Home for animals

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 Life itself is a great mystery - how and when it started? There is a theory that the Sun acted on the molecules that were attached, formed the chain and created similar molecules to which they were "fed." Some of those molecules contained chlorophyll, which has made life on the ground, giving the plants- a bottom of a food chain. The living world is composed of several elements: carbon, nitrogen, oxygen, hydrogen, phosphorus and sulfur, which are interconnected. From this, carbon and hydrogen always enter the composition of living beings. The product of molecular reactions was the creation of the plant world. Other elements such as calcium, iron, magnesium, copper... make up an inanimate part of nature that enables living beings to function (in fact, we are partly dependent on these elements because they allow us to function and we have to take them with food, but this is different story.) After the great volcanoes that ejected the hot lava and forming of the soil, the formation of mountains, the formation of the earth, the appearance of water, wind, deserts and ice, life on Earth could begin to evolve. Certain species served as a rock material, where calcium carbonate from their bones dissolved in time and formed forms, while some other species became fossil fuels. One of the oldest inhabitants of our planet is algae, at least the fossils found shows so, and the time before that is called the azoic- "Age without life." Next came the "oldest life" - paleozoic, "middle life" - the Mesozoic and "new life" - the cenosoic. The first more complex organisms from the world of animals were sponges, worms, brachiopods, molluscs and echinoderm. In Ordovician, the following period, began to develop vertebrates like chordates. All the animals lived in the water, which changed in the silurian period, when the real vertebrates were formed. Among the first land animals was the land scorpion, the most resistant the animal of today, which can live without food and water for up to a year. Creation of the first land plants also begins. Period Devonian was called the age of the fish, due to extreme conditions that included frequent change of the land from the water into the dried areas. The plants were advanced and some even began to produce seeds. In the era of carboniferius the sea was full of life, the first forests are being created on the shores of the lake, the first winged insects are created (the Meganeura had a span of 70 cm and is the largest insect so far appeared), the spiders and centipedes appeared. The sharks developed during the Devonian era and many species of fish disappeared, leaving the place for new. In this period reptiles appeared as well as the ancestors of amphibians. After that extreme temperature changes began, destroying so many species of marine animals. The creatures evolved and changed their forms, and the amphibians became larger. Permian period represents an end of the Paleozoic's era. The period represents the first period of Mesozoic, known as the "era of reptiles" in which from reptiles developed the most famous beings of prehistory- dinosaurs. It started with the development of our order, Mammalia, but the dinosaurs were the strongest species. Order Mammalia had a certain number of vertebras, the most developed brain, a higher body temperature and the first forms of life of that order were no bigger than today's mouse. At the time of the Jurassic flies, termites, first flowers (like today's lotus) appeared, just like the number of insects (which began to feed on flowers), the large amphibians disappeared. Birds (archaeopteryx) appeared, which were still something between reptiles and today's birds, which turned the scales into feathers. In the Jurassic period two types of winged reptiles, pterosaurs and birds, evolved. During the Cretaceous period the birds envolved, the reptiles become insignificant, the giant water reptiles disappeared. All today's insects are developing in Eocene, many invertebrates get their shape close to today, the most common are marine animals with bones and only reptiles that we have now remain, while dinosaurs have disappeared into the time of the Mesozoic. Mystery is what happened to them. Group of fish, fish with bones, developed, but the biggest shift happened in the order of Mammalia, where there was a split in marsupials and rael placental animals.Marsupials were larger group but they slowly disappeared and remained only in some parts of the Earth's hemisphere. Over a million years ago Quaternary began, in which was one of the larger ice ages (Pleistocene), the transformation of the fertile Sahara into the desert, complete switch of the living world. Differences in the relief of the continents have influenced the fact that several plant species are retained in some parts. During the Pleistocene period, a human also appears. Life that we know begun.
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