If all the fruits and seeds fell under the parent plant they would not survive for lack of space, air, water and sunlight.
Nature has therefore provided plants with different devices to scatter the seeds so that they do not become extinct. Dispersal of seeds is done by wind, animals, water and by explosion.
Some seeds and fruits dispersed by wind have wings like that of the seed of the drumstick and the fruit of the hiptage. Some seeds have tufts of hair like that of cotton and the madar.
Fruits that are dispersed by water have spongy or fibrous outer coats. The fibrous coating of the coconut fruit is capable of floating long distances on the water surface without decaying. The spongy thalamus of the lotus bearing fruits also floats easily on water.
Seeds and fruits dispersed by animals are provided by hooks, barbs, spines, stiff hairs and sticky glands on their surface. With these devices they are able to stick to the hair or fur of the animal or even to the clothing of man. Thus they are carried to distant places. Some of the fruits are of the tigers nail, spear-grass and love-thorn.
Birds and bats re also very useful in dispersal. They take the fruit from its tree and fly away to another tree at some distance either to eat or feed their young.
In some cases the soft fruits are eaten by animals, bird or man and the seeds pass right through the guts unharmed. They then fall to the ground in the dropping and germinate there surrounded by the fertilizer. One such seed is that of the tomato.
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