An article from ABC science
If you have a sense of curiosity, you probably like to ask questions. And if you like to cook, and are curious, you might have asked, “Why are eggs egg-shaped?”
First of all, what is the shape of a chicken egg? It’s not round or spherical, like some reptile eggs. It’s not oval either. It’s an asymmetrical mix of oval and tapered, with one end bigger than the other — yup, chicken eggs are an ‘asymmetric tapered oval’.
If eggs were rectangular little boxes, they would be very strong on the corners, but very weak in the middle of the straight walls. (They would also be extremely uncomfortable for the chicken to lay.)
The strongest shape of all is a ball, or sphere. But if you were to push or gently nudge a spherical egg, it would roll away downhill, never to be seen again.
So one reason that eggs have an asymmetric tapered oval shape is that if you nudge them, they’ll come back to you. They’ll sweep out a circle around the pointed end, and come to a stop with the pointed end facing uphill. In fact, the eggs of birds that have their nests on cliffs are more oval than the eggs of birds that nest on the ground. This means the ‘more-oval’ eggs of these cliff-nesting birds will roll in a very tight little circle, and be less likely to roll out of the nest — and off the cliff.
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