North America's oldest zoo-born orangutan has passed away at Seattle's Woodland Park Zoo.
Towan, a 48-year-old male hybrid Borneo and Sumatran orangutan, had been experiencing respiratory problems and died at the onset of a physical exam, the zoo said.
Median lifespan for orangutans is 28 years old, said the zoo, with life expectancy topping out at about 59.
The World According To Orangutans: Photos
"There were serious concerns for a significant health risk due to his age, chronic renal insufficiency and progressive respiratory symptoms," said Dr. Darin Collins, Woodland Park Zoo's director of animal health.
Upper respiratory tract disease is a common, and often fatal, problem in orangutans, whether wild or captive, the zoo said. Why the disease is so prevalent is not yet well understood.
The great ape and a twin sister named Chinta were born at the zoo in 1968, the first known twin orangutans to be born in a zoo. The two were famous in their day and even appeared in Life magazine.
Something of an artist, "Towan absolutely loved experimenting with finger paints and sidewalk chalk," said zoo collection manager Pat Owen. "He was so intense during his painting sessions; he took his artwork very seriously. We'll miss his unique artwork."
Here was Towan working on his art: