Seeds

Gymnosperms are the oldest organisms that still exist that evolved seeds, which are a major development in plants. A seed is essentially a plant embryo, surrounded by a food source, inside a tough covering that protects the embryo from the environment. The importance of seeds is that they allow plants to disperse their offspring and the offspring can wait until conditions are suitable for germination. Also, the offspring already have a food source available to them so development can happen even in less than optimal conditions.

The seed package also often has a method of dispersal as a means of moving the offspring farther away from the parent so they will not be competing with each other over resources. In gymnosperms, this method of dispersal usually involves the use of wind. Many gymnosperm seeds, such as those of pine trees, have a membranous ‘wing’ that acts as a sail and will be carried on the wind for short distances. When we look at flowering plants, angiosperms, we will see more sophisticated and complex modes of dispersal.