Charles Robert Darwin was one of the founders of evolution. Other people who contributed to this were Jean-Baptiste Lamarck and Alfred Russel Wallace.
- Darwin Theory or Darwinism: This states that all species of organisms arise and develop through the natural selection of small, inherited variations (traits) that increase the individual's ability to compete, survive, and reproduce.
- Thomas Henry Huxley, for the purpose of economics, coined the word Darwinism in April 1860, in which he used it to illustrate the survival of the fittest in economic terms.
- Jean-Baptiste Lamarck was associated with the theory of inheritance of acquired characteristics (soft inheritance). He proposed the "Use and disuse of characteristics."
- Natural selection was coined by Alfred Russel Wallace and popularized jointly by Darwin in their joint publication in 1858.
- Natural selection is the process by which animals and plants with traits considered desirable by them are systematically favored for reproduction.
- Survival of the fittest is central to natural selection. Individuals that are more fit have a better chance or potential for survival.
Examples of natural selection:
- The sickle cell anemia have low fitness potential in the general population but the trait confers immunity to malaria. So in areas where malaria infection rates are high, it has a high fitness value in that population.
- Finches of the Galapagos Islands differ in the shapes of their beaks. The beaks of over 13 species is suited to its preferred food, suggesting that the beak shapes evolved by natural selection.
Natural selection can act on any inheritable phenotypic traits. The selection pressure can come from any aspects of the environment. This include sexual selection where the female organism chooses which male it prefers to mate with, or competition with same or other species for food or space.
There are different types of natural selection which I will discuss in the next post. Stay tuned!
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