< What Darwin Never Knew >

– How the Discovery of DNA Proved Darwin’s Theory –

Charles Darwin

(1809 ~ 1882)

Charles Darwin was a British naturalist known for his theories which greatly contributed to the way we perceive evolution today. His book, <On the Origin of Species>, introduced the process of evolution through natural selection.

However, even Darwin himself was unable to explain why these changes occurred, since this was before the discovery of DNA. After the discovery of DNA by James Watson and Francis Crick, Darwin’s theory was proved correct, and the reason as to why there are so many varieties of organisms was made clear.

When a certain kind of mutation occurs, the features of organisms go through changes which may even help them adapt to their surroundings and increase their chances of survival. DNA switches enable genes to turn on and off, causing significant changes to occur in organisms.

As Darwin did not have any knowledge of genetics, the fundamental reason to these mutations was unknown to him.

For example, the beaks of the Galapagos finches went through a dramatic change according to their surroundings. The finches with beaks that could surmount the environmental adversities they faced regarding feeding survived and reproduced, passing down their genes to their offspring. As a result of natural selection, the beaks of the finches would vary depending on what they feed on.

As for fruit flies, several fruit flies have spotted wings while others do not, and this depends on whether the paintbrush gene which codes for the black wing spots is turned on or not.

The same applies to the stickleback fish. The reason as to why the lake sticklebacks lost their spikes was because a mutation occurred in which the switch for turning on the gene for spikes was broken.

Modern science was able to prove Darwin’s theory to be accurate, and this will continue to serve as  crucial information for further scientific investigations to be made in the future.