Darwin’s Theory of Natural Selection and How Did It Start?

 

The earth has changed over millions of years. We evolved from apes, dinosaurs became extinct and organisms have changed. However, how do we even know that? Who came up with the idea of evolution and what is it? The word evolution refers to an orderly succession of changes. Biological evolution is the change of population of organisms over generations. This idea of evolution has been suggested, explored and debated long before the eighteenth century. Early scientists noticed that new life-forms appeared to be modifications from fossils found in the same geographical area. This implied that a natural modification process was at work. However, the one who came up with the idea and later became the foundation of modern evolutionary studies, is named Charles Darwin. He was born February 12, 1809 in Shrews bury, Shropshire, England. He was an English naturalist who proposed the scientific theory of evolution by natural selection. Natural selection, also known as “survival of the fittest,” is a process where the organisms best suited to their environment reproduce more successfully than other organisms. Thus, over generations, the proportion of organisms with favorable traits increases in a population.

However, how did Darwin come up with this theory? The French scientist Jean Baptiste de Lamarck (1744-1829) was one of the first to propose a hypothesis of species modification. Lamarck proposed that similar species descended from a common  or same ancestor. Therefore, living species were descended from similar extinct species, and this  evidence shows in the fossil record. Fifty years later, Darwin used this idea to explain how species change.

Background

Darwin is the son of wealthy British physician and attended medical school at the university of Edinburgh and later enrolled at Cambridge to study for the clergy. There at Cambridge, Darwin showed interest in natural history. In 1831, he went on a trip to explore, and map areas in South America and the South Pacific. He was appointed ship naturalist which meant he had to keep careful records and collect specimen.

During his  voyage of the Beagle, Charles read Lyell’s book Principles of  Geology which talks about the age of the earth and the principle of uniformitarianism. This principle states that the Earth’s structure is the result of different processes and is always continuing. Lyell’s book inspired Darwin to be interested in geology, and it made him think about the possibility that the modification of environments is a very slow process. This was confirmed after he observed the volcanic activity in the Andes Mountains. Darwin contemplated that the arrangement of mountain extents would gradually change natural surroundings, requiring life forms that lived there to adjust to these progressions. Since these changes are longer than human life span, they would be difficult to detect. At the point when Darwin came back to England, in October 1836, his collections and the data analysis from the voyage were applauded by the scientific community.

One of Darwin’s most famous collections were the Galapagos finches. On the island, he observed species of organisms on different islands that were quite similar but had distinctive differences. He had gathered 13 distinct types of finches. For example, the small ground finches had a unique beak shape that was  different than a large ground finch on a different island. Later Darwin understood that, different types of beaks help the birds get a specific type of food. This observation for the finches lead Darwin to conclude they all originated from a few  bird or even one female. He suspected they got there from birds that had descended from a few birds or even a single female that had been blown off course from South America, 1,000 km to the east. Darwin additionally accepted that the offspring of the original finches had been adjusting to various situations and food sources for a  short time. By able to explain how and why evolution could take place, he called this mechanism natural selection.

 

A video for more clarifications:

 

For more information, you can go to these websites:

https://www.britannica.com/biography/Charles-Darwin

http://evolution.berkeley.edu/evolibrary/article/evo_25

http://darwin-online.org.uk/EditorialIntroductions/Freeman_OntheOriginofSpecies.html

http://www.blupete.com/Literature/Biographies/Science/Darwin.htm

 

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