Chantek the orangutan was 39 years old when he died Monday.
Chantek’s cause of death isn't known, but the zoo says veterinarians had been treating him for progressive heart disease.
Chantek was brought to Zoo Atlanta in 1997 at the age of 19. He was born at Atlanta's Yerkes Language Research Center and spent nine years living with researchers at the University of Tennessee-Chattanooga.
Researchers raised him like a human child and taught him at least 150 words in American Sign Language.
He was taught other human skills, such as using a bathroom and cleaning his room.
Zoo Atlanta says Chantek was given a "naturalistic" living environment with other orangutans once he arrived there.
“Chantek will be deeply missed by his family here at Zoo Atlanta. He had such a unique and engaging personality and special ways of relating to and communicating with those who knew him best,” Hayley Murphy, DVM, vice president of animal divisions, said. “It has been our privilege to have had him with us for 20 years and to have been given the opportunity to offer him a naturalistic environment where he could get to know and live with his orangutan family.”
A postmortem exam of the ape is scheduled to be performed.
“Chantek’s long life is a great testament to the dedication of his care team and to the work of the Great Ape Heart Project, the combined efforts of which made it possible for us to give him the best care and quality of life the zoological community has to offer,” Murphy said.
Click here for more information on Zoo Atlanta’s official website.