Animal expert "Jungle" Jack Hanna is suffering from dementia, believed to be Alzheimer's disease, and can no longer introduce animals to the public as he has for nearly four decades, his family announced Wednesday.
"Doctors have diagnosed our dad, Jack Hanna, with dementia, now believed to be Alzheimer's disease," his three adult daughters — Kathaleen, Suzanne and Julie — said in a statement. "His condition has progressed much faster in the last few months than any of us could have anticipated. Sadly, Dad is no longer able to participate in public life as he used to, where people all over the world watched, learned and laughed alongside him."
The women explained that their father, best known for his appearances on comedian David Letterman's TV shows, has always believed in the importance of connecting people and wildlife. Hanna thought that was what motivated them to get involved in conservation efforts.
"He always said, 'You have to touch the heart to teach the mind,'" they said in the statement. "Even though Dad is no longer able to travel and work in the same way, we know that his infectious enthusiasm has touched many hearts and will continue to be his legacy."
They noted that their mother, Suzi, remains by Hanna's side after 53 years of marriage.
Professionally, the 74-year-old retired last year from his longtime role as spokesman for the Columbus Zoo and Aquarium in Ohio. According to the bio on his website, Hanna took over as director of that facility in 1978, after having worked at a zoo in Florida.
"When I first started at the Columbus Zoo, attendance was low and the animal habitats were outdated," he wrote. "My top priority was to increase attendance by offering educational and entertaining events."
As part of the entertainment goal, in 1985, he appeared on David Letterman's late-night show. The two "hit it off." From then on, Hanna and his animals were regular guests, appearing on Late Night With David Letterman and its successor, Late Show With David Letterman, a combined 90-plus times, with Hanna playing the comedic straight man.
Hanna appeared on many other TV shows over the years, such as Good Morning America and the Ellen DeGeneres Show. He's also had several shows of his own, including Animal Adventures, Jack Hanna's Wild Countdown and the daytime Emmy-winning Jack Hanna's Into the Wild, which last debuted a new episode in September, according to IMDb.
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