Why Do Chimps Attack? - Another brutal chimp attack begs the question: What makes these animals angry?

A Universitry of Texas graduate was recently 
mauled by a chimpanzee at the Jane Goodall 
Institute Chimpanzee Eden in South Africa.  

Discovery News - 

THE GIST

• Several factors could explain why chimps recently attacked a student at the Jane Goodall Institute Chimpanzee Eden in South Africa.
• Male chimpanzees, which are very strong, often fight in the wild to defend or acquire territory.
• The chimpanzees at the sanctuary were also previously abused by humans. 

Chimpanzees have made headlines in recent years for several unprovoked attacks against humans, the latest last week at the Jane Goodall Institute Chimpanzee Eden in South Africa. The severely injured victim, University of Texas graduate student Andrew Oberle, remains in intensive care.

Oberle was mauled by chimpanzees as he gave a lecture to about a dozen tourists. The brutal attack prompted many to wonder what, if anything, provoked the animals? Experts suggest that multiple reasons could explain the attack.    More