Charles Darwin: Theory of Evolution and Natural Selection
Charles Robert Darwin is also known as Charles Darwin who was born on 12 February, 1809 at Shrewbury, Shropshire, England. His scientific theory of evolution by natural selection became the foundation of modern evolutionary studies. Let us study in detail about the theory of evolution by natural selection through this article.
Let us tell you that the theory of evolution by natural selection was first formulated in Darwin's book "On the Origin of Species" in 1859. It is explained that organism change over time as a result of changes in heritable physical or behavioural traits. These changes will allow an organism to adopt better in the environment and help to survive and to have better offspring.
What is evolution?
Evolution means that species of organisms and population change with time. As we know that Darwin wrote a book Origin of Species. In it, he told that species evolved and all living things can trace their descent to a common ancestor. He also suggested a mechanism for evolution and that is natural selection. In this method heritable traits that help organisms to survive and reproduce become more common in a population over the time.
Theory of Evolution by Natural Selection
Darwin’s theory points out that life of living organism is related and has descendents from a common ancestor whether birds and bananas, fishes, and flowers all are related. Also, Darwin's theory says that complex creatures evolve from more simplistic ancestors naturally over the time. Therefore, we can say that genetic mutations randomly occur with an organism’s genetic code and the mutation that is benefited is preserved because they aid survival and this process is known as natural selection. Also, these beneficial mutations are passed on to the next generation. With the time the mutation that is benefited accumulates and a different organism is formed with entirely different creature. According to Charles Darwin natural selection acts to preserve and accumulate minor advantageous genetic mutations.
Key observations of the theory
- Traits are often heritable: As we know that in the living organisms, several characteristics are inherited or are passed from parent to offspring.
- More offspring produced but hardly survive: More off springs are produced as organisms are capable of producing more offspring than their environment can support. Therefore, there is a competition for the limited resources in each generation.
- In their heritable traits offspring varies: In their traits, offspring slightly varies from one generation to another whether in colour, size, shapes etc. and various features of these are heritable.
Observations of Darwin’s
He concluded that in a population, some individuals will have inherited traits that will help them to survive and reproduce. With the helpful traits the individuals will leave more offspring in the next generation than their peers and also the traits makes them more effective at surviving and reproducing.
- As the traits that are helpful are heritable and organisms with these traits leave more offspring, the traits will tend to become more common in the next generation.
- Over the generation the population will become adapted to its environment.
Darwin’s explain all the possible patterns that he has seen during his research.
So, we understood that natural selection depends upon the conditions of the environment, natural selection acts on the existing heritable variation and from random mutation heritable variation comes. Also, we can't ignore the fact that evolution by natural selection and their mechanisms underlies the incredible diversity of present-day life forms and the process of natural selection explains the relationship and changes between present day organisms and their environment.