Ants don't have complex emotions such as love, anger, or empathy, but they do approach things they find pleasant and avoid the unpleasant. They can smell with their antennae, and so follow trails, find food and recognise their own colony. ... Yet a colony of ants has a collective brain as large as many mammals'.

Do ants feel pain when you step on them?

They don't feel 'pain,' but may feel irritation and probably can sense if they are damaged. Even so, they certainly cannot suffer because they don't have emotions.

Do ants get sad when other ants die?

Turns out ants don't really mourn or grieve or even have graveyards for the same reasons we as humans do. It all comes down to chemicals and smells and pheromones.