Babies are deliberately fragile - if there is an issue evolution wants to nip it in the bud early rather than wasting years of resources raising someone who is

Babies are deliberately fragile - if there is an issue evolution wants to nip it in the bud early rather than wasting years of resources raising someone who is ultimately not going to reach adulthood anyways. This is part of the reason that mortality in the first year is over 14 times higher than in the second year, even in the developed world with modern medical practices. Evolution doesn't care about babies, they are easily replaceable. Evolution doesn't care about the elderly, they have served their purpose. The most important thing is to keep people in their late teens to early thirties alive at all costs as these are the ones statistically most likely to successfully produce and raise offspring. It is no coincidence that this is also the age where people reach peak physical condition. Nature is brutal, but efficient.