Eggs come from chickens and chickens come from eggs: that’s the basis of this ancient riddle. But eggs – which are just female sex cells – evolved more than a billion years ago, whereas chickens have been around for just 10,000 years. So the riddle is easily solved…or is it?.
Taken at face value, there is no doubt that the egg came before the chicken. Eggs are the hard-shelled balls that birds lay from which their chicks hatch, unless we eat them first. But all sexually reproducing species make eggs (the specialised female sex cells). That’s 99. 99 per cent of all eukaryotic life – meaning organisms that have cells with a nucleus, so all animals and plants, and everything but the simplest life forms.
We don’t know for sure when sex evolved but it could have been as much as 2 billion years ago, and certainly more than 1 billion. Even the special kind of eggs that birds lay, with their tough shells, have been around for more than 300 million years.
As for chickens, they came into being much later. Because they are domesticated animals, they evolved by humans choosing the least aggressive wild birds and letting them breed. This seems to have happened in several places independently, starting around 10,000 years ago.
The wild ancestor of chickens is generally agreed to be a tropical bird still living in the forests of Southeast Asia called the red junglefowl – with other junglefowl species possibly adding to the genetic mix. From these origins, humans have carried chickens around the world over the past two millennia or more.
So, eggs dramatically predate chickens. But to be fair to the spirit of the riddle, we should also consider whether a chicken’s egg predates a chicken. As humans consistently chose the tamest red junglefowls and bred them together, the genetic makeup of the resulting birds will have shifted. At some stage during this domestication process the red junglefowl (Gallus gallus) evolved into a new subspecies, Gallus gallus domesticus, AKA the chicken.
In practice, it is impossible to pinpoint the moment when this happened. But in theory, at some point two junglefowl bred and their offspring was genetically different enough from the species of its parents to be classified as a chicken. This chicken would have developed within a junglefowl egg and only produced the very first chicken’s egg on reaching maturity. Looked at this way, the chicken came first.
“Which came first, the chicken or the egg?” is an old question that has stumped philosophers, scientists, and thinkers for hundreds of years. At first glance, it looks like there is no way out of this paradox: chickens hatch from eggs, but chickens lay eggs. But thanks to modern evolutionary biology, we can find out for sure where the chicken and egg came from by going back in time.
We’ll look at the scientific evidence and evolutionary history behind the chicken and egg to solve this age-old puzzle.
A Brief History of the Chicken and Egg Debate
The “chicken or egg” question is an old philosophical puzzle about the problem of origins and the first cause. Greek thinkers like Plato and Aristotle thought about how the chicken and egg cycle could go on forever. Which one was the ultimate origin point?.
Later, Christian theology came up with the answer: God made chickens first in the Bible’s story of creation. But during the Enlightenment, philosophers brought up the issue again by questioning Biblical explanations. The paradox was pondered anew from evolutionary perspectives.
So this innocuous poultry puzzle has vexed some of history’s greatest thinkers! But modern genetics provides some concrete solutions,
The Evolutionary History of the Egg
To answer which came first, we need to define what type of egg we’re talking about. In the broadest evolutionary sense, the egg definitely preceded the chicken.
Eggs in some form have been around for hundreds of millions of years before anything resembling a modern chicken appeared. Amphibian eggs transitioned into amniotic eggs with protective shells and nutrient-rich yolks approximately 312 million years ago. This evolutionary innovation enabled reptiles and later birds to reproduce on land rather than remaining tied to water like amphibians.
Dinosaurs started laying amniotic eggs around 200 million years ago. So the first calcified eggshells emerged well before the age of birds. Different vertebrates including ancient reptiles, dinosaurs and eventually proto-chickens continued to lay eggs through the eras.
Modern chickens descended from red junglefowl around 8,000 years ago. Therefore, chickens evolutionarily followed eggs by hundreds of millions of years. Case closed? Not quite…
Defining the Chicken Egg
The above history traces the broad timeline of shelled eggs. But what if we’re asking specifically about chicken eggs laid by chickens?
Here’s where it gets trickier. The chicken egg containing the first modern chicken would have genetically differed from its junglefowl parent. After hatching, this primordial chicken would have grown up to lay the first official chicken egg.
So in this sense, the egg housing the first modern chicken came after the chicken, even though it was laid by a proto-chicken ancestor. The chicken genetically arrived before the chicken egg, but the chicken egg still came before the adult chicken!
