why dont other mammals cry?

Answer 1

Most land mammals can be forced to shed tears. But few do so as frequently and without overt external cause as humans. It is assumed that although they COULD cry, they don't because the are simply not complex enough to have emotions.

There is evidence to suggest that this is not entirely the case, however. Elephants and gorillas have both been observed to cry, and just about any cat or dog owner can tell you that their pets have moods of one sort or another.

So perhaps what's really happening is a middle ground. Animals have emotions, but because they can't predict, remember, and appreciate different levels of situations with our faculty they just don't experience them quite as we do.

Link 1 is to a whole book on the subject of animal emotion. Hope that helps!

Answer 2

They do.young mammals will cry for their mothers if they are left too long
they may not have tear ducts the way humans do though

Answer 3

All mammals can feel sad. Sea animals have tear ducts.