Scientists say they can now explain what happened to Knut, the famous polar bear that drowned at Berlin Zoo in 2011.
A new investigation has shown that he had a type of autoimmune inflammation of the brain that is also recognised in humans.
Knut polar bear death riddle solved - BBC News
A new investigation has shown that he had a type of autoimmune inflammation of the brain that is also recognised in humans.
Knut polar bear death riddle solved - BBC News