Answer:
I think it just all exists at once, if it never is created or destroyed. It must have just appeared at the same time at some point. It doesn't exactly come from anywhere, but that's my opinion. There might be another scientific answer out there, but that's what i think. I hope this helps.
Explanation:
The gestation period in cats stays for approximately 66 days and in every cycle a cat give birth more than 2 babies so if all cats are producing kittens at this rate, a prediction can be made that there will be lots of cats in our ecosystem. There will be cats everywhere if the number is not controlled.
As mentioned earlier, cats can starts reproducing at a young age of 6 months and right after delivery can get pregnant.