This is an old and interesting question, thinking about the origin and evolution of life. First, let's dive into the question.
The beginning of the story takes us back to the distant age of dinosaurs. At that time, there were no chickens on the earth, only a creature called the "protochicken". Raw chickens weren't what we see chickens now, but they were the ancestors of modern chickens. Raw chickens start laying eggs at some point, and these eggs hatch into new original chickens. Over time, the genes of these protochickens have mutated, and their body morphology and habits have gradually changed.
With the changes in the earth's environment and the evolution of organisms, the original chickens gradually adapted to the new environment, and their body forms and habits gradually changed. At some point, the genes of these protochickens mutated, and the eggs they laid began to hatch into organisms that were different from the original chickens. These organisms have a higher growth rate and greater adaptability, and they are gradually becoming the dominant organisms on the planet. These creatures are what we now call "chickens."
So, now back to the beginning of the question: came first, the chicken or the egg? As we can see from the above story, it was the proto-chicken that laid the eggs first, and these eggs hatched into new creatures that evolved into what we now call "chickens" over time and genetic mutations. Therefore, we can conclude that first there are eggs, then there are chickens.
This question also makes us think about the process of the evolution of life and the power of natural selection. In the process of evolution, life is constantly adapting to changes in the environment, and genetic variation is an important factor promoting the evolution of life. Natural selection, on the other hand, is a process of selection that allows organisms that adapt to their environment to survive and reproduce.