The earliest land plants are described as being small and rootless, much like liverworts. Scientists believe that these liverwort-like plants evolved from green algae as the first plants to survive on land.Continue Reading
The earliest and oldest land plants are the ancestors of the modern liverwort. These early plants, which evolved from algae that thrived in the water, had neither roots nor stems, but resembled moss. They reproduced much like moss and liverworts today, by distributing spores. In fact, scientists found fossilized cryptospores in Argentina that date back 472 million years, the oldest known plant fossils on Earth as of 2014. Before the spores found in Argentina, the oldest known spores were those scientists found in Saudi Arabia, which were 463 million years old.
Moss and liverworts are simple plants because they do not possess xylem and phloem tissue. The first complex plants with these characteristics were Rhynia and Cooksonia. Rhynia, named after the Scottish village in which the fossils were found, was a leafless, rootless plant that performed photosynthesis in its stems. It reproduced by releasing spores and by putting out rhizomes. Seed plants did not evolve for several million more years, around the very end of the Devonian period.Learn more about Botany