Evolutionary history of plants foliage consisted of fern-like fronds, although they were not closely related to ferns. The oldest fossil evidence of seed plants is of Late Devonian age, and they appear to have evolved out of an earlier group known as the progymnosperms. These early seed plants ranged from trees to small, rambling shrubs; like most early progymnosperms, they were woody plants with fern-like foliage. They all bore ovules, but no cones, fruit or similar. While it is difficult to track the early evolution of seeds, the lineage of the seed ferns may be traced from the simple trimerophytes through homosporous Aneurophytes. This
The Different Forms of Flowers on Plants of the Same Species is thus a triple chance of the maximum of fertility...There is thus the clearest proof that these complex arrangements have the important end of securing both a more abundant and more vigorous offspring.” Observations and experiments still continue today to further the understanding of this phenomenon instigated by Darwin in this original and seminal work. The Different Forms of Flowers on Plants of the Same Species The Different Forms of Flowers on Plants of the Same Species is a book by Charles Darwin first published in 1877. It is the fifth of his six books devoted solely to the study