[Biology Class Notes] on Charles Darwin Theory Pdf

The English naturalist named Charles Darwin had developed a theory known as Darwinism theory in biological evolution. This theory states that through the process of natural selection of the small, inherited variations which increase the ability of the individual for competing, surviving, and reproducing, all the species of the organisms arise and develop. This theory is basically called the theory of evolution.

Charles Darwin made an extensive study in the 19th century on nature for over two decades. His observations on the animal distribution plus the relationship between the living and the extinct animals became very prominent in the coming years. Owing to his contribution to the theory of evolution, Charles Darwin came to be known as the father of evolution. 

Darwin’s Contribution

In the 19th century Charles Darwin conducted extensive study related to nature for more than 2 decades. The observations related to animal distribution, plus the relationship between the living and the extinct animals was found by him. He also found that it’s not just these but there is also a relationship between other species that used to exist millions of years back and present animals who share similarities to some extent.

The Theory of the Evolution

These are some of the ideas that were given by Darwin on the theory of natural selection.

• The species keep on changing or evolving with time. As the environment changes, the requirements of the organisms also change and they need to adapt to their new environment. According to the natural requirements, the phenomenon of change over a period of time is known as adaptation. 

• According to Darwin’s theory, only higher changes tend to get naturally selected and lower ones are automatically eliminated. This leads to the progressive evolution and not all the adaptations are able to contribute. 

• Almost all the organisms share a common ancestry with some of the organisms. All the organisms had a common ancestor at some point of time and this kept on diverging since then according to Darwin.

• As per Charles Darwin, evolution is a gradual and a slow process. The process of evolution has taken place over a long period of time. When we talk about evolution we are referring to billions of years. A period of time where the entire generation of species has been taken over by another. Since adaptation and changes take a long time to get stabilized, it is a very lengthy and steady process.

Importance of the Charles Darwin Theory

There have been various theories that have been propagated by Charles Darwin. These theories have been accepted and are followed as a possible explanation for the existence of life on earth. There is a huge significance to the theory of Darwin and the impact that it has on science. 

Some of the observations from the theories of Charles Darwin are as follows. The first forms of life in the form of cells appeared about 2000 million years ago on earth. The single-celled organisms were followed by multicellular organisms and then invertebrates were formed. The different organisms began to invade starting from water and then navigating to land, and there was an evolution of the jawless fish. After that reptiles, amphibians, and some viviparous mammals evolved into existence. 

Features of Charles Darwin Theory

The theory of evolution suggested  by Charles Darwin is the most accepted theory and the best explanation of the existence of life on the earth. Charles Darwin Theory is considered as an important theory because of the following reasons:

• It stated that the first cellular forms of life existed on the earth about 2000 million years ago. 

• Later single celled, multicellular and invertebrates were formed.

• Jawless fish also evolved and different organisms started living on land from water. Later, other animals such as viviparous mammals existed. 

• The primates that were similar to today’s gorillas and chimpanzees existed about a million years ago. 

• Living organisms reproduce and grow naturally.

• No two individuals are similar to each other and they differ in their physical features, behavior and other characteristics. 

• Some features are transferred from parents to their offspring. 

• The rate of reproduction differs in all living organisms. Some reproduce more and some less.