What Came First?
Whatever criteria one chooses, an animal nearly identical to the modern chicken i.
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- The first eggs.
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The egg—laid by a bird that was not a chicken. It has been suggested that the actions of a protein found in modern chicken eggs may make the answer different.
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Chickens produce a protein, ovocleidin OC , that is expressed in the uterus and causes the formation of the thickened calcium carbonate shell around modern chicken eggs. Because OC is expressed by the hen and not the egg, the bird in which the protein first arose, though having hatched from a non-reinforced egg, would then have laid the first egg having such a reinforced shell: From Wikipedia, the free encyclopedia.
This article is about the philosophical dilemma. For the dish combining both chicken meat and eggs, see oyakodon. The Demiurge in Ancient Thought. A Brief History of the Paradox: Philosophy and the Labyrinths of the Mind.
A few years ago a group of scientists did write about how a particular protein required for chicken egg shell formation was only found in chicken ovaries. Science can help us find the answer. The milk, of course! Send us your question at history time. See if students can name any of the time periods. This page was last edited on 6 December , at Then there was the Cambrian Explosion!
Which Came First, the Chicken or the Egg? That's unlike, say, crocodiles, which lay all their eggs at once, and more like birds, which lay one egg at a time. The ancestors of crocodiles gave rise to dinosaurs and later on, birds. As if figuring out the chicken-egg puzzle weren't enough, the researchers also have another objective: It's entirely possible, but again these types of nests from small meat-eating dinosaurs are fairly rare.
The first chickens
Previously she was an assistant editor at Scholastic's Science World magazine. Jeanna has an English degree from Salisbury University, a Master's degree in biogeochemistry and environmental sciences from the University of Maryland, and a science journalism degree from New York University.
The jury is still out over whether the chicken or egg came first. But turns out dinosaurs were laying bird-like eggs long before chickens roamed Earth. Egg-laying behaviors The analysis of the nest, detailed in the latest issue of the journal Palaeontology , provides paleontologists with information about egg-laying in this particular dinosaur and others, along with the evolution of various egg-laying behaviors, Therrien said.
Technically speaking, an egg is simply the membrane-bound vessel inside which an embryo can grow and develop until it can survive on its own.
At some point, a different kind of egg began to evolve, which had three extra membranes inside: Each membrane has a slightly different function but the addition of all these extra layers provided a conveniently enclosed, all-in-one life support system: The extra fluids encased in the amnion, plus the tough outer shell, provide extra protection too. Amniotic eggs were a big deal. They opened up a whole new world of opportunities for land-based egg-laying locations, and the extra membranes paved the way for bigger and mostly better eggs.
Our best guess is that the last common ancestor of both tetrapods four-limbed animals with a backbone and the amniotes four-limbed animals with a backbone that lay eggs with all those extra layers lived around million years ago, though some sources put the first amniote species as living closer to million years ago.
Now You Know: Which Came First, the Chicken or the Egg?
This leaves us with another eggsellent question: The very first chicken in existence would have been the result of a genetic mutation or mutations taking place in a zygote produced by two almost-chickens or proto-chickens. This means two proto-chickens mated, combining their DNA together to form the very first cell of the very first chicken. Somewhere along the line, genetic mutations occurred in that very first cell, and those mutations copied themselves into every other body cell as the chicken embryo grew. The first true chicken.