When it comes to the theory of evolution, two prominent names come to mind – Charles Darwin and Jean-Baptiste Lamarck. Both of these scientists came up with their own theories of evolution, but there are some key differences between them. In this article, we will explore the difference between Darwin’s theory of evolution and Lamarck’s theory of evolution.

Darwin’s Theory of Evolution

Charles Darwin is best known for his theory of natural selection, which states that organisms that are better adapted to their environment are more likely to survive and reproduce. This process leads to the gradual change in species over time.

One of the key aspects of Darwin’s theory is that it relies on variation within a population. This means that not all individuals within a species are identical.

Some may have traits that make them better suited to their environment than others. For example, a bird with a longer beak may be better able to reach food than a bird with a shorter beak.

Darwin also believed in the concept of common ancestry, which means that all living things share a common ancestor. According to his theory, over millions of years, small changes accumulate in species until they become so different from their ancestors that they are considered a new species altogether.

Lamarck’s Theory of Evolution

Jean-Baptiste Lamarck was an early proponent of the idea that species change over time. However, his theory differs from Darwin’s in several important ways.

Firstly, Lamarck believed in the inheritance of acquired traits. This means that if an organism developed a trait during its lifetime – such as increased muscle mass from exercise – it would pass this trait on to its offspring.

Lamarck also believed in the concept of use and disuse. He thought that if an organism used or didn’t use certain parts of its body enough, those parts would either become stronger or weaker over time. For example, he believed that giraffes developed long necks because they stretched to reach high branches, and over time, their necks became longer.

Differences between Darwin and Lamarck

The main difference between these two theories is that Darwin’s theory relies on natural selection and variation within a population, while Lamarck’s theory relies on the inheritance of acquired traits and the concept of use and disuse.

Additionally, Darwin’s theory supports the idea of common ancestry, while Lamarck’s theory does not. Darwin believed that all living things share a common ancestor and that small changes over time lead to new species. Lamarck did not believe in this concept – he believed that species could change but did not necessarily have a common ancestor.


Both Darwin’s theory of natural selection and Lamarck’s theory of inheritance of acquired traits were important contributions to our understanding of evolution. However, Darwin’s theory is widely accepted by scientists today due to its reliance on natural selection and variation within a population. While Lamarck’s ideas were influential at the time, they have largely been discredited by modern scientific research.