why animals like dogs and cats can give birth to multiple offspring at a time whereas humans can only give birth to (most of the time) one child only at a time?

Question

why animals like dogs and cats can give birth to multiple offspring at a time whereas humans can only give birth to (most of the time) one child only at a time?

In: Biology

Answer 1

Basically Biology has come up with two reproductive strategies.

R selection, where organisms breed regularly, have large litters and grow quickly, a good number might die but so long a some make it to adulthood its a win

or K-selection. Where organisms breed slowly have limited numbers of offspring at any 1 time, grow slowly and the offspring’s survival is ensured by high levels of parental investment. Each individual is more likely to survive to adulthood but f they don’t it a far greater loss to the parents in terms of investment in passing on their genes

Both work, and what type given organism evolved depends on a number of outside factors, size, stability of environment, resource availability etc but the bottom line is apes K select, small carnivorans more often than not R select