Without favourable conditions, the seed does not germinate. Again without the favourable environment, no seedling can grow big. If all the fruits or seeds of a plant fall directly under the mother tree, then many of them will fail to germinate, for want of space, water, light and air, many of the germinated ones may die because of the shade of the plants. The rest survivors will gradually perish. So for maintaining the existence and increasing of generation of plants in favourable environment dispersal of fruits and seeds is essential.
Some fruits are carried from one place to another by human beings for their own interest e.g. Litchi, Mango, Jackfruit etc. In some plants fruits and seeds remains just under the tree. Again in some plants fruits and seeds are taken away from the mother plant by various agents and are distributed to distant areas. This process of distribution of fruits and seeds to a distant area from its mother plant by several means is called dispersal of fruits and seeds.