Dung beetles come in two varieties, the hard working types and lazy bums. Hard working beetles locate their target by a strong sense of smell. Once located, they pull off chunks of the mess and roll it into balls, a job usually done by the male watched by his partner. Ball is then rolled straight off to a desirable location by the amorous couple who then use it as food cum breeding chamber.
Once in a while a lazy bum lies in ambush, especially while the female is not around. The male intent on rolling the ball in a straight line despite any obstacles. The bum tries to take advantage of this obsession and some times succeeds but often has to be content with a small chunk of the ball.