Summary:
- Plants are thought to have evolved from an aquatic green alga protist.
- Later, they evolved important adaptations for land, including vascular tissues, seeds, and flowers.
- Each of these major adaptations made plants better suited for life on dry land.
- The oldest fossils of land plants date back about 470 million years.
- The first land plants probably resembled modern plants called liverworts, like the one shown in Figure below.
- The evolution of vascular tissues revolutionized the plant kingdom.
- It allowed plants to grow large and endure periods of drought.