"Lust" among animals.

These penguins live in Antarctica. These penguins became the heroes of several cartoons. About the most famous penguin "Lolo".

But they have one feature that the cartoon says nothing.
It's sex.

photo

As you know penguins build nests of stones. To find a good rocks pretty hard, competition is fierce.
The solution was found. Of course females.
They stroll among penguins and look out for males who's got the stones better. Approach him and begin an erotic dance.
Of course, the male becomes agitated and jumps on the female. She tries to strike a pose with my head towards the nest of the male and when it is in erotic ecstasy, just stealing the stone better. After the act goes with a stone in his mouth.
According to observation by researchers, there are females who even manage to do without sex.
Just lead males in excitement while he is in the euphoria of an upcoming pleasure, grab the stone and run away.

But the British scientist George Murray levick took an even more startling moment.

Observed that such cases occur repeatedly.
Scientists can not give a precise definition of this animal behavior. Maybe it's just the act of violence.

Maybe again some kind of self-interest?)))