. Scientists have found that about 10 thousand years ago. There were about twenty types of them.

One of the versions of the extinction of mastodons was the infection of mammals with tuberculosis. But after their disappearance, they did not remain forgotten. Scientists are constantly studying the bones, tusks of mastodons, making new discoveries and delving into the history of unique mammals. In 2007, the animal's DNA was examined from its teeth. The study proved that the remains of the mastodon were from 50 to 130 thousand years old.

Thus, the mastodon is a unique and incompletely studied large mammal that walked the earth tens of thousands of years ago and was considered one of the most benevolent animals. It is proven that over time they began to eat grass, preferring it to the leaves of trees and shrubs, although their massive tusks were conducive to excellent hunting.

In 1959, British chemist John Kendrew figured out the structure of the muscle protein myoglobin and three years later received the Nobel Prize for this discovery. Half a century has passed, but this protein continues to be the subject of active study and reveal sometimes unexpected secrets. In a recent issue of Science, biologists from the UK, USA and Canada talked about the characteristics of myoglobin in cetaceans and how long the ancestors of some modern mammals spent underwater.

It's not just the sheer amount of myoglobin that makes aquatic mammals long underwater, new research has shown. The point is that the surfaces of these proteins carry an excess positive charge in these animals, due to which the molecules repel each other. This ensures non-sticking of myoglobin in such huge concentrations - otherwise it would turn into non-functional protein masses.

But the biologists did not stop there either - they restored myoglobins for the ancestors of some land animals. The result was surprising: modern elephants, hyraxes, moles and echidnas come from animals whose myoglobins were so well charged! Interestingly, a recent article suggested, based on fossil bones, that the ancestors of echidnas were swimmers. Other paleontologists have hypothesized about the aquatic ancestors of elephants and moles. Thus, myoglobin is simply repeating the story that the bones began to tell.
We have no idea what the common ancestor of elephants, hyraxes, manatees and walruses looked like - we do not have its bones. But there is a tiny molecule, thanks to which we can confidently say that his muscles were adapted for diving.

Prepared based on materials

Trogonteria elephant - the ancestor of the mammoth

The trogontery elephant (Mammuthus trogontherii), also called the steppe mammoth, lived 1.5 - 0.2 million years ago, and the latest trogontherian elephants lived side by side with mammoths. The trogontery elephant, mammoth, like modern elephants, belong to the same elephantid family. The mammoth and the trogonterian elephant are very close relatives, since the mammoths descended from the trogontherian elephants. Moreover, the trogontery elephants appear to have been the ancestors of the American mammoths as well.

The trogonteria elephants lived in North Asia 1.5 million years ago, where it was not as cold as it is now, and then from this area they spread throughout the Northern Hemisphere, even reaching Central China and Spain.

Mammoths lived in Eurasia and North America - after all, at that time an isthmus existed on the site of the Bering Strait, and it existed for a very long time. From time to time (for 30-40 thousand years) it was covered by the glacier of the American Arctic shield and except for birds no one could get to America and back. When the glacier melted, the way was opened for other living beings. At the beginning of the Middle Pleistocene epoch (more than 500 thousand years ago), the ancestors of mammoths - the trogonteria elephants, apparently penetrated into North America, settled there and American mammoths descended from them. This is a separate branch of mammoth elephants. Their scientific name is the Colombian mammoth (Mammuthus columbi). Later, in the Late Pleistocene epoch (70 thousand years ago), the mammoth proper (woolly mammoth –Mammuthus primigenius) entered North America from Siberia, and both species of mammoths lived side by side in America.

The remains of mammoths make it possible to determine what the mammoth lived on, what it ate, what the mammoth was sick with. The bones of mammals are a “matrix” on which there are traces of growth, diseases, individual age, injuries, etc. For example, only on the basis of the bones of mammoth cubs from the Sevsk locality (Bryansk region) it was found that mammoths at birth were 35-40% smaller than the cubs of modern elephants, but in the first 6-8 months of life they grew so quickly that they caught up with children of their modern relatives. Then growth slowed down again. This suggests that in winter, which just began at the 6-7th month of the life of a newborn mammoth, he ate worse, the mother could no longer feed him with milk. Therefore, the baby mammoth began to eat the same food as the adults. The erasure of the mammoth cubs' teeth confirms this. In mammoths, the teeth of the first shifts began to wear out and wore out much earlier than in the young of modern elephants.

