Also a prehistoric behemoth, why have crocodiles survived until now?

The crocodile lives in the deep sea, and the environment it is in is relatively good, it has not been attacked by all kinds of attacks, and its survivability is also relatively strong, so it can survive until now.

Because the metabolic rate of crocodiles is relatively low, crocodiles have to eat some organisms to survive, and crocodiles can adapt to any living environment.

Mainly because crocodiles have always lived underwater, and crocodiles do not have any damage to us humans, and are generally far away from our human lives, so they can live until now, and they are also adapted to the current living environment.

Because the vitality of crocodiles is particularly tenacious, and crocodiles are also easy to adapt to the living environment, so they can always survive.

Because crocodiles are mainly distributed in swamps, lakes, rivers and mountain streams and other humid areas, for large carnivores, it is difficult to obtain sufficient food in this environment, and even if there is sufficient food, it is often discontinuous, and during this period, crocodiles have evolved a unique ability - extremely low metabolic rate, crocodiles themselves are a temperature-changing reptiles, which means that they only need less energy to maintain their physiology, and on this basis, a very low metabolic rate, It gives the crocodile a strong anti-starvation ability.

Crocodiles have now adapted to the development of the earth and have evolved, so they have been able to live until now.

When it comes to prehistoric monsters, our first reaction must be dinosaurs, although dinosaurs became extinct at a very early age, their size and hunting ability are very huge, and they have an absolute position in the animal kingdom. So do you know that there were crocodiles in animals during the same period, but the dinosaurs have long been extinct, why have crocodiles survived until now?

In fact, the crocodile is also known as one of the oldest living fossils on the earth, so it is also an endangered animal, and even the Chinese crocodile is also called the Chinese crocodile, which is listed as a first-class protected animal in China. Many people may think that we can often see crocodiles in zoos, why are they endangered, but because they are endangered and protected animals, in zoos, crocodiles are also bred for their numbers. So when the dinosaurs went extinct, in fact, most of the animals on the earth were already extinct, and only a small part survived.

The crocodile is also a part of it, so it was more than 200 million years ago, in fact, it was in the same era as the dinosaurs, and he was able to survive, and it must be because he has a certain survival advantage and the ability to adapt to the environment.

But the crocodile has survived to this day because it is an amphibian. Because in the period of dinosaurs, dinosaurs can be said to dominate the animal kingdom, its size is very large, and it has a strong hunting ability, and its biting ability is also very strong, so in the animal kingdom, dinosaurs are actually an absolute overlord. Therefore, compared with dinosaurs, crocodiles are also very small, and they belong to reptiles, and there is no threat to dinosaurs, so crocodiles are still amphibians.

It can survive both in the water and on land, which also brings him a great advantage in adapting to the environment. They are able to adapt to the environment in the process of biological evolution, so it is also the reason why they have survived to this day.

This is because you have a wrong understanding of the evolution of species.

Modern crocodiles, like the latest species that have evolved over more than a billion years, belong to the pseudocrocodile class like dinosaurs, and the two share a common ancestor. Although crocodiles and dinosaurs diverged at the same time, the morphology of crocodiles you see now was almost nonexistent at that time, first of all, the common ancestor of crocodiles and dinosaurs was similar to the earliest crocodile base group, the Pike crocodile, which focused on mobility and could run on two legs, so in the Permian sauropids began to overshoot the Archidium (that is, our ancestors, yes, mammals and other beasts evolved an era earlier than dinosaur crocodiles, and even at that time in addition to not being able to suckle, are not much different from the modern animal type), the crocodiles with upright quadruped running and bipedal running and even the same gait as horses are the mainstream, and there are many grass-eating species, which are no different from dinosaurs at first glance, and these bodies are precisely because of the convergence evolution of the dinosaur ecological niche that is consistent with the later dinosaurs, and these crocodiles disappeared in the long river of history with the rise of dinosaurs, under the premise of the same mobility, the body competition is not more than the dinosaurs with air osteogenesis and advanced airbag systems. The body shape of the crocodile you see now is actually the body size of the freshwater ionized vertebrates (also known as amphibians) that dominated the rivers in the Early Permian, and in the Permian mass extinction event, the freshwater ecology and intertidal zone completely collapsed, and the giant newt that went one step earlier was completely extinct, and the ecological niche gap created was filled by the surviving crocodiles, so the body evolution of this aquatic crocodile is almost exactly the same as that of the giant salamanders of the previous generation.

The extinction event at the end of the Cretaceous period mainly affected the ecology of the ground and above and the ocean, and the species in the humus layer, underground, freshwater and intertidal zone survived, so the crocodiles that were suppressed by dinosaurs and sea crawlers to lie flat survived by mistake, due to the high degree of specialization, lost the diversity of evolution, and the dragons and beasts with better congenital conditions than it fought in the Cenozoic. The crocodile, whose status is like Afghanistan in the gap between the United States and the Soviet Union, will never have a chance to enter other ecological niches (and the earlier "giant crocodile" giant freshwater ionized vertebrates have long since retreated to the edge of the ecology and become sticky and slippery slippery amphibians, basically Babylon buried underground-I can only learn that the ancestors were so wide in the topic).

Just as the dinosaurs you can see now are only birds of the Velociraptor branch, and the only mammals you can see are mammals, everyone is the only survivor of the modern evolutionary branch after the mass extinction, who told whom about prehistory?

