Life in standstill is impossible. Life was changing in the seas and developed on the shallow waters. But the conditions of dry land are much more changeable. Water environment is rather monotonous. Mountains and lowlands, swamps and deserts change their places with a dizzy (by evolutionary measures) speed on the dry land. It is impossible for a land life form to accommodate to some specific conditions hoping that flexibility will allow accommodating to new ones. These life forms had to have the huge accommodation reserve.
Slowly, gropingly the first bacterias, funguses, algae of prevendian age were getting ashore preparing the way for the main land conquerors the higher plants. Hundred million years passed. And by the beginning of Silurian the first plants got partially ashore. Only by the end of Silurian or even by the beginning of Devonian can our first finds of land arthropods be dated. This can suggest us that there already was a wide range of coastal plants present on the shores of Devonian seas and swamps. And then Carboniferous presented the richest, the most variable collections of insects, masses of plants, not only primitive ones but also the first of conifers! The multiformity of quadrupeds, though most of them still of an aquatic forms, but the totally land species were also present. This is the secret of nature.
The Essay on Adaptations Plants Had To Make To Be Able To Survive On Land
Many years ago, plants made the drastic move from water onto land. Although at first they had a very difficult time surviving on land, they gradually became acclimated to their new terrestrial habitat. This was only after they had formed adaptations to overcome a slew of problems that plagued them on land. For example, they had needed an aquatic environment for both reproduction and to support the ...
What happened in the middle of Paleozoic, why did such a dash to the dry land happened? Why did it take so much time for the Precambrian forms of bacteria to acclimatize on the shores of ancient swamps, in what way did they differ from the modern ones that can occupy any place with such a great speed? Let us remember what we know about the first land plants. In 1859 the Canadian geologists found some fossils of the primitive low Devonian leafless plants psilophytes (Psilophyton).
Later in Scotland a well preserved fossils of early Devonian rhynia (Rhynia) were found. They had much in common with the psilophytes; generally they were the same naked twigs that formed peatbogs 415 million years ago. Then the cooksonia was found; it was the early Silurian land plant. In their appearance as well as in their texture cooksonia did not differ much from the Devonian plants. Little had changed in the evolution of land plants in 50 million years. But in the late Devonian there were the richest complexes of land plants present.
And in another 50 million years the layers were filled with the good imprints of ferns, mosses and first spermatic plants. Maybe something had significantly changed, the gas mixture of the atmosphere for example? Of course something had changed, but not so rapidly! Or maybe the main thing is the change of the conditions of fossil preservation? We know quite well what was happening in the water and near the water, but concerning the inland we have only circumstantial ideas. What did the pristine dry land look like? The poor greenish gray twigs of miserable plants on the banks of lakes and rivers with the naked rocks around? Or?.. There are some reasons to doubt the veracity of the classical pictures. Maybe, on the contrary, the first semi land plants are the first semi aquatic of the land plants. Maybe the first aquatic quadrupeds are in reality the first attempt to accommodate to the water conditions and to compete with fishes.
But the facts are not enough to definitely prove any idea. We have to operate just with those ones we know for sure. The bases of basics of our life are the green plants. On the land as well as in the water these unbelievably complex chlorophyll factories produce oxygen and provide food for animals. The water was inhabited with the lower plants. The way from the lower organisms to the higher ones was long and hard.
The Term Paper on Phytoremediation Plant Plants Water
Introduction: In recent years it has become clear that some environmental chemicals can cause risks to the developing embryo and fetus. Evaluating the developmental toxicity of environmental chemicals is now a prominent public health concern. The suspected association between TCE and congenital cardiac malformations warrants special attention because TCE is a common drinking water contaminant that ...
But all in all the plants were able to get ashore and accommodate all the livable places of the Earth. This accommodation to the conditions of dry land laid the basics for the appearance of the land forms of animals. So the evolution of land animals had to be preceded by the evolution of land plants. So the development of the life cycle forms of plants that were not water dependent helped to spread the life from only water to other places of Earth..
