Try to Guess Which Came First, the Chicken or the Egg?

VIVA – Many people ever heard the old riddle, which came first, the chicken or the egg? Throughout history, the question of which came first between chickens and eggs transcends human civilization. The answer to this question can be traced back to ancient times. Most biologists emphatically state that eggs came first. This refers to the basic concept, which is that eggs are just female sex cells.

Meanwhile, other experts see it from an evolutionary point of view. The egg that we know today has a hard shell or an amniotic egg or amniotic is a change in the evolution of the animal world.

"The egg is a significant step in (vertebrate) evolution because it allows the amnion to go further and further from the air," said Koen Stein, a paleontologist at the Royal Belgian Institute of Natural Sciences.

Before the dawn of hard-shelled eggs loaded with nutritious yolks, vertebrates had to rely on bodies of water to reproduce. Most amphibians still face this aquatic limitation — they need to keep their gelatinous eggs moist to survive.

According to research published in the journal Current Biology, birds do not appear in the fossil record from the mid-to late Jurassic, about 165 million to 150 million years ago. But scientists at the Center for Biological Diversity at the University of Texas describe the first shelled eggs evolving long before that, around 325 million years ago.

It means, the egg came well before the chicken, according to Stein. These very first eggs were likely malleable and leathery in texture, much like the eggs laid by today's reptiles and platypuses.

There were plenty of land-based vertebrates laying amniotic eggs in the Carboniferous, Permian, and Triassic periods, but the most famous of these animals are the dinosaurs. Stein has studied some of the earliest known dinosaur eggshells, which come from the early Jurassic period, about 200 million years ago.