The general theory of evolution is a scientific explanation for how species change over time. It is based on the idea that all living things share a common ancestry and have evolved, or developed, from earlier forms of life.

History of the Theory

The concept of evolution has been around for centuries. However, it wasn’t until Charles Darwin published his book “On the Origin of Species” in 1859 that the theory gained widespread acceptance.

Darwin’s theory proposed that all species of organisms arise and develop through the natural selection of small, inherited variations that increase the individual’s ability to compete, survive and reproduce. This process leads to changes in populations over time and eventually results in new species.

Evidence Supporting Evolution

There is a wealth of evidence supporting the theory of evolution. One key piece of evidence is the fossil record.

Fossils are preserved remains or traces of organisms from past geological ages. By studying fossils, scientists can trace the history of life on Earth and see how different species have changed over time.

Another piece of evidence comes from comparative anatomy – the study of similarities and differences in the physical structures between different species. For example, all mammals have similar bone structures in their forelimbs, suggesting they share a common ancestor.

Natural Selection

Natural selection is a key mechanism driving evolution. This process occurs when certain traits make an organism better suited to its environment, allowing it to survive and reproduce more successfully than other individuals within its population.

Over time, these advantageous traits become more common within a population while less advantageous traits become less common or disappear altogether. This gradual change within populations can lead to speciation – where one population evolves into two or more distinct species.


The general theory of evolution provides an explanation for how life on Earth has changed over time and why there is such diversity among species. The theory is supported by a wealth of evidence from multiple scientific fields and continues to be refined as new information becomes available.

As with any scientific theory, the general theory of evolution is subject to ongoing debate and scrutiny. However, it remains one of the most widely accepted and well-supported explanations for the diversity of life on Earth.