Is Evolution a Theory or a Hypothesis?


Jane Flores

Evolution is one of the most widely accepted scientific theories in the world, but there is still some debate about whether it is a theory or a hypothesis. In this article, we will explore the difference between these two terms and examine the evidence that supports the theory of evolution.

What is a Theory?

In science, a theory is an explanation for how and why things work. It is a well-established and extensively tested framework that explains natural phenomena. Theories are based on empirical evidence and can be modified as new data becomes available.

What is a Hypothesis?

A hypothesis, on the other hand, is an educated guess or prediction about an observation or phenomenon. It is a proposed explanation that has not yet been proven or tested through experimentation.

The Evidence for Evolution

The theory of evolution proposes that all living organisms share common ancestry and have evolved over time through natural selection. This theory is supported by an overwhelming amount of evidence from various fields of science.

One of the strongest pieces of evidence for evolution comes from comparative anatomy. Scientists have observed that many different species share similar physical structures, such as limbs and bones, which suggest they evolved from a common ancestor.

Another piece of evidence comes from genetics. DNA analysis has shown that different species share similar genetic sequences, indicating they are related by descent.

Fossil records also provide evidence for evolution. Scientists have found fossils of extinct species that show intermediate stages between different groups of organisms, providing evidence for gradual changes over time.

The Difference Between Theory and Hypothesis in Evolution

While it may seem like the theory of evolution could be classified as a hypothesis because it has not been directly observed, it is actually considered a scientific theory due to the vast amount of supporting evidence.

A hypothesis can become a theory if it is extensively tested and supported by empirical data. The theory of evolution has been tested and scrutinized for over a century, and the evidence continues to support its validity.


In conclusion, the theory of evolution is a well-established scientific theory that explains how and why living organisms have changed over time. While some may argue that it is still a hypothesis because it cannot be directly observed, the overwhelming amount of supporting evidence from various fields of science classifies it as a scientific theory.