How can animals disperse seeds?
Seeds can be dispersed when an animal consumes the seeds and later excretes it, or if the seed catches onto the fur/skin of the animal and falls off later.
One of the means seeds can be dispersed by animals is when animals eat the seeds. This usually happens with fruit bearing plants, where the sweet fruit entices the animal into eating the seeds. It does what it does and later excretes the seeds in another location, which can then grow. The most common examples are berries, such as raspberries.
Other seeds have hooks on them which can catch onto the fur or skin of animals. The animals catch them when they brush by the plant and later, the seeds fall off in a different area where they can grow.
A very cool example of symbiotic mutualism is squirrels and oak trees. The squirrels take the acorns from the trees, and eats some, but buries many. They often forget where they buried the acorns and they can grow. This is important because when the acorns fall just under the tree, they often don't have enough light to grow and many can not germinate on the surface. The squirrels have a source of food and the trees have a way to spread their seeds throughout the area.