Among the millions mourning the death of Robin Williams on Monday was Koko, a gorilla who communicates in sign language. Williams met Koko in 2001 at The Gorilla Foundation in Northern California, where the great ape managed to upstage the great comedic actor.
“Years later (on Aug. 11, 2014), Koko overheard Penny (Dr. Penny Patterson, Koko’s mentor and surrogate mother) talking on the phone about Robin, who had just passed away,” The Gorilla Foundation stated on its website. “She became extremely sad.”
“When you remember Robin Williams, remember that he is not only one of the world’s most beloved entertainers, he is also one of the world’s most powerful ambassadors for great ape conservation,” the organization said.
For his part, Williams called his conversations with Koko a “mind-altering experience.”
The encounter with Koko was just one of many efforts Williams made over the years on behalf of wildlife. In 2011, the actor appeared with other celebrities in a TakePart video to call attention to the annual slaughter of dolphins at the cove in Taiji, Japan, where the few survivors are sold to zoos and water parks.
“My friend doesn’t belong in captivity,” Williams says in the video. “The others are brutally killed.”
In 1995, the comedian narrated and starred in the PBS documentary In the Wild—Dolphins With Robin Williams. He followed the work of marine biologists and swam with Atlantic spotted dolphins in the Caribbean.
As with Koko, he attempted to communicate with his newfound dolphin friends.
“What’s up, my main mammal?” he asked a spotted dolphin.
Closer to his Marin County, Calif., home, Williams once made an impromptu appearance at a fund-raiser for the local humane society, jumping onstage to riff with another comedian.
“The Marin Humane Society is very sad to hear about the passing of Robin Williams,” the group said on its Facebook page on Monday. “In 2009, we were honored when he gave a surprise performance at our Woofstock benefit concert.”