Which Came First: The Chicken or the Egg? An Evolutionary Perspective on the Origins of Eggs and Modern Birds
Year: 2026
Type: preprint
Abstract: The question of whether the chicken or the egg came first has remained a popularphilosophical and scientific dilemma for centuries. However, evolutionary biologyprovides a scientifically grounded explanation that challenges the traditional inter-pretation of this question. Eggs existed long before the emergence of modern birds,and the evolutionary ancestors of chickens, including non-avian theropod dinosaurs,already possessed egg-laying reproductive strategies.This article examines the evolutionary origins of eggs and the emergence ofmodern birds, exploring the relationship between dinosaur evolution, avian ancestry,and reproductive adaptation. Furthermore, it discusses the distinction between thegeneral concept of an egg and the more specific concept of a chicken egg, addressinghow evolutionary processes complicate the identification of the first true chicken.By examining paleontological and evolutionary evidence, this study argues thatthe egg preceded the chicken by hundreds of millions of years, offering a scientificresolution to one of humanity’s most enduring questions.
Author: Fuertes Oliva, Martín
Institution: Universidad Nacional de Educación a Distancia
Language: English
Subfield: Paleontology
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7225451765