Evolution Paper

                                                               
                                                     The Idea Of Evolution


         Evolution is the theory that states that species have descended from many ancient forms of life by living matter and structural modifications.“Organic life beneath the shoreless waves Was born and nurs'd in ocean's pearly caves; First forms minute, unseen by spheric glass, Move on the mud, or pierce the watery mass; These, as successive generations bloom, New powers acquire and larger limbs assume; Whence countless groups of vegetation spring, And breathing realms of fin and feet and wing”-Erasmus Darwin. There are many philosophers that contribute to evolution. One of the major philosophers was Charles Darwin’s grandfather Erasmus Darwin. He was a man of many incredible interests and pursuits of whom he was a physician, poet, philosopher, naturalist, and botanist, and was one of the greatest leaders of the eighteenth century in England. One of his first theories on evolution was in Zoonomia, or also known as The Laws of Organic Life. Erasmus did not come up with the idea of natural selection, but he presented his focus on how life evolved from one common ancestor forming “one living filament”. He believed that sexual selection and competition can cause changes in species. "The final course of this contest among males seems to be, that the strongest and most active animal should propogate the species which should thus be improved.” Erasmus reached his final conclusions by doing observations of the behaviour of wildlife, of domesticated animals, and by presenting his knowledge in many different fields. He wasn’t quite sure how species could evolve into another, so he really debated this question. Lamark’s scientific theories was quite ignored during his lifetime, he never received the acceptance of his colleagues Buffon and Cuvier. He believed something more complex than the other philosophers, he believed that organisms are not changed by their environment. His belief was that there is a change in the environment that changes the necessities of organisms living in that certain environment, which results in a change in their behavior. His theory of evolution is different from the modern evolutionary theory. Lamarck pictured evolution as a process of increasing density and perfection. He did not believe in extinction, however he did think that species disappeared because they developed into other species. This evolutionist published a series of books about paleontology and invertebrate zoology. Out of all the books that he published Philosophie zoologique, which was published in 1809 best explains his theories of evolution. Lamarck presented his ideas in two laws and the first law was in his book Philosophie Zoologique. The result of these two laws is that there is a change in all organisms as they adapt to their environments. Charles Darwin’s theory of evolution was presented in different characteristics such as size, tooth length, or the sense of smell of individual members of a species. Like, if you smell predators far away, you will have a greater chance of survival then others that don’t have a good sense of smell. He didn’t form his theory of evolution on the idea of evolution itself, but when he went to the Galapagos Islands in 1836 he had already made many observations and had a lot of questions. Darwin believed that the earth changes over time. He said that "The town of Concepcion is now nothing more than piles and lines of bricks, tiles and timbers-- it is absolutely true there is not one house left habitable.” Ideas that he knew was that he knew that plants and animals are different by location, organisms change over time; such as how fossils relating to armadillos and sloths were found in places that similar animals were still living, and how island animals are similar to mainland animals; like how the Falklands fox was found on the South Atlantic Islands that was like a fox on mainland. While sailing through the Pacific Ocean; he noticed different forms of mockingbirds, and of the Galapagos giant tortoises he had watched might have provided clues to evolution. So, Charles Darwin had a great reputation on evolutionist.

       Microevolution is evolution, but just on a smaller term within a single population. Which basically means narrowing our focus down to one simple aspect of life. It states that changes within a population of a single species occur over time. For example, if you selected the branch of beetles then you would notice another phylogeny relating all of the insect lineages. Macroevolution is evolution on a bigger term. It states that all life is descended from one common ancestor. Some microevolutionary mechanisms include natural selection in which it is a type of mechanism of evolution, and it is one of the most basic ones. In order to understand how natural selection works you can imagine a population of beetles. First of all there is variation in the traits, like how beetles are different colors because some of them are brown and others are green. Then there is different reproduction such as how not all individuals get to reproduce to their full capability. Like for example, if the green beetles got eaten by birds then they would reproduce less than the brown beetles. Then, this results in heredity and the surviving brown beetles have brown baby beetles because this trait has a genetic basis. The end result is that whichever trait has more advantage then it becomes more common in a population. Like, in this example if this process continues on then the population of beetles will be brown. So, in order to have evolution by natural selection then variation, different reproduction, and heredity will need to be present. Genetic Drift is also a basic mechanism in which in each generation some individuals may leave behind more genes and descendents than the other individuals. The genes of the next generation will not necessarily be the healthier ones. It affects the general outlook of a population , and it doesn’t produce adaptations because it is a different process than natural selection. Genetic Drift affects all populations in which there is no chance on avoiding it. Mutation can cause parents of genes for a certain color have offspring with a gene for a different color. Like, if a parent beetle with genes for green coloration has offspring with a gene for brown coloration then it would result in making the brown genes more common in the population. Migration is when individuals from a population join up with another population. Like, if a population of brown beetles join a population of green beetles then it would make it more common for there to be brown beetle genes in the green beetle population.

        A type of evidence of evolution is the fossil record. Scientists have had the capability of putting together a time scale for the history of life on earth by dating fossils. Fossil evidence states that over time organisms of increasing involvement appeared on earth. Blue and green bacteria are the first fossils that were maintained from the Precambrian era. Complex invertebrates controlled life in the oceans during the Paleozoic era. Plants and animals had inhabited the land surface of the earth at the end of the Paleozoic era. There are many examples on the fossil record that interpret that species have evolved from many ancient organisms, according to scientists. Embryology is the study of the formation, development, and growth of embryos. Embryos start off by looking alike in the early stages of development, and the evidence shows that organisms had a common ancestor. Biochemistry shows that there is a biochemical similarity in all living things. DNA is one of the mechanisms for gene activity and inheritance in all living organisms. So, the evidence shows that the structure of the genetic code is almost exactly the same in all living things. Comparative morphology is the analysis of the patterns of the locus of structures within the body plan of an organism, which shows similar patterns of the body plan of organisms. The only type of evidence that shows me that species have changed over time is the fossil record because it the most accurate out of the other types of evidence. There is a lot of examples on the fossil record that shows that species have changed over time. The time scale represents the history of life from long ago, and how species have changed. In conclusion, evolution is just another theory out there, and some of it is correct like how it proves adaptation but most of the facts that it proves to be true, are not true in my opinion.


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