Dung is another readily available source of scent used by many animals to mark their territory, with some species accumulating and regularly adding to large heaps of droppings which act as territorial marker posts. The rabbit, vicuna, West African civet and hippopotamus are just four examples of these.
Snakes have the most unusual means of detecting scents. They use their tongue to pick up scent particles in the air. Having flicked out its tongue the snake then returns it to a special organ in the roof of the mouth which analyses the scents collected.