The International Species Information System, which maintains records on animals at 700 institutions around the world, said Jenny is the oldest gorilla in its database.

"I think it's amazing," said Kristen Lukas, curator of conservation and science at Cleveland Metroparks Zoo in Ohio and the gorilla species survival plan coordinator for the Association of Zoos and Aquariums. "I think it's a testament to the good care that she's received at the Dallas Zoo and also the resilience of gorillas in general."

Lukas said gorillas in the wild normally would live to age 30 or 35. Health care and protection from predators has extended the lifespan in zoos.

Jenny gave birth in 1965 to a female named Vicki, who was sent to Alberta, Canada, at age 5. Zoo officials aren't sure why Jenny hasn't conceived again.

Jenny's keepers describe her as very sweet though a little bossy.