Zoophily is when a plant relies on animals to transfer pollen.
The plant uses its flower to advertise the presence of resources, including nectar and pollen, and to attract an animal pollinator. When the pollinator visits the flower to collect resources, it deliberately or accidentally picks up pollen on its body. As it goes on to forage at other flowers, an effective pollinator will deliver some of that pollen to a receptive female flower of the same plant species.
For animal pollination to be successful, several things must occur. The pollinator must touch the female stigma with the same part of its body which contacted the male anther of the first flower. It must deliver enough pollen to fertilize the ovules in the flower. It must visit the same plant species regularly enough to deliver the pollen before it is lost. If any of these tasks fail, pollination will not take place.