Charles Darwin (1809-1882) From a young age Charles Darwin disliked school and instead he liked observing birds and collecting insects to study. When he was 16 years old, Darwin was sent to a medical school in Scotland, which he found as a waste of time. In 1827, Darwin enrolled in the University of Cambridge, England. He also though that his time was wasted there too, as far as academic studies were concerned. Henslow, a professor of botany in Cambridge and Darwins friend, encouraged Darwin in his studies of natural history.
In 1831 Henslow recommended that Darwin be chosen for the position of naturalist on the ship the HMS Beagle. For Darwin, the Beagle was chartered for a five-year mapping and collecting expedition to South America and the South Pacific. Darwin read a geology book given to him by Henslow, called Principles of Geology, by Charles Lyell. After collecting fossils in the Andes, observing results of earthquake in Chile, and studying thousands of different species, he came up with the conclusion that new new kinds of living organisms form every time land changes. When Darwin returned to England in October 1836, his collections from the voyage were praised by the scientific community. Observing similarities between different and fossils, Charles Darwin came up the idea that species could have common ancestors.
Comparing homologous structures, vestigial organs, and embryological development of living species gave him additional evidence of evolution. In 1838 Darwin read a book called Essay on the Principle of Population, by Thomas Malthus, which stated that the human race was in great struggle of existence, competing of the limited resources. Combining the idea of competition with his other observations, Darwin explained how evolution could occur. First, he stated that variation exists among individuals of a species. Second, he stated that scarcity of resources in a burgeoning population would lead to competition between individuals of the same species because all use the same limited sources. From these reasoning Darwin concluded that individuals having advantageous variations are more likely to survive and reproduce than those without advantages, which leads to his theory of Natural Selection.
Darwin compiled evidence by evolution by natural selection for about 20 years. Between 1842 and 1844 he wrote a 230-page essay summarizing his theory and evidence for it. A British scientist, Alfred Russel Wallace (1823-1913), came up with Darwins same idea in 1858, and wrote to Darwin. Darwins fellow scientists persuaded him to let them present his theory and Wallaces jointly as at a scientific meeting. However, the publication of Darwins book The Origin Of species in 1859 changed biology forever.