The Mamas, a 59 year old female chimpanzee and the older Chimp colony of Royal Zoological Park Burgers in Arnhem, the Netherlands, He was seriously ill. Refused any attempt of responsible to feed.
Professor Jan van Hooff (behavioral biologist and co-founder of the colony Burgers), who knows the Mamas since 1972, He visited a week before he died of old age in April 2016.
It took some time before the Mamas perceive the presence of an old friend. The reaction was extremely moving.