You selected the ancestor to the divisions Coniferophyta, Ginkgophyta, and Anthophyta. These are the so-called seed plants. These divisions share three major characteristics that were not found in plants that had evolved earlier and therefore indicate th at these plants came from a common ancestor.
As shown in the following figure, seeds contain, nourish, and protect the developing embryo of the plant's diploid, sporophyte stage.
As shown in the following figure, pollen is the tiny, two-celled male gametophyte (haploid) stage of the plant's life cycle. Because of its small size and light weight, the pollen can be dispersed by wind or animals from plant to plant; once it reaches a receptive female gametophyte it develops sperm. Thus, unlike the plants that had evolved previously, seed plants are not dependent upon environmental moisture to carry the sperm to the eggs.
These plants have a life cycle in which the diploid sporophyte stage is large, and the much smaller haploid gametophyte stage develops attached to, and nutritionally dependent upon, this large sporophyte stage. For more details on plant life cycles, you can review the general plant life cycle . To see how the fact that the gametophyte develops attached to and dependent upon the sporophyte contrasts with life cycles that had evolved previously, you can look at how the gametophyte stage develops in the Bryophyta and the Pterophyta .
Return to general information on the characteristics used to classify plants.