This age-old question has intrigued philosophers, scientists, and casual thinkers alike, sparking debates across various fields, including biology, anthropology, and philosophy. To address this question, it’s important to understand the evolutionary process and the role eggs have played over millions of years.
Modern birds, including chickens, are descendants of theropod dinosaurs. Eggs, as a reproductive mechanism, existed long before birds came into being. Reptiles and other vertebrates were laying eggs over 300 million years ago, far preceding the evolution of the first birds. Thus, at a fundamental level, the egg in general predates the chicken.
If we specifically consider the domesticated chicken, Gallus gallus domesticus, it’s a result of evolutionary changes in its wild ancestor, the red junglefowl. During this evolutionary process, a genetic mutation in the embryo likely led to the first true chicken. This embryo would have developed inside an egg laid by a bird not quite a chicken—a proto-chicken. Hence, from an evolutionary perspective, the egg containing the first chicken came before the chicken itself.
Adding a philosophical angle, the question explores causality and sequences of events, providing a foundation for discussions about origins, both in biological terms and broader existential ones. However, from a strictly biological standpoint, the egg as a structure existed long before chickens, and the specific egg giving rise to the first chicken laid the groundwork for the species as it is known today.
