Question
It is known that older kittens and adult cats are usually lactose intolerant.
Yet almost all (except just 1) of the cats I've known/had love milk and will steal milk products. And they all get smelly stools or slight diarrhoea after lapping up the milk.
Why is this? Why do they want something they cant digest?
Answer
Cats have an instinctive love of milk, because if they didn’t, they’d die as kittens.
After a few months, their mother will wean them, and there is no more milk to be had. Their ability to process it goes away, but there is no need for a second instinct to stop loving milk at that point, which could potentially activate too early and kill them.
Even if they do manage to find some milk as adults, it won’t kill them, which is all that matters to the evolutionary process. A bout of smelly/runny poop just doesn’t matter.
Answered By - StephenS