Ferns represent the second major step in the evolutionary sophistication of plants.
As an inidication of this extra evolution, the gametophyte stage of growth is significantly reduced. In this way, a fern can be thought of as the inverse of a moss. Modern flora usually include keys for identifying ferns as well, thus further increasing their exposure to our roaming curiosity. Male and female sex organs are located on the underside of the prothallium and, when conditions are right, the sperm swims from the male antheridium to fertilize the egg in the archegonium . The result of this union is the fern plant we have come to know and recognize.