Which came first? The chicken or the egg?

It’s an age old question, which ancient philosophers first pondered. Back in Ancient Greece, Aristotle claimed that the chicken and the egg both had always existed and went infinitely back in time. Plutarch, a Greek writer, well known for his philosophical questions, famously pondered whether the hen or the egg came first.

Globe egg by Angelina Todorovic Stanic fliqr

If the chicken was first, how was it born? If it was an egg, what laid it? A question of this type is called a causality dilemma, and there are many of its type.

The Egg Came First:

As silly as this question sounds, there is a scientific answer to it. A science writer at BBC’s Focus magazine, Luis Villazon, put forward a scientifically backed explanation to the question which comes back to good old evolution. Darwin’s theory taught us that all life evolved from common ancestors. Random genetic mutations which occur over time lead to beneficial alterations being preserved in a process known as natural selection.

Over 10,000 years ago in Indonesia, lived the ancestors of the chicken, namely the red junglefowl. When the DNA from the sperm of the male red junglefowl met the ovum of the female jungle fowl it formed a zygote. Small changes and mutations of the DNA of the red jungle fowl led to the creation of the first chicken. The formation of the zygote cell is the place where mutations occur which can lead to the production of a new animal, and the zygote cell is in the egg the egg must have come first.

The Chicken Came First:

As plausible as Luis Villazon’s explanation sounds, it has been refuted by researchers at the universities of Sheffield and Warwick.  These scientists used a super computer to apply a computing tool known called metadynamics to ‘zoom’ in on the egg as it forms. According to these scientists, chicken eggs are formed using a protein found in chicken’s ovaries (ovocledidin-17) which  acts as a catalyst speeding up development of the shell, and is vital for shell production. While these scientists agree that there were other types of birds which also laid eggs which pre-dated chickens, they didn’t necessarily produce their eggs the same way using the same protein. This is the reason chickens form shell (6g per 24h) faster than any other species. Therefore according to this research an egg can only form if it has been inside a chicken.

This research didn’t definitively answer a question which has been asked since Aristotle’s time, but it’s not necessarily what they set out to do. The aim of the research was to understand how chickens make eggshells, which is a fascinating process that can be modelled when designing new materials and processes. The researchers have stated this new technology can be used to develop new and efficient ways of crystallisation, which can be applied to the formation of synthetic bone.

You’re now probably disappointed that you’ve come to the end of this post and don’t have a definitive answer, but I think it’s up for to you to decide which you think came first. If you managed to crack the case lay it on me.

Interested to find out more? These are a really interesting read!