Gorillas can either walk on fours or twos depending on the circumstance but they often traverse the earth on four limbs support themselves on their knuckles (knuckle-walking). There are a few occasions when gorillas will be seen moving on twos. Firstly, if gorillas have to use their hands to old food, they are forced to resort to using two legs. Gorillas also stand on twos when they feel threatened; with an intention of appearing bigger and scaring away their enemies. Sometimes the playful juveniles get onto their two feet to exhibit, or when they are playing.