Do mammals have to be homeotherms

In nature, mammals and birds are homeotherms, and they are more adaptable to climate changes and can regulate their own body temperature than ectotherms. So, do you know where exactly this "special feature" of theirs comes from? Today, let's discuss it together.

Studies have found that the emergence of homeotherms is associated with mass extinctions.

In the process of the evolution of the earth, every once in a while, there will be extinction events, the most serious of which is a total of 5, the closest one to us, occurred 65 million years ago, dinosaurs withdrew from the stage, mammals evolved rapidly, primates appeared, and humans became the new masters of the earth.

When the time goes back further, the mass extinction event before the dinosaurs occurred hundreds of millions of years ago, when the earth was at the turn of the Permian and Triassic periods, whether it was the ocean or the land, life was very rich, but the disaster came quietly, this mass extinction was also the worst on the earth, 96% of the creatures died as a result.

The surviving animals are also not optimistic, because after the catastrophe, it takes a long time for the earth to regain life, in the early Triassic period, the temperature on the earth was very high, and the climate became arid, at this time, among the surviving animals, the synapses and archaeosaurs in the quadrupods, which were the ancestors of the mammals and birds that appeared later, in order to survive, began the evolution of ectotherms to homeotherms, and finally succeeded.

How did homeothermic animals appear?

While studying Triassic survivor fossils, researchers found that with the end of the Fourth Mass Extinction, all the medium- and large-sized quadrupeds that survived on Earth went from an extended state to an upright position, as if overnight.

What are the effects of this change in attitude? In the case of stretching posture, ectotherms are animals with stretching posture, and their limbs are partly sideways, such as reptiles and amphibians.

In the upright state, the limbs are directly under the body, which not only makes it easier to move, but also makes it easier to obtain food, has a faster metabolism, and the body is more adaptable.

Professor Mike Benton, a paleontologist from the University of Bristol in the United Kingdom, said that this short-term change in attitude is the surviving animals in order to better adapt to the changes in the earth's climate, because only by consuming enough food can the body temperature be kept constant.

In addition, researchers also said that although the fourth mass extinction is the most serious mass extinction on the earth, it is an important turning point, because from this mass extinction, the life on the earth has officially changed from the paleontobiota to the modern biota, and the earliest ancestors of many modern organisms also appeared after this mass extinction.

At the same time, the face of the earth has changed, and the prototype of the modern continent has appeared. Hundreds of millions of years ago, the first mammals appeared, but they disappeared until the end of the Cretaceous period, when the dinosaurs became extinct, and finally became familiar to us.

Significance: (1) Viviparity is a mammalian Zen rotten search.

The survival and development of the company provides broad prospects.

2) Viviparity provides protection, nutrition and stable thermostatic development conditions for the developing embryo, so that the adverse effects of external environmental conditions on embryo development are minimized.

3) Feeding young animals with milk is a favorable adaptation for the rapid development and growth of offspring under superior nutritional conditions. Plus mammals.

A variety of well-established protective behaviors for the young, so that the offspring have a higher survival rate than other vertebrates.

Much higher. In association with this, the number of litters in mammals decreased significantly.