Throughout my years in high school and middle school, I have learned about Darwin's theories of evolution. Darwin proposed a new concept of evolution, where man like all other organisms evolved from a single predecessor over time. Darwin came up with several of his theories when aboard a year round expedition on the HMS Beagle.
On Darwin's expedition, he traveled the world and found many different fossils. His major discoveries were on the Galapagos Islands, and in South America. On the Galapagos Islands, Darwin observed a tremendous variety of finches. He noticed variation between finches on every island, where conditions varied. In South America, Darwin found a number of fossils of extinct plants and animals, similar to those found in the modern time. Throughout the expedition, Darwin collected and observed a number of fossils around the world. In the end, Darwin had collected many fossils, and had developed several of his laws of evolution. .
Firstly, Darwin concluded that evolution occurred by means of natural selection. Darwin proposed that there exists random variation among members of a species, sometimes favorable and other times unfavorable. When unfavorable, the organism does not survive and procreate. But when favorable, the organism has an advantage over the other organisms, and when it procreates, its offspring too will posses and then spread this advantage. Eventually, the minority of advantaged individuals will become a majority of the population, replacing the disadvantaged majority, and creating a more advanced and "evolved" species. This process can take millions of years to complete, and is known as natural Selection or "survival of the fittest.".
Darwin also proposed that natural selection produced "specialization", or the diversifying of species. Species specialize to form subspecies, which are better suited to live in a certain environment, allowing there to be a great amount of variation within a population.