What is the evolutionary history of plants?
The evolutionary history of plants begins very long ago. Algae probably existed on wet soil for more than a billion years, but plants, as in Kingdom Plantae, did not appear until 700 million years ago. This figure comes from molecular genetic analysis, indicating that land plants are divided from green algae around that time, although this picture is not confirmed by fossil evidence. The earliest evolutionary history of plants on Earth appears in the early Ordovice period, about 475 million years ago, although many Paleobotanists suspect that there were plants that were 500 million years ago today. These plants, lacking circulatory tissues, were relatively short, between 1 and 100 mm (4 inches) in thickness. These meophytes represented the basal group in the evolutionary history of plants. They could only survive in very humid areas, who can easily take water directly directly directly and their spores could be easily dispersed. Missing a protective coating, spores are relatively toRear and susceptible to despair (drying). Scientists believe that the first land plants could prepare the soil for colonization of the soil animal sequestrations of carbon dioxide from the atmosphere in the lignin biopolymer. This has increased part of the atmosphere containing oxygen, so it is more available for oxygen breathing animals, such as the first earthly arthropods and molluscs.
About 425 million years ago, the first vascular plants appeared, as well as simple bifurizing, sporangia (spore producing structure) tilted Cooksonia and unusually advanced Baragwanathia found in Australia. Plants slowly grew in height, from just a few centimeters to approximately 20 centimeters (8 inches). At this point, the plant spreads mainly through vegetative growth, as the spores could not be dispersed too far from the parent plant. Scientists who study the evolutionary history of plants are hard to work andHe tries to find out which ground plant was actually the first and what her ecosystem looked like.
Throughout the Devonian (416 - 360 million years ago) plants gradually grew to height to become the same size as today's massive ferns. At the beginning of the Devonian, plants were mostly non -vascular and in a corresponding way small, but until the end of the period the plants carrying seeds developed and formed huge forests. The explosion of botanical diversity in this period is called the "Devonian explosion". Meanwhile, the fish ruled the sea.
Other main innovations in the evolutionary history of plants were much later, during the chalk, when flowering plants (angiosperms) first appeared. The use of flowers to attract bees, which would then continue to pollinate other plants, were angiosperms of genetically a variety and great evolutionary success. One of the latest varieties of plants is grass that developed from angiosperms 35 million years ago.