Musiara, Masai Mara (Kenya)
When 2 bull elephants of equal size meet, they literally 'size each other up' by coming together with their heads until the bases of their trunks and tusks are engaged.
Trying to be taller than the other, they press down on each other. The winner is the one that shows the most stamina, managing to hold his head higher than the other.
In this case neither of the 2 bulls showed real aggression, resulting in a 'friendly sparring match'.