The question of which came first, the chicken or the egg, has been a topic of philosophical and scientific debate for centuries. From a biological perspective, it is believed that the egg came first.
The reason for this is that chickens, or more specifically, their ancestors, evolved through a process of gradual genetic changes over millions of years. These changes would have occurred in the reproductive cells of these ancestral birds, which would have eventually led to the formation of a new species, the chicken.
Therefore, the first true chicken would have hatched from an egg that was laid by a slightly different bird, which was not quite a chicken, but was in the process of evolving into one. So, in essence, the egg came first, laid by a bird that was not quite a chicken, but whose offspring eventually evolved into the chicken we know today.