Wild gorillas face regular threats like poaching and habitat destruction, but their captive counterparts don't always have it better.
This primate is one of six western lowland gorillas who live at the Bristol Zoo in the U.K. He was chewing on some grass on July 6 when photographer Bob Pitchford started taking his picture. The gorilla soon offered up this gesture.
"He really does look a bit cheesed off," photographer Bob Pitchford told the Bristol Post. "When I saw the pictures, I just thought 'you little devil.'"
"I quite regularly photograph the animals at Bristol, but I've never seen anything like this," he added.
It's not clear what prompted the Bristol gorilla's gesture, but gorillas in zoos around the world have thrown up middle fingers at tourists in the past.
One gorilla at Busch Gardens in Florida flipped the bird at a fellow ape back in March. Onlookers caught the incident on video:
Gorillas live in groups and communicate among themselves with vocalizations, olfactory signals and intentional gestures like movements and facial expressions.
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