Darwins Theory of Evolution by Natural Selection (Essay Sample)

DARWIN'S THEORY OF EVOLUTION BY NATURAL SELECTION
Name: Crystal Smith
Course: Biology
Instructor:
Date: 28th November 2014
Question
Darwin was not the first to consider evolution as a process but he did come up with the first effective explanation for how it happens. Describe Darwin’s theory of evolution by natural selection. Explain how this theory was a major advance over prior ideas as to how organisms changed over time. Give evidence in support of evolution and describe the driving forces for evolutionary change.
Solution
Darwin's Theory of Evolution by Natural SelectionDarwin's Theory of Evolution is a relatively young type,. Charles Darwin brought something new to the old Theories called "natural selection." Natural selection acts to accumulate minor advantageous and preserve genetic changes. It believes that some species developed a functional advantage over others and its offspring would inherit that advantage and pass it on to their offspring. The disadvantaged members of the same family would die slowly, leaving only the advantaged members of the Family. This theory is the preservation of a functional advantage that enables a species to compete better in the wild. This theory of Evolution is a slow and gradual process. From Darwin books in 1859 he said; Natural selection acts only by taking advantage of slight successive variations (Darwin 1859).The following is the summary of Darwin's Theory of Evolution by Natural Selection;
1 Phenotypic variation among individuals exists and the variation is inherited. This means that there is genetic variation; hence there is variation in every population.
2 More individual’s species are produced in each generation that withstands the conditions prevailing.
3 When there is isolation in reproductive new species will form and suitable traits will be passed on to the young ones
4 Those species with heritable traits will better suit the environment and will survive. This means that species with suitable characteristics will survive and reproduce
Darwin's theory of evolution by natural selection is the best supported theories in the history. There are much evidence from various scientific disciplines, which including paleontology, genetics, geology and developmental biology. Natural selection is well supported by the changes in various species
The following are reasons why Darwin’s theory was a major advance over other theories of evolution;
There have been many theories explaining evolution. Two of the most well known of these are the Lamarckian theory, which was mostly believed before the Darwinian Theory, which is believed to have the highest probability of it being the case. In Lamarck's theory of evolution, it states that an organism was able to pass on required traits to their offspring. This has been shown in the evolution of giraffe's evolution to having longer neck and longer legs. As per Lamarck's theory, during a bad season when all the vegetation in lower areas and can be reached by the giraffe with the shorter neck and legs had gone, they necks where stretch, to reach for food on a higher level. They have longer necks and passed this trait of longer neck and legs to their offspring. This led to the longer necks of giraffe like the one seen today with its long neck and legs.
Darwin's theory relied history that, at the start there was very many giraffes with different heights, due to the variations in species through the reproduction. Darwin stated the giraffes tried to compete and struggle to exist. During a dry season the nutrition available are low levels ,during these times the giraffes with longer necks and legs are likely to survive hence the giraffes with the shorter necks and legs would die, Cutting them from pass on their genes, resulting in a new generation of giraffes with longer necks and legs.
Also Lamarck Theory would have believed that the changes in the horse traits were due to its environment. The horse struggled to run faster and escape predators when out in the bush; hence they developed a stronger, body to with stand the need for high speed.
Darwin's theory thinks from the perspective of changes in the genes and would differ with Lamarck Theory by, saying that the horses that survived were the ones, who could run faster. And are the horses with the longer legs, and so the genes of horses with longer lags would have been passed to the off springs.
The following is the Comparison of Darwin’s theory and other evolution theories;
It was Darwin's genius both to show how all this evidence favored the evolution of species from a common ancestor and to the generation we have at the moment. Lamarck and others theorist had promoted evolutionary theories, but they used speculation in order to explain changes in life. They claimed that the evolution of different species was guided by long-term trend. For example, Lamarck thought that life rise from simple single-celled to form complex ones. Many German biologists conceived of life evolving according to predetermined rules, in the same way an embryo develops in the womb. During the mid-1800s, Darwin and Alfred Russell Wallace independently conceived of a natural, even observable, way for life to change: a process Darwin called natural selection.

The following are evidence in support of evolution and the driving forces for evolutionary change.
1 Homology:from the research animals have similar bone structures, with e superficial appearance .this is an evidence sh...