Lionesses have no manes. How do they know when they've grown up?

Answer 1

Girls have no beards. How do they know when they're grown up? In humans, the onset of periods signals sexual maturity (or at least a semblance thereof.) But there are psychological as well as hormonal and other physical signals as well.

Lower animals experience estrus; in other words, they go into heat and become sexually receptive.

Answer 2

Presumably, like domestic cats, when they go on heat. They are then sexually active and therefore adult.

Answer 3

Raggedy Anne, Like people they begin to bag and sag !