The predecessor of mammals was reptiles, when did that start developing?

The earliest mammals.

It's a reptile.

evolved from the order of the Beast Pore. True mammals appeared at the end of the Triassic.

1. A brief description of the evolutionary history of organisms.

In the primeval period of the earth, there was no life on the earth, and it was the first period of the development of the earth's geological sphere. In 3.1 billion years, algae and bacteria appeared on Earth, and 2.9 billion years ago, prokaryotes appeared. 1.9 billion years ago, the living environment appeared, cyanobacteria.

And bacteria roam the world, 1.3 billion years ago green algae appeared. 1.3 billion years ago, plankton and arthropods appeared.

Wait. The Paleozoic era began 600 million years ago, and there were six epochs in this period, with the appearance of lower fishes, paleoamphibians, reptiles. Mesozoic.

It appeared 100 million years ago and ended 67 million years ago, divided into the Triassic and Jurassic periods.

and Cretaceous, the Mesozoic is the age of reptiles, and the earliest primitive reptiles, Archaeopteryx, appeared at the end of the Triassic.

Finally, there is the Cenozoic, which is divided into the Tertiary and Quaternary periods, and humans appeared in the Quaternary.

2. How did the first mammals come about.

Archaeopteryx is known as the earliest and most primitive bird. As for why the earliest mammals? In fact, it is because the characteristics of Archaeopteryx are more inclined to the transition period from reptiles to mammals.

It's about the same size as a crow, but it can only run, not really fly. In other words, the ancestors of Archaeopteryx may have glided between trees and the ground, which is why the offspring began to have feathers in preparation for future flights. Because Archaeopteryx has both characteristics, it is considered to be a transitional period from reptiles to mammals, and of course, it is the first time that modern humans have found evidence from this bird to fill the gap in biological evolution.

3. Mammals.

Modern times are the world of mammals, from the Quaternary period to the present, thousands of species of mammals have diverged. However, among the mammals, only humans were the ones who stood up and started using tools. Humans are the result of both evolutionary and environmental selection.

From ancient times to the present, the absence of any link in the history of evolution may prevent today's human beings from appearing, so thank you and me for surviving in the world today.

Mammals first appeared in the Triassic, which should have begun to develop around the Permian, and by the Quaternary mammals had become the dominant animals on the planet.

Permian time. At this time, reptiles gradually evolved into mammals, and the main characteristics were from oviparity to viviparity, and the female reptile was able to secrete milk; Later, during the mass extinction, mammals survived in large numbers because of their adaptability.

Jurassic to 100 million years ago, evolved a part of the mammal-like, that is, there are common features of mammals and reptiles.

1.Mammals, like birds, are all reptiles that evolved. Mammals are a class of the subphylum Blind Vertebrates, commonly known as mammals.

Mammals are found all over the world and live a variety of lifestyles on land, underground, in the water and in the air. There are three types of nutrition: herbivorous, meat-fed and omnivorous;

2.The earliest mammalian scattered menhir was the Wu giant head found in China. Every tooth in reptiles is the same, while mammalian teeth are divided into different morphologies depending on where they are located in the jaw.

In the animal kingdom, only mammals have three bones in their ears. They evolved from the two jaws of reptiles;

3.Mammalian evolution is done through movement and food chain alterations. The five-toed limbs of primitive mammals, which are suitable for walking on the ground, have evolved into many specialized types as they adapt to different lifestyles, and primitive mammals are mainly omnivores that feed on insects.

Later, due to adaptation to different lifestyles, they evolved into: omnivores, feeding on animals and plants; Herbivores feed on plants; Carnivores feed on animals.

The earliest mammals.

It occurs from the end of the Triassic to the Jurassic.

At first, the most primitive mammals belonged to the oviparous insectivores of the suborder Protozoa. Mesozoic.

Although the mammals have divided into many different groups, they are all relatively small animals.

The Triassic, in fact, is a geological era from 100 million BC to 200 million years ago, it is located between the Permian and Jurassic, is the first epoch of the Mesozoic period, and is the transition period after the disappearance of the Paleozoic biota and the beginning of the formation of modern biota. During the Triassic period, the climate was hot and dry, so the red sand and gravel that we can see were formed.

Mammals and fish, amphibians and reptiles of the time.

In contrast, they grow hair, which allows them to regulate their body temperature in order to adapt to different climate changes. The process of incubation of mammalian eggs is carried out in the mother's body, so they exhibit viviparous characteristics. Another important characteristic of mammals is their familial nature, as their young are cared for as well as "educated".

Larvae, they learn from their parents' generation. And then pass that experience on from generation to generation.

The fact that the ancestors of mammals began their training in viviparity and nursing in such difficult circumstances was of great significance.

The earliest mammals appeared in the Triassic, and the most dominant creatures of that period were reptiles, the most famous of which were reptiles. Mesozoic mammal fossils were first found in strata of the Late Triassic. In the Jurassic and Cretaceous.

Stratigraphy, the whole world except South America.

and fossils have been found outside Australia.

The body structure of mammals is more complex, and there is a brain structure that distinguishes it from other taxa.

Thermostatic systems as well as circulatory systems, and most of them are viviparous.

Advanced properties of mammals:

1.Highly developed nervous system.

and the senses, able to coordinate complex functional activities and adapt to changing living conditions.

2.Constant body temperature, perfect blood circulation system.

as well as body surface coat and other thermoregulators with thermal insulation properties.

It provides a stable internal environment and reduces dependence on the external environment.

3.Oral chewing and digestion greatly improve the ability to extract energy.

4.Lactation and viviparity: Long-term lactation and nurturing of offspring by females improves the survival rate of offspring and helps offspring learn and adapt skills.

5.Ability to move quickly on land.

With the exception of the fifth monopore mammal, all mammals produce offspring directly, and most have teeth adapted to their environment.