Difference Between Darwinism and Evolution

The main difference between Darwinism and evolution is that Darwinism is a theory of evolution based on natural selection whereas evolution is the change in the genetic composition of a population over successive generations. Darwinism describes organic evolution, which results in speciation. But, evolution is driven by natural selection, gene flow, genetic drift, inbreeding, hybridization or mutation. 

Darwinism and evolution bring phenotypical changes in the individuals of a particular population with time. Both occur in response to the long-term changes of the environment. 

Key Areas Covered 

1. What is Darwinism
     – Definition, Features, Examples
2. What is Evolution
     – Definition, Features, Examples
3. What are the Similarities Between Darwinism and Evolution
     – Outline of Common Features
4. What is the Difference Between Darwinism and Evolution
     – Comparison of Key Differences

Key Terms: Darwinism, Evolution, Macroevolution, Microevolution, Natural Selection 

What is Darwinism 

Darwinism refers to the theory of evolution of species by natural selection advanced by Charles Darwin. Natural selection is one of the main mechanisms that drive evolution. It aids the individuals of a particular population to adapt well to their environment. This gives them a better chance at survival and the ability to produce more offspring within that environment. The four concepts of the Darwin’s theory are variation, inheritance, high rate of population growth, and differential survival and reproduction. Genetic variations occur among the individuals within the same population due to mutations, gene flow, and genetic drift. Secondly, the reproductive potential of those individuals varies. Then, the differential reproduction promotes the inheritance of a set of characteristics that are hence selected. In this way, the best-fitted characteristics or phenotypes accumulate over generations. 

Figure 1: Natural Selection

What is Evolution 

Evolution refers to the change in the heritable characteristics of biological populations over successive generations. In addition to natural selection, phenomena like mutations, gene flow, and genetic drift also drive evolution. Inbreeding and hybridization are sexual selection methods that lead to evolution. The grand idea about evolution was first fully expounded by Charles Darwin. Evolution leads to the continuous branching and diversification of organisms starting from a common ancestor in a process called speciation. Evolution takes place in both small scale (microevolution) and grand scale (macroevolution). Mutations, gene flow, genetic drift, and natural selection are responsible for microevolution. The four patterns of macroevolution are stasis, character change, speciation, and extinction. Some species do not change over a period of time and exist as live fossils, which is called stasis. Analogous or homologous structures emerge in character change. In speciation, either geographical or reproductive isolation of individuals in a population lead to the emergence of new species. Most species become extinct during evolution. The speciation of Hominini from 10 Mya to present is shown in figure 2. 

Figure 1: Speciation of Homonini

Similarities Between Darwinism and Evolution 

• Darwinism and evolution bring changes to a particular population. 
• Both occur in response to the long-term changes of the environment. 
• Each and every population on the earth undergoes Darwinism and Evolution. 
• Extension or death is the result of both. 
• Extension leads to speciation. 

Difference Between Darwinism and Evolution 

Definition 

Darwinism: Theory of evolution of species by natural selection advanced by Charles Darwin

Evolution: Change in the heritable characteristics of biological populations over successive generations 

Significance 

Darwinism: A theory of evolution 

Evolution: Change of a particular population with time 

Process 

Darwinism: Natural selection 

Evolution: Natural selection, gene flow, genetic drift, inbreeding, hybridization or mutation 

Mechanisms 

Darwinism: Genetic variations arise by the mechanisms of sexual reproduction such as mixing of alleles and crossing over

Evolution: Occurs through overproduction, genetic variations, the struggle for existence, survival of the fittest, and natural selection 

Observation  

Darwinism: Observable changes occurs within a short period of time 

Evolution: Takes millions of years to make an observable change 

Examples  

Darwinism: Light and dark peppered moths, long neck and short neck giraffes, and light brown deer mice  

Evolution: Disappearance of tail bones of humans, decrease in human head size, and shortening of the pinna  

Conclusion 

Darwinism is the theory that describes the proceeding of evolution by means of natural selection. Evolution is the process that gives rise to phenotypical changes within a particular population due to the long-term changes of their environment. It occurs through natural selection, gene flow, genetic drift, inbreeding, hybridization or mutation. This is the difference between Darwinism and evolution.

Reference:

1. “Darwin’s Theory Of Evolution.” Darwin’s Theory Of Evolution, Available Here
2. “What Is Evolution?” Facts, The Public Engagement Team at the Wellcome Genome Campus, 17 Feb. 2017, Available Here

Image Courtesy:

1. “Natural selection” By OrientationEB – Own work (CC BY-SA 4.0) via Commons Wikimedia 
2. “Hominini lineage” By Dbachmann – Own work (CC BY-SA 4.0) via Commons Wikimedia