Check out the egg Inception, or egg-within-an-egg phenomenon, and find out what causes it
YouTuber Sean Wilson filmed himself while breaking the biggest egg in the world, or at least the biggest one he has ever seen.The monster-egg weighs 6.25 ounces (177 g) and it is visibly larger than regular ones, which can be seen on the man's counter.
The amazing thing about this video, though, is not the size of that egg, but the fact that Wilson got a big surprise when he broke it. He expected to find at least 2 yolks inside, but ended up discovering a second egg. In the end, he did get his 2 yolks.
His find is rather unusual, but it's not unheard of. The Telegraph reported about a similar example back in 2009.
As the egg develops, and is almost ready to be laid, it can be pushed back in, into another egg, which is what causes the egg Inception, or egg-within-an-egg phenomenon. A visual explanation is posted below.