A group of mammoths from Sevsk, most likely, died as a result of a very strong flood, which cut off their exit from the river valley, and this happened at the very beginning of spring. River sediments, in which there were bones, show how gradually the strength of the current weakened and in the end the place where the corpses of mammoths remained turned first into an oxbow, and then into a swamp.

Living things are born, mature and die. If nothing happened to the nature around, many generations replace each other, year after year, century after century. But if something changes, it becomes colder or, on the contrary, hotter, living beings either adapt to these changes, or die out. Extinction of living beings due to catastrophes are extremely rare events. The existence of one or another group of extinct living things ended for various reasons ...

The reasons for the extinction of mammoths are associated with climate change. Mammoth and man lived on the Russian Plain, side by side for more than 30 thousand years and no extermination took place. Only after the climate change that began at the end of the Pleistocene period, the mammoth became extinct. Nowadays, the hypothesis that the huge rubble of mammoth bones from the Paleolithic sites is not the result of hunting, but traces of the collection of mammoth bones from natural locations, is gaining more and more popularity. These bones were needed as raw materials for making tools and much more. Of course, man hunted mammoths, but there were no tribes that would have been engaged in specialized hunting for them. The biology of the mammoth is such that it could not be the basis of human life, the main game species were horses, bison, reindeer and other animals of the Ice Age.

Our ancestors, of course, hunted, since the ancestors of humans refused to eat grass more than 3 million years ago - this is not a productive way of evolution. But the Australopithecines followed this path and in the African savannas they grazed in the meadows along with the ancient baboons - gelads and antelopes, but died out when the climate in Africa became more arid.

In order for a person to eat someone, he must first be caught. Ancient man had only one device for this - his brain. Using this "tool", people gradually improved their hunting tools and techniques. Without tools and weapons, a person has no chance of catching another animal. The history of the human race is very long and shows that it was not always possible to successfully find food for themselves. Yes, we have to admit that ancient people also ate the corpses of animals, at least at the earliest stages of human history, including the mammoth ...

These amazing primitive mammals

These amazing primitive mammals

Remained in the shadow of history
The first mammals appeared on earth 265 million years ago, 10 million years after the first dinosaurs. However, the first 160 million years, when the dinosaurs ruled, they remained in the shadow of history. The ancient ancestors of reptile mammals lived about 300 million years ago therapsils... They are very similar to us.

The very first ancestor of modern mammals

was found by paleontologists in sediments of 570 million years, in southern China. One group of scientists discovered primitive sponges, another - embryos in the early stages of development, which have the same structure as all modern mammals.

Oldest mammal

Megazostrodon (1966), found in Taba Litau, Lesotho, estimated to be 190,000,000 years old.

The oldest mammals

The oldest mammal-like animal with tusks
Large tusks were evidence of the sexual separation of land animals. The oldest animal with tusks lived in Europe before the advent of dinosaurs. It was a male dictodon, a barrel-like herbivore, possessed two tusks descending from the lower jaw. The age of his remains is 252-260 million years. Dictodon appeared in the late Permian period of the Paleozoic era, at least 30 million years earlier than dinosaurs appeared. He belonged to the group of mammalian-like reptiles and was an evolutionary relative of animals, from which mammals later descended. In length, it reached 70-80 centimeters.

Why did the dictodon need tusks?

These fangs were used as weapons - perhaps in mating ritual or physical encounters. They were not used for obtaining food, since the females did not have them. They also could not dig or dig the earth - since no signs of wear were found on the ends. It seems that the tusks became longer, wider and thicker as the animals aged, but if the animal lost them (for example, in a fight), new ones did not grow. All this suggests that the tusks were part of military equipment.

Mastodon

Mastodons (proboscis) living in the Pleistocene were the size of an elephant; they lived on all continents.

Ancestor of elephants and rhinos

Scientists are aware of six new species of large prehistoric mammals that roamed mountainous Ethiopia 27 million years ago. These include the ancient ancestor of the elephant and the rhino-like animal. These are Africa's own mammals, which became extinct, unable to compete with Eurasian lions, tigers, hippos, hyenas and antelopes.

