A young boy got into the gorilla enclosure and was confronted by a silverback male gorilla named Harambe.
The story is particularly sad because Harambe was a western lowland gorilla (Gorilla gorilla gorilla), a subspecies of western gorilla that is critically endangered.
Gorillas were once depicted as violent brutes who would kill a human at any chance encounter.
It is not a coincidence that the monstrous giant ape King Kong was portrayed as a gorilla.
However, from the 1970s onwards the primatologist Dian Fossey transformed gorillas' reputation with her pioneering studies of wild mountain gorillas.
All told, there have been three instances where children have fallen into gorilla enclosures, and in two cases nobody died.
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