Theropod dinosaurs are representatives of the bipedal carnivorous dinosaur squad. But this is also a suborder of lizards. They lived in prehistoric times, in the Mesozoic era, starting from the Triassic period. The heyday of their life fell on the Jurassic and Cretaceous period, the latter and became the sunset of the life of all dinosaurs.
Carnivorous "Feral" Dinosaurs
Theropods differed from all other dinosaurs in that they walked on two legs. The front legs were very small, not more than half a meter. Theropods almost never used them. Scientists still can not determine their purpose.
Among them there were both predatory and herbivorous dinosaurs.
Predatory dinosaurs were from huge to very small sizes. The oldest are found in the Triassic period. Scientists believe that their ancestors were some coelurosaurs from the group of carnosaurs, including tyrannosaurs. It is also believed that the origin of birds originates from theropods.
The most ancient predatory dinosaurs include: the record holder for length and weight - alivalia (8 meters / 1.5 tons), stavricosaurus, celophysis, herreraosaurus, herrerasaurids. The latter appeared at the very beginning of the Triassic period and became extinct before or at the beginning of the Jurassic period. They were relatively small in size, only 2-3 meters long and about 80 centimeters high.
Tyrannosaurus Rex - The Ferocious Theropod Predator
Tyrannosaurs have existed since the beginning of the Jurassic period. The only well-studied predator of the late Cretaceous is the tyrannosaurus rex. Theropod had a nasty bloodthirsty character, sharp teeth and brutal appetite, as well as a strong body, powerful legs and neck.
A huge head about 1.5 meters long rested on a short neck. In addition, he weighed almost seven tons and was 12-14 meters in length. With all his fierce appearance, he terrified all herbivores, even the largest dinosaurs. In food, he did not disdain anything, even small relatives.
Rex mainly fed on herbivorous dinosaurs, but could take the already killed prey from small predators. If he was very hungry, he could eat carrion.
Tyrannosaurus neighbors
Not only the tyrannosaurus possessed such a fierce disposition. Nearby lived other predatory dinosaurs of the Jurassic period. Here is a description of the carnivorous dinosaurs living next to the tyrannosaurs.
This is a ceratosaurus (North America), a “horned lizard,” on whose head a whole ridge of horns. The eight-meter metriacanthosaurus on its back wore an incredible sail, loved to eat a herbivorous dinosaur.
Ornitholest - a small predator - could run on two and four legs. Megalosaurus - up to nine meters in length, strong, muscular, with sharp teeth, a predator (the remains were found in Europe). Two bone crests flaunted at once on the head of a dilophosaurus, its body length was six meters. Quickly and skillfully moved on two legs.
Allosaurus is another Jurassic nightmare. A bloodthirsty reptile 11 meters long with strong strong hind legs, short three-fingered forelimbs with claws and a toothy mouth. Terrified all the inhabitants of the forests where he lived. Some scientists consider him the ancestor of the tyrannosaurus rex.
Another medium-sized (three meters long) formidable killer predator is the deinonych “monstrous claw”. On his both hind legs grew two murderous claw-blades that popped up like bandit's spring knives.
Small carnivorous theropods
In addition to large and medium-sized carnivorous dinosaurs, there were also small and very small theropod predators. The smallest dinosaurs fed mainly on insects, ants, small lizards, frogs, as well as dinosaur eggs.
For example, the dinosaur oviraptor (translated as a thief), devouring eggs, lived in East Asia. A small troodon dinosaur (USA) had well developed both hind and forelimbs, with which he could rake leaves and sand poured to shelter eggs. He crept up to the nest, grabbed an egg and threw it into his mouth, where he pierced it with sharp teeth.
The fastest predatory dinosaurs walkers
Fast medium-sized dinosaurs include segizaurs - with lightning movements and the embodiment of speed, with a huge, for its small growth, mouth with sharp teeth, which allows you to quickly swallow small prey.
Another walker - a podoseosaur (translated as a fast-footed lizard) - quickly, like lightning, grabbing a darting small prey underfoot. The compsognathus is the smallest, the length from the nose to the tip of the tail is 60 cm, and the growth is like that of a medium-sized chicken, but the most ferocious dinosaur.
It was because of such small carnivores that the life of herbivores, especially small cubs, became deadly.
Herbivorous dinosaurs from the Triassic period
The most ancient herbivorous dinosaurs, also called prosauropods, lived in the Triassic period (South America). They were not very large, for example, a masaurus, about three meters in length, but the Riohasaurus, found there, turned out to be much larger and more massive.
The remains of another ancient dinosaur nyasosaurus found in Africa, its length was only two meters. The tectonosaurus found in England turned out to be even more ancient. All representatives were similar to each other. They had small heads, long necks and tails, short forelimbs most often five-fingered and with claws. They could not raise their heads high (due to problems with the cervical vertebrae), they had to collect foliage (as food) from the ground or be content with shoots and branches that grew lower.
Herbivorous theropods of the Jurassic and Cretaceous periods
Descendants from the Jurassic and Cretaceous periods were called "poultry", they were very different in their enormous size from their ancestors. They became larger, more massive, the fingers on the front legs became three, instead of five.
None of the animals living on earth could and cannot compare with herbivorous dinosaurs. By creating them, nature has surpassed itself.
Apatosaurs (brontosaurs), diplodocus and brachiosaurus are real champions in height and weight. This large group of dinosaurs was called "sauropods."
- The most massive was the brachiosaurus, its weight was about 50 tons.
- The longest-necked one is the Mamenchisaurus, his neck was about 15 meters long.
- The longest tail has grown in diplodocus - as much as 12 meters.
- The shanosaurus turned out to be the most unusual tail; a bone outgrowth in the form of a mace grew at its end.
- Those who did not have very long necks: a camarasaurus, volcanodon, an uranosaurus with its magnificent sail on its back, which served for cooling.
Relatively small dinosaurs: iguanodon, psittacosaurus and proto-therapos with their beaks did not suffer much from a lack of food. Vegetation in the Jurassic period was enough for everyone, because trees and shrubs grew in abundance.
Caring mothers and their offspring
Dinosaurs, like most modern reptiles, laid eggs. This is confirmed by many finds of fossilized egg-laying, they differed in size and laying. In some dinosaurs, eggs were laid in a circle, in others in a spiral, in others in a line. An interesting fact: in the entire history of excavations, archaeologists have never found the eggs of a Rex tyrannosaurus.
Having arranged a nest in an earthen hole, the female laid eggs there, then covered them with leaves and small debris on top, so that predators would not notice. Some dinosaurs stacked dry twigs and leaves on top, not only for protection, but also to maintain a certain temperature.
Moms did not leave their nests with eggs for a long time, they were constantly nearby to save the cubs from the attack of various predators. They went away only to eat and drink. Scientists concluded: the sex of future dinosaur cubs depended on temperature in the nest. But in any case, almost always there were more “girls” of “girls”.
At first, newborn babies kept close to their mothers until they became large and strong enough, able to get their own food and run away or defend themselves from enemies.