What are Earth's oldest plants?

The oldest evidence for the oldest plants of land appears as a small tetrad spores dated 470 million years ago, since the Middle Ordoviku period. They came from Mosses and lichens. At that time, the Earth would mostly be deserted, covered with deserts and Badlands, with little greenery that will be seen, except for the eyelashes on the edge of streams and ponds. Green algae took the first steps on Earth, and green algae is assumed that all plants have developed the land. This idea is supported by genetic and morphological studies.

At first, all soil plants were mesheophytes (non -accurate), which means that they lacked specialized tissues for the transport of water and nutrients found in most modern plants. These plants had to suck their nutrients directly from the environment or die. Early the ally of pioneers of algae, the ancestors of the oldest land plants, were mushrooms whose hyphs (fungal hairs) are found with these fossils. This is what is a lichen - close to the symbiotic relationship between the HouboU and green algae. Symbiosis of fungal plants continues to this day, because numerous plants have hubs living in their roots and help them draw nutrients from the soil.

The oldest land plants known with vascular tissue date back to the Silurian period, about 425 million years ago, when small organisms such as cooksonia appear in fossil record. Cooksonia was a vascular plant with simple stopwatch that shows several Y -shaped branches as they rise to sporangium, spherical package of spores that peaks. The simple structure of the plant included no leaves or visible roots, although the roots could be omitted by the fossilization process. For most, the plant looks more like a sponge than the green plants with which we are known. Regardless, it was among the oldest land plants.

approximately at the same time as the oldest land plants were olderEarth animals began to inhabit these nascent mini-lesses. These animals included arthropods similar to contemporary bristlet that, early chelicerates related to modern spiders, Millipedes, Centipedes and Small Scorpions. It would not be until the middle of the Devonian, several tens of millions of years later that the first real forests appeared on the ground.