Amid news that our ancestors left Africa much earlier than we previously thought, another African primate's human behaviour is making waves online.Meet Ambam, a 21-year-old Silverback Western Lowland gorilla at Port Lympne Wild Animal Park in the English city of Kent, who has become an overnight viral video star.The cause of his new-found celebrity? An upright walking style that's all too human. Check out the video below to see for yourself.Ambam has been walking like this for as long as his trainers can remember, according to the Toronto Star . He's following in his father's footsteps, who also walked upright. Ambam's two sisters have the gift too, though neither are as skilled at it.The fact that Ambam is the largest gorilla at the park, weighing in at 218 kg (480 pounds), makes his upright stance all the more remarkable. He doesn't always walk this way, however, only when he's curious - usually about food.If you're picturing the other gorillas in the pen learning from Ambam and evolving into some sort of dangerous ape species straight out of 2001 , think again. According to the Star, the other gorillas "could care less" about Ambam's exploits.According to trainer Phil Ridges, all gorillas are able to stand upright, but tend to do so very rarely. Ambam likely has a "standing-up gene" that makes him more likely to walk like a human and which his offspring may inherit.You can see more of Ambam in the video below.