Wahoo!

Male baboons make very loud testosterone laden calls that sound like a "Wahoo!" They do this, not necessarily as a desire for a physical fight, although the wahoos might escalate to that point, but as a means of posturing and positioning in their hierarchy. The male baboons display their lung capacities as they're rapidly swinging through branches, which shows off their strength and stamina. At the end the winner might become the alpha male and get the ladies.