Evolutionary Trends in the Plant Kingdom

There has been a development from simple to complex, from less organized to the more organized plant body. Also, a move from aquatic habitat to terrestrial habitat as a result of which the advanced plants are less dependent on water and adapted to terrestrial life.

• The Thalophytes (algae) are the most simple in the plant kingdom. They are aquatic, lack vascular tissues, no roots, stems or leaves.

• The algae are followed by the bryophytes (mosses and liverworts) which are terrestrial, having progressed from water to land, though they still depend on water for reproduction. They are found in moist places, non-vascular, lack roots, stems and leaves, but have root-like, stem-like and leaf-like structures.

• The pteridophytes are more complex than bryophytes. They are vascular and less dependent on water (terrestrial).

• The spermatophytes are the most complex and most dominant land plant. They are fully adapted to land conditions, and not dependent on water, with pollination being carried out by wind or insects. They are vascular with vascular bundles.

Summary of Kingdom Plantae: