ickplantA cassowary egg (left) next to an emu egg (right). They are some of the largest bird eggs on the planet.
stupidcaseyFun fact, ostrich eggs are nearing The largest land eggs can physically get, so even the dinosaurs didn’t have much bigger eggs.
Captain AggravatedWhat’s the limiting factor?
If I had to guess it’d be the ability for oxygen to diffuse through the shell and reach the embryo?
I got curious and your assumption is correct for one of the limiting factors.
Here is what I found:
- The shell must be strong enough to support the egg’s weight and protect the embryo, but thin enough for the chick to break through when hatching.
- As size increases, the weight grows cubically (volume), but shell strength only increases quadratically (surface area), so there’s a point where the shell would have to be too thick to hatch from.
- The distance from the shell to the center increases.
- Oxygen diffusion becomes inefficient, and the embryo could suffocate.
- Larger eggs are harder to keep at a uniform temperature.
- Birds incubating the eggs would need to generate and distribute more heat, which is physically demanding.
Didn’t think I would find egg facts so interesting… Cool!
That’s eggcelent and I’m eggstatic that you enjoyed. Come back next Easter for more egg facts.
Benedict!
I don’t think I’m doing this right.
AnUnusualRelicI never even considered that but it makes total sense. Thanks for the great post.
No problem. I get curious myself so figure it nice to share with people that don’t tell me they’re not interested in useless facts.
Appreciate the share, that’s awesome info
What’s your sources? Begging your pardon, that looks like a perfectly standard GPT answer.
MaxI think point two may be wrong. The strength of a shell should be proportional to its thickness, which would scale linearly with its size (assuming the shell got thicker in proportion to the size). There’s definitely a point where a self supporting egg requires very thick shells like you said, but the scaling law you gave uses the wrong change.