The age-old question—Did the egg come first, or the chicken?—actually has a pretty clear answer when we look at it from a scientific perspective. The egg came first. That might sound surprising at first, but it makes sense when you think about how animals evolve. Chickens didn’t just suddenly appear out of nowhere. They are the result of a long chain of gradual changes through evolution. Scientists believe that modern chickens evolved from birds very similar to red junglefowl, wild birds still found in parts of Asia today.
Long before there were chickens, animals like reptiles and ancient birds were already laying eggs. In fact, eggs have been around for hundreds of millions of years—far longer than chickens. The type of egg we’re talking about here called an amniotic egg, first appeared around 340 million years ago. These kinds of eggs allowed animals to lay their eggs on land, which was a huge step in the history of life.
At some point, two birds that were almost—but not quite—chickens mated and laid an egg. Thanks to a small genetic mutation in that egg, the creature that hatched was different enough to be considered the very first chicken. So technically, the egg containing the first chicken came before the chicken itself.
