Human eggs are about the largest single cell humans produce, about 0.1mm in diameter.
But human eggs don’t provide nutrients to the fetus, they grow the placenta to do that. So over all the entire process would have to change to something probably impossible. Consider the ostrich lays the largest egg now, and ostriches are larger than humans. Humans that would need a far larger egg.
The math just doesn’t work for humans to have a hard shell egg.
You are right in your final statement about the hard shell, and the size ratio, but that doesn’t make it completely impossible. Egg laying could work for humans if the shell was leathery and flexible, like that of some reptiles.
Humans could lay an egg large enough to hold a newborn, and since at the time of laying the insides of the egg would be mostly still liquid, a flexible shell would work out just fine for passage. Then the baby would develop inside the egg. Just like with birds.
The egg could also harden gradually when exposed to air, as the vagina is acidic. Especially if fertilization occurs outside the body, like with amphibians and fish. Of course, there would need to be a liquid medium, but that could also be released with the egg.
Human eggs are about the largest single cell humans produce, about 0.1mm in diameter.
But human eggs don’t provide nutrients to the fetus, they grow the placenta to do that. So over all the entire process would have to change to something probably impossible. Consider the ostrich lays the largest egg now, and ostriches are larger than humans. Humans that would need a far larger egg.
The math just doesn’t work for humans to have a hard shell egg.
You are right in your final statement about the hard shell, and the size ratio, but that doesn’t make it completely impossible. Egg laying could work for humans if the shell was leathery and flexible, like that of some reptiles.
Humans could lay an egg large enough to hold a newborn, and since at the time of laying the insides of the egg would be mostly still liquid, a flexible shell would work out just fine for passage. Then the baby would develop inside the egg. Just like with birds.
The egg could also harden gradually when exposed to air, as the vagina is acidic. Especially if fertilization occurs outside the body, like with amphibians and fish. Of course, there would need to be a liquid medium, but that could also be released with the egg.
Sure but what would be the advantage in human s case?
It’d be easier to pass a larger egg if it’s soft, even if it’s accompanied by a bunch of fluid.