"Which came first, the chicken or the egg" was deeply discussed by Socrates, a great ancient Greek philosopher, in ancient times, but he argued endlessly with other philosophers until Europe in the16th century. Coincidentally, Mencius, a thinker and master of Confucianism in China, also thought about this question, and later Mencius also discussed it with his disciples, but there was still no answer. Until the great French biologist Darwin's Origin of Species came out. Only in this way can we give an accurate answer to the question "which came first, the chicken or the egg": Darwin believes that according to the evolutionary derivative structure of natural organisms, the chicken precedes the egg, that is, the mother (chicken refers to the mother) precedes the son (egg refers to the son). So, where did the chicken come from? In fact, all birds (including chickens, ducks, geese and other poultry) are produced by the long-term evolution of the young birds hatched from the eggs of Archaeopteryx/kloc-0.0 billion years ago. Archaeopteryx evolved from the larvae hatched from the eggs of primitive ancient reptiles in more distant times. Primitive ancient reptiles were formed by the long-term evolution of young fish eggs produced by older total fin fish eggs. The initial evolution of life is like this. On the surface, although "egg" is the beginning of all animal life, it is not the origin of all new animal varieties. Everything in the world changes itself through environmental variation (that is to say, "chicken comes before egg" conforms to the changing law of nature itself). Life forms that never "self-design" animal life first (such as eggs before chickens). The question "which came first, the chicken or the egg" has been debated for a long time, and there has been no clear answer. In fact, eggs appeared much earlier than chickens, because reptiles appeared as early as the Permian period 280 million years ago. Reptiles (such as crocodiles and dinosaurs) all laid eggs, while birds appeared in the Jurassic period1.800 million years ago, and chickens appeared later. However, regarding the question of "which came first, the chicken or the egg", we actually asked who came first.

Chickens lay eggs, and eggs hatch chickens. If you say that chickens appeared first, then "how can you hatch without laying hens"? If there is an egg first, you will encounter the problem of "who laid the egg without the chicken", which is really at a loss.

According to the viewpoint of evolution, there is no question of who comes first and who comes later in chickens and eggs. As a species of birds, chickens are differentiated from primitive birds, and eggs are fertilized eggs of chickens (eggs that can breed chickens). In the long process of the formation of this species, chicken has always been a bridge between generations in the evolution of primitive birds-chicken. There are three factors in the process of chicken formation: mutation, heredity and natural selection. "Chicken" lays eggs (it can't be called chicken in primitive times), and eggs lay "chicken". The two generations are not exactly the same, and the offspring born to the same parent are always different. A "chicken" can lay many eggs, but not all eggs can eventually become adult chickens. In struggle for existence, individuals with favorable mutation get the best chance to save themselves, and the advantages and disadvantages are determined by nature, and the formation of chickens is precisely because nature gradually retains their characteristics of being good at running. It is different from primitive birds because of its variation characteristics such as more ground activities and poor flight ability. Obviously, heredity plays a role in maintaining and consolidating variation, and variation is accumulated through heredity.

After a long-term and generation-by-generation process from "chicken" to "egg" and from egg to "chicken", under the action of natural selection, the variation of species is directionally accumulated, which leads to the differentiation of species and the formation of new species, and the "chicken" gradually evolves, so does the egg. This is a process of millions of years, and the order in which "chicken" and "egg" appear must be easy to distinguish.