Mastodon - the largest mammal of the glacial times

Elephantine Mastodon americanus lived in North America during the Pleistocene until the end of the glaciation. The length of its body was 4.5 m, the length at the shoulders was 2-3 m. This animal became extinct due to the warming of the climate. It belonged to the family Mammutidae, originating from North Africa, which spread to Eurasia and North America 15 million years ago. It got its name from the "tooth" ("nipple tooth"). It is known that the mastodons who lived in the middle of the glacial era were smaller in size than their counterparts who later lived in the forests. Later mastodons adapted to life in coniferous forests and swamps. They used their tusks to break tree branches. The mastodon's tusks were short and straight, and the teeth were sharp. The females were smaller than the males, and their tusks were also smaller and lighter. They were covered with a thick undercoat (5-18 cm long). Fossil remains of mastodons have been found in the North of the United States and Canada. The honor of discovering this animal belongs to Baron Cuvier.

The darkest period in African history

Falls at a time of 24-32 million years ago. It was then that the prehistoric continent known as Afroaravia began to merge with Eurasia. After this "contact" immigrants settled in Africa - lions, tigers, hippos, hyenas and antelopes. Before the connection took place, Africa developed many of its own mammals. They died out without ever seeing Eurasia.

Cave lion

Scientists have found drawings and bones of cave lions in the grottoes of Spain, France, England, Belgium, Germany, Austria, Italy, Algeria and Syria. There was a time when lions lived not only in Africa, but also on the Arabian Peninsula. In Persia, Northwest India and even in Turkey, Greece, the Caucasus and the lower reaches of the Don. Traces of lions have been found in the Ukraine near Odessa, Tiraspol, Kiveom and even in the Urals and in the Perm region.

Saber-toothed tiger - Smilidon californicus

... inhabited North America (California) and South America (Argentina) during the late Pleistocene. He had a body 1.2 m long and a short tail, like a manul cat. A pair of long upper jaw teeth helped to cope with prey. His shoulders and neck were muscular. Saber-toothed tigers attacked slowly moving prey, because they needed time to sink their huge teeth into the victim. This is the hypothesis.

Fangs 40 cm

Have saber-toothed tigers - Smilodon fatalis there were terrible 40-centimeter fangs.

Scull mahairoda- so called saber-toothed tigers, which lived for about two million years. It was sold in Los Angeles for $ 200,000.

Ancient elephants were fishing

Fragments of the skeleton of a poorly studied subspecies of elephants that lived on Earth 15 million years ago were found forty kilometers from Munich. His tusks were rounded, with which he could dig out plants and even fish.

Ancient elephant

Was a terrible animal A fossilized tusk, teeth and bones of a prehistoric ancestor of an elephant was discovered in Crete Deinotherium gigantissimum, whose fangs went down from the chin. The growth of the animal reached 4.5 meters, and he was the largest representative of the Doslon group. His remains are about 7 million years old. Until now, his remains have been found mostly in Central Europe. Fassoulas suggests that these creatures reached Crete from Asia Minor, crossing the Aegean Sea and visiting the island of Rhodes and Karpathos on their way. Apparently, primitive elephants in search of food could swim long distances.

Myths turned ancient elephants into cyclops

The remains of ancient elephants have long been found in the mainland of Greece. This suggested that the ancient Greeks made these animals a part of their mythology. A large hole in the center of their skull - the nasal cavity, hidden by the trunk of a living elephant, could become the source of stories about cyclops, mythical giants with one eye, mentioned in Homer's Odyssey and other works.

Paleoloxodon elephants, whose growth exceeded 3 meters, lived tens of thousands of years ago (in the Pleistocene epoch) in a cold climatic zone in the territory of modern northeastern China and Japan.

The evolution of ancient elephants can be traced by changing molars.

The Mastodon had small, breast-toothed teeth with three to four teeth, not too prominent. Stegodon, the immediate ancestor of modern elephants, had roof-toothed teeth and was already much larger than the mastodon. The primeval elephants Primelephas, to which the stegodon belonged, gave rise to the later extinct mammoths Mammoths and two modern species, Loxodonta and Elephas.

Stegodon - dwarf elephant

Lived on the island of Flores (Indonesia).

Woolly mammoth (Mammuthus primigenius)

... this well-known contemporary of the glacial era (late Pleistocene) was reliably protected from the cold by a thick layer of subcutaneous fat and long hair. A hump with reserves of fat was located right behind his majestic head. In size, the mammoth was inferior to other members of the family, the height at the withers was 2.7 m. Mammoths grazed in the tundra, eating low vegetation, which they had to extract with tusks directly from under the snow. Known from the remains. Found in Siberia and Alaska, as well as from rock carvings in caves in Spain and France, where primitive artists left evidence of their encounters with mammoths.

