Ambam, a silverback western lowland gorilla at The Aspinall Foundation's Port Lympne Wild Animal Park in Kent, southeast England, walks upright -- like a person.
"All gorillas can do it to some extent," gorilla keeper Phil Ridges said in a news release. "But we haven't got any who do it like Ambam, and he is quite a celebrity at the park."
Thanks to a viral video, Ambam's silverback strut has made him into quite a celebrity around the world as well. A short clip of his stride has gotten more than 300,000 hits.
But the foundation says there's no monkey business here, because Ambam isn't the only one with an upright stride.
In fact, it's a family affair.
"Ambam's father Bitam used to display the same behavior if he had handfuls of food to carry," Ridges said. "Ambam also has a full sister, Tamba, and a half sister ... who also sometimes stand and walk in the same way."
The 21-year-old bachelor is the largest gorilla at Port Lympne at 485 pounds. Add the upright stance, and Ambam is even more imposing.
"We think he might use it to get a height advantage to look over the wall when keepers come to feed him," Ridges said. "Ambam can also carry a lot more food if he stands and uses both hands, and walking on two feet also means he doesn't get his hands wet when it is raining."
The western lowland gorilla, known scientifically as the Gorilla gorilla gorilla, has gone from vulnerable to endangered to critically endangered in less than 20 years. And over three generations (in this case, 66 years), the population may have fallen by as much as 80 percent.
On a more positive note, however, scientists from the Wildlife Conservation Society recently found a hidden "gorilla paradise" in the Lake Tele region of the Republic of Congo that may more than double the known population.
The Aspinall Foundation rescues gorillas orphaned by hunters, raises them and reintroduces them into the wild. The organization also has its own breeding population at its facilities, where it raises animals to be sent to reserves in Africa.
So far, Aspinall has returned 51 gorillas to protected areas -- including 43 that were rescued orphans. Reintroduced gorillas have had 14 successful births in the wild, helping to expand the critically endangered population.
And who knows -- maybe the reintroduced gorillas will show off some of Ambam's unique moves in the wild.