Why seeds must travel
The scattering of the fruits and seeds formed on a plant far away from the mother plant is called dispersal of fruits and seeds.
A seed that simply drops has landed in the worst possible place — directly beneath a large plant of its own kind, in its shade, competing with its roots. Through dispersal, plants fulfil the following needs:
- minimising competition for essential factors;
- finding new habitats;
- increasing in diversity;
- being protected from pests and disease-causing organisms.
The four methods
There are four main methods by which dispersal of fruits and seeds takes place in plants:
- animals
- wind
- water
- explosive mechanism (bursting)
The same three agents, a second time
Animals, wind and water carried the pollen; now they carry the seed. The fourth is the plant's own — and the only one of the four that costs it nothing to hire.
Assignment 14.3
- Identify and name the dispersal agent by which the kinds of fruit you come across are dispersed.
- Write down two adaptations each that those fruits have for being dispersed by means of that agent.