A pair of "cheeky" gorillas in a national park at the Democratic Republic of the Congo have been photographed posing for a selfie with park rangers who helped to rescue them as babies.
The selfie, which has gone viral on social media, shows female gorillas Ndakazi and Ndeze standing upright casually.
One is seen posing with her side profile, while the other leans slightly forward from behind a ranger, seemingly to try get into the frame.
"Those gorilla gals are always acting cheeky so this was the perfect shot of their true personalities!" said Virunga National Park in a post on Instagram on Monday (Apr 22).
The park said it was not surprising to see the animals on their two feet as most primates are comfortable walking upright for short bursts of time.
According to the park's deputy director Innocent Mburanumwe, the gorillas had learned how to imitate their carers, who have looked after them since they were found, reported BBC.
Standing on their legs is their way of "learning to be human beings", said Mr Mburanumwe to BBC.
"I was very surprised to see it ... so it's very funny. It's very curious to see how a gorilla can imitate a human and stand up," he added.
The gorilla orphanage took in Ndakazi and Ndeze when their mothers were both killed in July 2007, the BBC reported.
They were just two and four months old at the time. They were later found and taken to Senkwekwe Sanctuary in the national park.
In its Instragram post, the park noted that the photo was taken under "exceptional circumstances".
"The caretakers at Senkwekwe take great care to not put the health of the gorillas in danger," said the park.
"It is never permitted to approach a gorilla in the wild."