What were the teeth of a mammoth

The mammoth species Mammuthus planifrons and Mammuthus meridionalis known to us had teeth with 12 and 14 teeth, respectively, and the woolly mammoth Mammuthus primigenius had teeth with 27 teeth, which was due to the peculiarity of its diet.

Herds of mammoths grazed in Siberia

DNA obtained from excavations in Siberia shows that in the past, herds of mammoths grazed in the thriving tundra. However, 11 thousand years ago, as a result of climate change, pastures began to disappear, which could lead to the disappearance of some of the animals.

The origin of predators

Predatory animals descend from the primitive insectivores of the Cretaceous period. They are closely related to the primitive carnivores Creodotita, which make up a special extinct suborder of carnivores, numerous in the Paleocene, flourishing in the Eocene and disappearing in the Miocene. In the Miacidae family, they are small animals with an elongated body, short legs, a long tail, and a rather large brain. Miacids lived in forests, trees and looked very much like real beasts of prey.

The first small representatives of the order of predators resembling civet or marten in appearance and way of life, appeared in the Upper Eocene. In the Oligocene, carnivores occupied a dominant position among other terrestrial carnivores and reached such a variety that all the main seven families that exist to this time were outlined among them.

The canine family is considered the most ancient.... Already in the Upper Eocene, primitive dogs lived in North America and Europe, in many respects rather similar to civets or martens. In the Upper Tertiary time, among the canines, the initial adaptive types began to emerge, from which modern genera of dogs, foxes, and others developed in the Upper Miocene and Pliocene. In the Miocene and Pliocene, it was widespread not only in America and Asia, as at present, but also in Europe.

Cave bear

The bear family belongs to the same group as the dogs. It arose in the Middle Miocene, and in the Pleistocene, bears appeared belonging to the modern genus of bears (Ursus), but distinguished by their enormous size. Cave bears that lived in the Pleistocene had a body length of about 3 m; they lived in Eurasia.

Cunyi - the latest group

The weasel family originated in the Oligocene. By the Miocene, among them, the main systematic groups were outlined, associated with various directions of adaptation to the environment and different lifestyles. Many species and genera of mustelids became extinct in the Tertiary and Quaternary periods.

Ancient wivvers

The group of carnivorous viverrids is the most ancient of its modern relatives of the suborder Aeluroidea (or Feloidea). ... In the Oligocene and even later, civets were distinguished not only by a variety of forms, but also by a much more extensive distribution than now. They were widely represented in the territories of Europe and Asia, but were absent in America. At the end of the Miocene, hyenas branched off from the civerrids. The most ancient of their representatives were very similar to their ancestors - the civet, but later, as they switched to feeding on carrion, they acquired modern characteristic adaptive features. The most specialized among carnivores, the cat family, apparently, arose at the end of the Eocene, and in the Oligocene it reached a great variety and wide distribution.

Primal wolf Canis lupus

A relative of modern forest wolves lived in European forests of the Pleistocene era. For hunting, wolves gathered in packs. Adult wolves reached a length of 2.5 m (6 feet) and a height at the withers 1.3 m (3 feet). They ate small mammals, sometimes large ones. The ancient ancestor of marsupials was the size of a mouse Discovered in the mountains of China, the skeleton of a creature that is considered the most ancient ancestor of modern marsupial mammals - possums, kangaroos, koalas and others. The remains are 125 million years old - they are 15 million years older than previous finds by scientists. In addition to the skeleton, clear prints of fur and fabric were found. All this made it possible to reconstruct the appearance of an ancient creature. The animal that lived with the dinosaurs was small - about the size of a mouse: about 15 centimeters long and weighing about 30 grams. The structure of the limbs indicates that the creature was able to climb trees.

Common ancestor

All the predatory animals of Madagascar had one common ancestor who lived on the African continent before he came to the island 18-24 million years ago. He crossed the water barrier that separates the island from the African coast.

Condilartr - the ancestor of the hippopotamus
The first species of hippos appeared 54 million years ago, in the Tertiary period of the Cenozoic era. Like other ungulates, the genus of hippos, or hippos (Hippopotamidae) descended from the ancient animal condilarter.

