The origin of the first land plants has been established
Scientists at Australian National University have discovered the oldest land plant spores. They have been preserved in rock samples in Western Australia, Science reports.
The age of the find was estimated at 480 million years. Plant spores were mixed with freshwater algae spores. Scientists noted that the discovery allows a better understanding of the development of flora on Earth.
It is believed that the first plants appeared on land 515 million years ago, during the Cambrian period. Experts have determined this by calculating how long it takes for different species to evolve. The earliest fossils of plant stems date back to the Silurian period (430 million years ago).
The early plants lacked root systems and hardwood, so they are poorly preserved in the fossil record. But the controversy turned out to be much more persistent. They had strong walls that protected them from drought and the powerful ultraviolet radiation of the early Earth. Research has shown that spores can persist in sediments for hundreds of millions of years.
The study showed that the spores found in Australia are intermediate between the primitive Cambrian forms and the more advanced Ordovician and Silurian ones. They confirmed the theoretical assumption that the first land plants evolved from freshwater algae.
Scientists noted that many of the unidentified fossils previously identified as fungi may actually be plants. They stated the need for a new analysis of scientific data.
Previously, scientists have found traces of the first forest fires in the history of the Earth. They raged 420 million years ago.