How Does Natural Selection Affect Population Growth?

Charles Darwin was born in the city of Shrewsbury, England and was raised by a wealthy family and was the 5th child. His mother Susannah died when he was only eight and his father was a physician, poet, philosopher and naturalist. In 1825, Darwin graduated from the elite school at Shrewsbury. He then attended college at the University of Edinburgh to study medicine. In 1927 he dropped out and decided to study clergyman and entered the University of Cambridge. There he was introduced to Adam Sedgwick and John Stevens Henslowe. These two gentlemen showed Darwin how to observe natural phenomenon and collect specimens. Which when the opportunity arose, for him to be a member of the team, Darwin took the opportunity to travel on the survey ship,

In Darwin’s Theory, he observed in the world around him, that organisms yield more offspring than is necessary to replace themselves. So populations should increase. For example, flies can lay up to 500 eggs in batches over a three to four day period. Through observation Darwin saw for himself, that numbers in population tend to stay at about the same levels. He confirmed this observation with others. So, why don’t the numbers go up? Resources, the major influence on populations would be things such as food, water, space. As stated by (Stephen Montgomery, 2009), “A simple conclusion, individuals compete with each other for scarce resources.” Another observation Darwin made was that individuals are unique and vary in almost every aspect but the differences are passed on from parent to offspring. So the idea behind his theory is that when an organism reproduces those that survive may have heritable traits that increase their chances of survival. They will pass those traits on and the frequency of those traits will increase. When an environment changes or when individuals move to a new environment, natural selection may result in adaptation to the new conditions, sometimes this results in a new species. Natural selection can only work on heritable traits. Acquired traits are not heritable and are not subject to natural

According to the, (Encyclopedia Britannica, 2014) Phylogeny, the history of the evolution of a species or group, especially in reference to lines of descent and relationships among broad groups of organisms. The phrase “descent with modification” summarizes Darwin’s view of how evolution works. All organisms descended from a common ancestor and similar species have diverged more recently. He also shared the similarities can be found at the molecular level. The genetic code is would be universal. Example, its like that all organisms descended from a common ancestor or different organisms share genes that have been inherited from a common ancestor. Darwin’s evolutionary tree of life can explain homologies, (Encyclopedia Britannica, 2014) similarity of the structure, physiology, or development of different species of organisms based upon their descent from a common evolutionary ancestor. The genetic code is shared by all species because it goes back into the ancestral past. Homologies result in a pattern, all life shares the deepest layer and each smaller group adds homologies to those the share. Darwin’s theory proposes that small differences accumulate over time producing the larger changes we see over geologic time. Certainly, this process is always at work, but probably doesn’t not account for all