From the life of ancient hippos

Fossilized bones of two ancient hippos have been discovered in Norfolk, England. Their age is estimated at 450 thousand years (there is reason to judge that they may be 50-200 thousand years older). Hippos weighed six to seven tons - about half the size of their modern descendants. They had unusual eyes - which served as periscopes after submersion. In the ground, they lay next to the remains of a hyena, a horse, fish and several rodents. Apparently, the hippos died of natural causes, and their bones were gnawed by hyenas. All of these animals inhabited these places at a time when the vicinity of Norfolk was inhabited by a mixture of familiar plants and animals and more exotic species, which are now more common in the African savannah. In the Pleistocene average, the average temperature was about two degrees warmer than it is now.

Cave bear (Arctodus simus) lived during the Pleistocene.

The primitive rodent was about the size of a bull

In the semi-desert of Venezuela, they discovered the fossilized remains of a creature that, in their opinion, was the largest rodent in history. It weighed about 700 kg, reaching a length of 2.5 meters (excluding the tail). His remains were found back in 2000 in one of the marshes of Venezuela, 400 km west of the capital of the country, Caracas. The formal name for this rodent is Phoberomys pattersoni, and unofficial - Goya (Goya). According to scientists, he lived 6-8 million years ago in swampy forests, when South America was isolated from the rest of the world. The herbivore Goya had a large tail that allowed it to balance on its hind legs to watch for predators. And the rodent had plenty of enemies: 10-meter crocodiles, marsupial cats, giant birds of prey. It was they who, in the end, ruined him.

Primitive bull - Bos primigenus

May be considered the ancestor of modern cattle. He inhabited North Africa, Europe and Asia from the Pleistocene to the 10th century AD. The bull was first domesticated 6,000 years ago; the last bulls became extinct in the 17th century AD. The bull was about 3 m long.

Very ancient cats

25 million years ago there were ancient ancestors of wild cats Proailurus who formed the groups Noefelids, Pseudaelurus, and Palaeofelids. From the Noefelids came the saber-toothed tigers of the genus Smilodon (the most famous) and Homotherium. The predators Dinctus and Barbourifelis originated from the Palaeofelids group. The Noefelids and Palaeofelids groups turned out to be dead ends and became extinct much earlier than 10 million years ago (the exception was the predatory cats Barbourifelis, which crossed this line).

The line of predators Pseudaelurus turned out to be promising, which 10-5 million years ago was divided into cheetah and cougars (they were the first to separate from the common trunk 10 million years ago), lynxes (emerged about 7 and a half million years ago), panthers (5 million years ago) ... Later, the genera of small cats and the clouded leopard were formed (4-3 million years ago). Modern species were formed after the turn of 1 million years ago.

Ancient finds are represented by single bones. The most fully represented is the ancient lynx, which lived 4 million years ago. (Lynx issidorensis). It was larger than modern, had shorter front legs, and the hind legs were longer.

Blood relatives were 2 million years ago

The jaguar and leopard seem to have a common ancestor that lived in Central Europe over 2 million years ago. Later, the relatives split up: the leopard began to inhabit western Europe (1 million years ago), and the jaguar at the same time moved across the Bering Isthmus to North America. The jaguars of those times (Panthera onca augusta) were larger and more leggy than their offspring. 750,000 years ago, they began to decrease in size due to adaptation to local climatic conditions and diet. 100,000 years ago, the jaguar took on a form similar to the one that is found today.

The saber-toothed tiger was on his own

Many people are mistaken to believe that the prehistoric saber-toothed tiger is the ancestor of modern tigers. They had no common ancestors. Saber-toothed tigers became extinct before the ancestors of modern tigers appeared.

Saber-toothed tiger Smilodon hunted by pride

The saber-toothed tiger Smilodon was about the size of an average lion, but its head was very large in proportion to its body. Its tail was short, which allows us to conclude that the saber-toothed tiger did not pursue its prey at long distances, limiting itself to pursuit at short distances. There is evidence that saber-toothed tigers were social animals and hunted in packs similar to how the pride of lions hunt now.

The ancestors of tigers lived for 2 million years

Back in Central Asia and China and were distributed both in the west and in the east of the region from the Caspian Sea to the Far East and Primorye. 1 million years ago, giant tigers were still found in China. The features of this ancient tiger are largely preserved by the North China tiger. Tigers shrank in size 250,000 years ago.

Cheetah ancestors

... lived in North America 2½ million years ago), and along with the giant cheetah Acinonyx Studeri, there was also a small species Acinonyx trumani (which lived 12,000 years ago). The ancestors of the modern cheetah Acinonyx pardinensis from Europe resembled its modern descendant, only surpassed it in size.