The Fuzzy Boundaries of Chicken Evolution
Tracing that definitive first chicken and chicken egg is difficult, however, because the domestication of chickens from junglefowl was a messy evolutionary process spanning thousands of years. Chickens interbred with other fowl species at times, blurring genetic lines.
The origins of modern chickens were also geographically diverse, with different groups domesticating junglefowl in Asia, India, and Oceania independently. With so many branches on the chicken family tree, it’s hard to point to the first modern chicken or the first pure chicken egg.
Regardless of the uncertainties, it’s clear the chicken/egg puzzle has a different answer depending on whether we’re talking about eggs in general or specifically chicken eggs. Modern chickens evolved later than the general amniotic egg, but the chicken egg harboring the first modern chicken still came before that chicken fully hatched.
Cracking Open the Mystery
While chickens and eggs will likely always be intertwined in this paradoxical cycle, evolutionary biology has given us some definitive answers to the classic question. And although we may never know the exact first chicken or chicken egg, unscrambling their evolutionary history is fascinating.
The puzzle contains layers of biological complexity and forces us to question definitions. A deceptively simple poultry riddle has stumped great minds for centuries. But step-by-step, science is illuminating the origins of the chicken and egg bit by bit to crack open this enduring mystery.
So next time you eat an omelet or some chicken nuggets, remember the epic evolutionary journey that brought you that protein packed meal!
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Eggs come from chickens and chickens come from eggs: that’s the basis of this ancient riddle. But eggs – which are just female sex cells – evolved more than a billion years ago, whereas chickens have been around for just 10,000 years. So the riddle is easily solved…or is it?.
Taken at face value, there is no doubt that the egg came before the chicken. We tend to think of eggs as the shelled orbs laid by birds from which their chicks hatch – unless we eat them first. But all sexually reproducing species make eggs (the specialised female sex cells). That’s 99.99 per cent of all eukaryotic life – meaning organisms that have cells with a nucleus, so all animals and plants, and everything but the simplest life forms.
We don’t know for sure when sex evolved but it could have been as much as 2 billion years ago, and certainly more than 1 billion. Even the specialised sort of eggs laid by birds, with their tough outer membrane, evolved more than 300 million years ago.
As for chickens, they came into being much later. They are domesticated animals, so evolved as the result of humans purposefully selecting the least aggressive wild birds and letting them breed. This seems to have happened in several places independently, starting around 10,000 years ago.
The wild ancestor of chickens is generally agreed to be a tropical bird still living in the forests of Southeast Asia called the red junglefowl – with other junglefowl species possibly adding to the genetic mix. From these origins, humans have carried chickens around the world over the past two millennia or more.
So, eggs dramatically predate chickens. But to be fair to the spirit of the riddle, we should also consider whether a chicken’s egg predates a chicken. People picked the tamest red junglefowls and bred them together over and over again, which transformed the birds’ genes. At some stage during this domestication process the red junglefowl (Gallus gallus) evolved into a new subspecies, Gallus gallus domesticus, AKA the chicken.
In practice, it is impossible to pinpoint the moment when this happened. But in theory, at some point two junglefowl bred and their offspring was genetically different enough from the species of its parents to be classified as a chicken. This chicken would have grown inside a junglefowl egg and would have laid its first egg when it was fully grown. Looked at this way, the chicken came first.
Which Came First – The Chicken or the Egg?
FAQ
Is there an answer to the chicken or the egg?
It’s pretty safe to say that the egg came first, because if there had been no egg, there would have been no chicken. Chickens are birds, and we know that birds evolved from reptiles, so we can say that the first bird hatched from an egg that was laid by a reptile that was very similar to, but not quite, a bird itself.
Did the chicken or the egg first?
But eggs – which are just female sex cells – evolved more than a billion years ago, whereas chickens have been around for just 10,000 years.
Did the chicken or the egg came first in the Bible?
The Biblical account of God creating birds tells us the chicken came before the egg. “Then God said, ‘Let the waters teem with swarms of living creatures, and let birds fly above the earth in the open expanse of the heavens.
Who came first, the chicken or the egg in Islam?
It is stated in the sacred books that the hen existed first. These books teach that animals were created at the beginning of the world; hence the hen did not come from the egg but from nothing. ”.