(Photo : Pixabay/MabelAmber)

Chickens lay eggs one at a time- that's a common knowledge that needs no research. Hence, it is very surprising when a hen lays one big egg with a smaller one inside. This can be seen in a viral TikTok video wherein a massive egg was being opened revealing a shocking surprise to them.

At first, the video shows an egg which is a lot bigger than the usual chicken egg. It weighs 150 grams or 0.3 pounds with a height of 8 centimeters or 3 inches. With the looks of it, it is three times heavier than an average egg.

TikTok user @megss__b was initially surprised by the huge size of the egg. She said that it took all afternoon for their hen to lay. After showing a size comparison with a regular egg, they decided to crack it open.

While opening, she observed that the shell was too thin and was easy to crack. When it finally opened, everyone can be heard screaming upon seeing another egg inside.

Watch the video here:

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Egg Inside An Egg

This surprise egg is actually not that surprising because although rare, things like this can actually happen. While a hen is trying to lay egg one, a counter-peristalsis contraction occurs which pushed it back to the chicken's reproductive system. As a result, this egg is pushed inside a developing egg which then encase it, iFLScience explains.

Like what is seen in the TikTok video, the outer egg (egg two) created a nutritious albumin and yolk. This is the same story with egg one but is much older since it was first cooked up by the hen.

In 2018, a hen named Bell was reported to lay extra large eggs with another one inside it. Grégoy Bédécarrats, a professor at the University of Guelph's Department of Animal Biosciences, told CBC that it is difficult to track how frequent a hen can lay eggs like this. He added that one factor affecting this is the chicken's genetics.

Weird Chicken Eggs

Aside from a giant egg with another egg inside it, there are other quirks that can happen. Others see eggs without a shell or a soft shell. There are also eggs with two or three yolks inside.

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