Woodland Park Zoo's beloved gorilla "Leo" died of an aortic aneurysm according to zoo officials.
That's a rupture of the major artery that exits the heart. Leo was 40 years old.
The 360-pound gorilla was the leader of the gorilla group at the zoo. Leo, or Leonel, came to Woodland Park Zoo in 2008 and became a surrogate father to a baby gorilla named Yola.
Leo had been under 24-hour care the week before he died. He had shown signs of improvement, but unfortunately died suddenly in the presence of his gorilla keepers and close.
Gorillas are social animals, say zoo officials, so Leo's body was kept overnight at the gorilla compound so his family and keepers could be with him.
The median life expectancy for a male gorilla is 32, but gorillas in zoos can live into their 40s and 50s.
