Threads of Life

Thread of Life By: Roger Lewin This book covers the patterns of evolution and how each species and time era had an effect on Earths history. It covers the world from the offshoot to the present times coition us all that has happened in between. The book begins by introducing us to geology and how it is used in telling time and finding fossils. The Grand Canyon is a effective place to begin because it is the worlds greatest geological gash. Sediment was deposited here(predicate) layer upon layer and eventually the layers were cut through by the Colorado River. The time covered by the layers of rock in the Grand Canyon represent about two one thousand million years of acress history. The next chapter introduces to us how animation began. Many scientists reckon that life began as soon as the hide out cooled sufficiently after just forming. It is believed that the first life on earth emerged some four billion years ago.

The author goes on to say that the beginning of life can be unionised into five stages: first, the earth forms from materials in our solar system; second, chemicals much(prenominal) as sugars, phosphates, and amino acids are formed; third, these building blocks concern together to form nucleic acids, proteins, carbohydrates, and fats; fourth, these turn into proto-organisms; and cobblers last, these organisms gain the ability to replicate. This explains how life begins. Soon the organisms of the water begin to evolve legs and lungs and start to accident out of the water onto the land. This brings about the era of the dinosaurs. Dinosaurs ruled the earth for about 185 million years and then their populations began to decline. About 65 million years ago there is evidence that an angular struck the earth and caused the extinction of many species of marine plankton. The last of the dying dinosaur population may have died out earlier this. After the dinosaurs died off, then came the reign of the mammals. Mammals were more equipped for survival because of more intelligence and the... If you want to get a full essay, order it on our website: Orderessay

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