Of the panthers, the lion was the first

Of all the Panthera panthers, the first to appear was a lion, whose remains date back to 750,000 (West or East Africa). They were larger in size than modern ones and are considered gigantic. From there, 250,000 years ago, lions spread to North Africa and Europe, where the cave lion (Panthera spelaea) and the Tuscany lion (Tuscany lion) lived in northern Italy and the Balkans. From Asia, lions moved to North America and formed the species (Panthera atrox), which spread all the way to Peru in the south. 100,000 years ago, ancient lions became extinct without being able to adapt to changing climatic conditions.

This predator was found throughout the Pleistocene throughout North America (including Alaska), as well as in northern South America. In length, it reached 3.5 m. It had sharp retractable claws and sharp teeth (shorter than other relatives). Other subspecies of the American lion are found in various parts of Africa and western India.

Giant battleship

The giant armadillo that lived in the Pleistocene had a body length of 4 m; lived in South America.

The rabbit that lived 55 million years ago

The fossil remains of the world's oldest rabbit, Gomphos elkema, lived 55 million years ago and is considered the most ancient ancestor of the modern rabbit. It is believed to have moved in much the same way as the modern rabbit, jumping with its elongated hind legs. Despite the obvious similarities, gomphos differed in several ways from modern rabbits. So, he had a very long tail, and some of his teeth looked more like the teeth of a squirrel than a rabbit.

Mesozoic badger eating dinosaurs

An animal that looks like a badger Repenomamus giganticus was about the size of a large dog, over one meter in length. It is one of the largest mammals of the Mesozoic era. Its jaw is about the size of a fox's. Inside the skeleton of this animal, which lived about 130 million years ago in northern China, scientists have discovered a small skeleton of a baby dinosaur. Probably Repenomamus giganticus ate dinosaurs. The ancient badger, most likely, tore the victim apart and swallowed in large chunks. This theory is supported by the fact that a mammal with sharp incisors lacks molars, and its sharp teeth are intended for something completely different - for tearing apart and eating other animals. Although it could also feed on plants and insects.

The oldest primates

Unidentified monkey (May 1979), found in Padaung, Burma, estimated to be 40,000,000 years old; a lemur found in Madagascar, estimated to be 70,000,000 years old; tarsier primate found in Indonesia, estimated to be 70,000,000 years old.

Giant sloth

The giant sloth megatherium, which lived in the Pleistocene, had a body length of 7 m; he lived in South America, it was a land animal.

Beavers were the most
Paleontologists have long believed that mammals that lived alongside dinosaurs were animals that looked like tiny shrews. Meanwhile, a fossil of a beaver-like mammal that lived 164 million years ago was found. The semi-aquatic mammal had a body length of about half a meter and a weight of 500 g, partly resembled a platypus, partly an otter and partly a beaver. This animal is the largest of its kind, and belongs to the Jurassic period (from 200 to 145 million years ago).

Primitive whales

Fossil remains of primitive whales, zeuglodonts ("jugular"), have been found in marine sediments in Africa, Europe, New Zealand, Antarctica and North America. Some of them were giants over 20 m in length.

Which mammal was the ancestor of modern cetaceans?

Too little fossil remains have been collected on this matter. Perhaps these were primitive creodontic predators, perhaps ungulates, but most likely ancient insectivores, from which cetaceans, carnivores, and ungulates branched off. Each of these concepts has its own arguments.

The ancestors of whales are ungulates
Some scientists consider the ancestors of cetaceans ungulates, since both have a multi-chamber stomach, multi-lobed kidneys, a two-horned uterus, the chemical composition of blood is similar and there are common features in the structure of the reproductive system (placenta, device and position of the penis, as well as the short duration of copulation), in the structure insulin and myoglobin molecules and in terms of the blood protein deposition reaction.

The ancestors of whales are predators
Other researchers are looking for the ancestors of cetaceans among creodont predators, guided by the structure of the skull and the peculiarities of the dental system. Primitive cetaceans had heterodont (different in shape) teeth, sagittal and occipital crests and zygomatic processes of the skull, to some extent similar to those of creodont predators (hyenodonts).

The ancestors of whales are insectivores
Based on the analysis of fossil remains, modern paleontologists are more inclined to believe that ancient cetaceans were associated with very early placentals, that is, the most ancient insectivores, and probably originated in the Late Cretaceous time even before the offshoots of ungulates and carnivores from them. 70 million years ago, the terrestrial ancestors of cetaceans migrated to the water.