Natural Selection

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    When we think of natural selection, our mind usually goes to the belief in "survival of the fittest" as described by Charles Darwin. However, it is not always the fittest organisms in a population that pass their genes down to their children. The concept of "survival of the good enough" is actually a more accurate descriptor when it comes to natural selection. When it comes to finding a mate and reproducing, an organism doesn't need to be at the absolute top of its population, it just needs to be good enough to survive and reproduce. If an environment changes and results in a subsection of the population becoming better suited despite not necessarily being the 'fittest', they are simply good enough for the new environment and will continue to pass on their genes to the future population. 

    Additionally, in competitive species, the top of the population in terms of strength and fitness is constantly expending extra energy to maintain its alpha position. This extra time and energy expended has a negative effect on the amount of offspring it produces. A different organism in this population that does not have any extreme advantages or disadvantages has more energy to expend in finding a mate and reproducing. Thus, this organism is "good enough" for natural selection and will continue to pass its genes on. However, the weakest ones are unlikely to find a mate and won't produce many offspring. 

  


  An organism does not necessarily need to be the strongest or smartest to survive and produce offspring, it just needs to be "good enough" and the best adapted to its environment. The picture below demonstrates an example of this. While the larger light-colored moths are the best suited for the environment and better blend in with the light-colored trees of the environment, the smaller dark-colored moths have no particularly strong disadvantage. They can hide amongst the leaves and moss of the trees and continue to survive and pass on genes. However, after a forest fire, the trunks of the trees in the moths' habitat darken, causing a change in the environment. The light moths that previously had an advantage are now at a disadvantage and stand out to predators. 



Comments

  1. Jasmine Plata's Evolution BlogSeptember 22, 2024 at 8:53 PM

    I love the use of the moths coloration. I always wondered why odd color ones were able to survive but this makes sense to me now. Thanks!

    ReplyDelete
  2. AsheSeptember 29, 2024 at 2:49 PM

    I absolutely loved the photographs you used. Did you take them yourself?

    ReplyDelete

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