Plants evolved more than 400 million years ago and developed into two main types: vascular and nonvascular. Many more plants have evolved since the first freshwater algae adapted to dry land, but close relatives still exist today.
Vascular Versus Nonvascular
Vascular plants have specialized tissues that allow them to transfer water, minerals and nutrients throughout the plant. As a result, vascular plants can grow into very large plants, like trees. Nonvascular plants lack these tissues and cannot transfer water up a stem like a tree, which keeps nonvascular plants small.
The fossil record dates the oldest vascular plants to 439 to 409 million years ago during the Silurian period. Nonvascular plant fossils don't show up until 409 to 354 million years ago in the Devonian period. While scientists tell us that nonvascular plants were the first to evolve, they just don't show up in the fossil record. Later, vascular plants evolved from nonvascular plants.
Plants evolved from freshwater algae. Changes in water levels left algae stranded on the shoreline, and some of that algae was able to adapt and eventually evolve into land plants. Scientists have determined that some nonvascular plants share distinct traits with two types of freshwater algae.