Moreover, if it is really older, the evolution of mammalian characteristics in the Prepermian is much earlier than the evolution of the flat crocodile in the Jurassic, and the characteristics of prehistory and Erha are much earlier than that of crocodiles.

Because crocodiles' requirements for the living environment are not particularly high, the size of crocodiles is very large, and crocodiles can change with the environment, so they can live until now.

Because crocodiles have a strong ability to resist hunger, they can carry through difficult days, and there is no problem for crocodiles to not eat for a long time.

Because this animal has a strong ability to resist hunger and is particularly adaptable, it has been able to survive until now.

No. Crocodiles are not extinct.

The crocodile is a carnivorous oviparous vertebrate reptile that is the oldest reptile of the same age as the dinosaurs more than 200 million years ago, and one of the most primitive animals living to date. Crocodiles survive and thrive because of their strong vitality, becoming one of the oldest living "living fossils" on Earth.

There are still many varieties of crocodiles in the world at the moment. For example: Nile crocodile, Gulf crocodile, Siamese crocodile and many more.

How is it possible if not? Crocodiles are one of the most common amphibians, and there are wild Chinese alligators in our country, as well as Asian alligators, all of which are real.

It is said that crocodiles have lived on the earth for more than 200 million years because the earliest crocodiles were first seen in the Triassic, but this statement is actually not very accurate. Because in the long history of evolution, living things and their species are a continuous evolutionary process. The oldest protocrodiles are very similar to the allotted lizard, and it was not until the beginning of the Cretaceous period (67 million years ago) that there was a true crocodile suborder.

There are 3 families of true crocodiles: the crocodile family, the snout beak is short and broad, and there is no clear boundary with the posterior segment of the skull. When the mouth is closed, the mandibular dentition is on the inside of the jaw dentition.

The fourth tooth of the lower jaw is enlarged, and the bite of the upper jaw is a hole. For example, the Mihe ray in North America and the Chinese ray (Chinese crocodile) in the Yangtze River; Crocodile family, snout beak short and broad, maxillary and mandibular dentition staggered and incised, the fourth tooth of the lower jaw is large, and the bite of the upper jaw is a depression. There are 11 species of crocodiles, which are widely distributed in the tropics; The ichthyvorous crocodile family has a narrow beak and is obviously different from the posterior segment of the skull, and there is only one species of Ganges fish-eating crocodile in India.

The current fossilized prehistoric crocodile is the 40-million-year-old mekosuchinae crocodile group. At that time, the climate changed abruptly, and the Australian plate and the Antarctic plate also broke off, "parting ways" with each other, and the Australian plate drifted northward, so the climate of the Australian plate near the equator gradually warmed, and a large number of rainforest areas appeared, and crocodiles suitable for rainforest life bred in large numbers. Since then, the crocodile population has evolved into different species of crocodiles.

Looking at the fossils of the mekosuchinae crocodile, the researchers found that the prehistoric crocodile had sharper side teeth than modern crocodiles, and at the same time, the mandible also produced some extra muscles, so it can be inferred that the prehistoric crocodile was more aggressive than the modern crocodile and had more capital when trapping prey. If the two are "able to live together", I am afraid that modern crocodiles do not have much capital to compete with prehistoric crocodiles for food.

As for what abilities crocodiles have survived on the earth for more than 200 million years, I am afraid it is difficult to say. As we all know, the Cretaceous period was an era of reptiles and gymnosperms from their extreme prosperity to decline, and many species, including the dinosaurs, the rulers of the earth at that time, died out one after another, and most species no longer appeared. Also as a carnivore, as large as the ferocious Tyrannosaurus rex, as small as the terrifying microraptor, there is no trace of it.

The crocodile, as a reptilian eye, miraculously survives tenaciously, which may have something to do with its predatory habits. The crocodile is sluggish, so it is unable to track and chase fast-moving targets, and instead has a very strategic and stealthy predatory habit. Under the conditions of extreme food shortage during the glacial period, the crocodile escaped extinction by luck due to its low exercise and low physical exertion of hunting physical strength. And those ferocious carnivores, although they try their best to run, because the food they obtain cannot meet their energy consumption, and in the end they still cannot escape the fate of extinction, we can only say that it is fate.

Since the first sighting of crocodiles in the Triassic, the morphology of crocodiles has changed relatively little, so the existing crocodiles can be called living fossils - this is also a good example of the strong adaptability of crocodiles' living habits.

There are two reasons, one is body size.

The ancestors of modern crocodiles were very small in the Cretaceous period, the giant crocodiles of the Mesozoic era were not the ancestors of modern crocodiles, and the mass extinction of the late Cretaceous period had a significant feature, large organisms were all extinct, and those who survived were smaller creatures.

Second, the higher the status in the food chain, the more fierce the competition, the more frequent the replacement of species, and the dinosaurs are in this position, so the greater the competitive pressure. Although the crocodile is also a predator, it uses ambushes and predators in lakes and rivers, while mammalian predators run fast on land to hunt, and the two sides are not enough to compete, and some early terrestrial crocodiles lose the competition with mammals and become extinct early. Now all that remains is amphibian crocodiles.

The conclusion is that the extant reptiles are, firstly, small in size, at least in the event of mass extinction, and secondly, occupy a relatively low position in the food chain.

Sharks are more than 500 million years old, why are dinosaurs extinct, but not yet?

Natural selection, survival of the fittest!

Because crocodiles are small and not stupid.