Introduction:
Scientists believe that the gymnosperms developed from an extinct phylum whose members reproduced through spores (E. Taylor, T. Taylor, & Krings, 2009). The first true gymnosperms, however, produced seeds instead of spores. As a result, the evolution of the seeds became a fundamental adaptation of the gymnosperms to the dry conditions on land. The second factor that made the group successful on land was the development of pollen grains, which transported and protected the male gametes. Hence, unlike the seedless vascular plants, the gymnosperms became less dependent on the aquatic conditions for the success of fertilization. Instead, they gained the ability to ...