in World Egg Day The Mail Online website asked evolution experts for their opinions on this classic puzzle.
They claim that although eggs evolved millions of years before chickens, this does not necessarily mean that “Chicken egg“She came first.
What is an egg?
I found it The egg For nearly as long as all life on Earth, with the exception of mammals, almost all animal species lay eggs.
Jules Howard, a zoology reporter and author of a book on the evolution of eggs called Infinite Life, told Mail Online: “Eggs are the preferred method of evolution and the transmission of genes to subsequent generations in time.”
The development of the first eggs may be closely linked to the birth of life as we know it.
Before this development, organisms reproduced through a form of cloning – creating a genetically identical population that was highly vulnerable to viruses and parasites.
“Without sex, and therefore eggs, we think viruses are more likely to destroy individuals which means they die more often,” Howard explained.
There is no doubt that ancient eggs were very different from what we consider eggs today, and could have been laid by jellyfish or worm-like creatures since the dawn of time.
According to Howard, 600 million years ago, fossils from China indicate that eggs were very small, no thicker than a human hair.
“These eggs were transported across the oceans, as if in milky clouds. There were no nests. These eggs were pumped into the water and settled on the sea floor,” he said.
The egg comes before the chicken
Since this was hundreds of millions of years ago before life even ventured out onto Earth, it’s safe to say that the egg came before… Chicken.
For the majority of us who think of eggs as hard-shelled things that can be opened, this may not be a very satisfactory answer.
Unfortunately for anyone still betting on chickens, the first hard-shelled egg appeared much earlier than the chicken.
“If you include them, in reference to eggs as a whole, then the answer is definitely eggs,” Dr Elaine Mather, a paleontologist from Flinders University who specializes in ancient birds, told MailOnline.
What is chicken?
Descending Chicken The first domestic species came from a species of red jungle fowl called Gallus gallus, which evolved about 50 million years ago.
Researchers believe that when humans began clearing forest areas to grow rice and millet, birds from the forest began congregating on the edges of the new fields.
Over time, as the birds adapted to their new neighbors, they became more accustomed to humans and less territorial, and began raising larger groups of chicks.
Eventually, this transformed some of the wild junglefowl into a new species that became known as the domesticated chicken or Gallus gallus domesticus.
Stay, researchers believe the first true domestic chicken appeared about 10,000 years ago.
However, subsequent analysis reveals that many of the supposed “chicken” specimens actually belonged to… Wild birds Others like ducks.
More recent studies indicate that humans in Southeast Asia first domesticated these birds between 1650 BC and 1250 BC.
At most, this means the chicken is about 3,500 years old.
Which came first, the dinosaur or the egg?
While the chicken is only a few thousand years old, the egg, on the other hand, dates back millions of years Dinosaurs.
Dr Mathers says: “The first egg laid on Earth probably came later in the world Carboniferous era “Between 358 and 298 million years ago, it was laid down by early reptiles.”
These eggs were likely to have smooth shells like the eggs of modern reptiles such as snakes.
Mathers explains that the first hard-shelled egg appeared during the early Jurassic period, and was laid by dinosaurs.
Fossilized eggs were found laid by long-necked dinosaurs, a family that includes Brontosaurus and Diplodocus, dating back 195 million years.
This egg would have looked more like the eggs we recognize from many birds and lizards today.
Last year, scientists discovered a massive dinosaur hatchery containing 91 titanosaur nests and 256 eggs, showing that these giant creatures nested together just like birds.
Even if we limited our search for eggs to only those laid by birds, chickens would still lose out by more than 100 million years.
About 150 million years ago, Archeopteryx appeared, the first bird to evolve from dinosaurs.
Likewise, the oldest confirmed fossil egg believed to have been laid by a bird is about 127 million years old, dating to the Early Cretaceous period.
So, in evolutionary terms, the egg definitely came before the chicken.
The argument in favor of chicken
While this may seem like a chicken jab, that’s only one way to interpret the question.
“Depending on how you interpret the question, both answers could be correct,” Mathers says.
Instead of asking whether it was the chicken or the egg that evolved first, the more classic version of the question is to ask whether the “chicken or the chicken egg” came first.
The obvious puzzle is that we might think that chickens can only hatch from a chicken egg, which of course can only be laid by another chicken.
However, thanks to our modern understanding of evolution, we know that this is not the case.
Species like chickens are not fixed masses that exist forever but are temporary structures thrown together by turbulent evolutionary currents.
This means that there was a moment when a group of wild birds stopped being forest birds and started being chickens.
“The first true chicken hatched from an egg laid by partially domesticated red jungle fowl,” says Dr. Mather.
In other words, the first true hen must have hatched before any true chicken eggs were laid.
“If the question were interpreted as referring to chicken eggs, the answer would be a chicken,” Dr. Mathers concludes.
