Giraffe Necking

 
Male giraffes use their necks as weapons in combat, a behavior known as "necking".

 

Necking is used to establish dominance and males that win necking bouts have greater reproductive success.[12] This behavior occurs at low or high intensity. In low intensity necking, the combatants rub and lean against each other. The male that can hold itself more erect wins the bout.[25] In high intensity necking, the combatants will spread their front legs and swing their necks at each other, attempting to land blows with their ossicones. The contestants will try to dodge each other's blows and then get ready to counter. The power of a blow depends on the weight of the skull and the arc of the swing.[25] A necking duel can last more than half an hour, depending on how well matched the combatants are.[10]:331 Although most fights do not lead to serious injury, there have been records of broken jaws, broken necks, and even deaths.[12]

After a duel, it is common for two male giraffes to caress and court each other. Such interactions between males have been found to be more frequent than heterosexual coupling.[65] In one study, up to 94 percent of observed mounting incidents took place between males. The proportion of same-sex activities varied from 30–75 percent. Only one percent of same-sex mounting incidents occurred between females.[66]

https://en.wikipedia.org/wiki/Giraffe#Neck

Giraffes rarely fight, but when they do, it's a hypnotic spectacle. 

The Discovery Channel caught a pair of giraffes locked in heated battle, and the footage they got was nothing short of spectacular.

Giraffes are "gentle vegetarians," according to the narrator, but they will fight to protect precious territory by swinging their 6-foot-long, 500-lb necks into each other.
In this case, the precious territory is a stretch of land in the Hoanib sand river in Namibia.

http://www.businessinsider.com/fighting-giraffes-gif-2013-1#ixzz3i0VwlF2k