When a dying chimp recognizes her old friend

This clip will surely make you cry...

When a dying 59-year-old chimp recognizes an old friend.

Mama, a chimpanzee at the Royal Burgers Zoo in Arnhem, Netherlands, was very ill and stopped taking food and drinks.

Professional of Behavioral Biology Jan van Hoof, 81, has known Mama since 1972 and paid a visit to say goodbye to her. Mama died one week after her old professor friend's visit.