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Using this link (https://evolution.berkeley.edu/evolibrary/misconceptions_faq.php) as a guide, explain why each is incorrect with regards to evolutionary theory and the process of natural selection: ”Natural selection involves organisms trying to adapt to changing environment”; ”Survival of the fittest means that individuals who are stronger, healthier, faster and larger will have a better chance of survival”; ”All variations must serve some sort of adaptive purpose.”

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The theory of evolution is a complex topic full of misconceptions. These misconceptions can come from a misunderstanding of evolution that was taught in school or from the media. Other misconceptions may be deliberate attempts to misrepresent evolution and undermine public knowledge about the theory. Let’s look at each of the misconceptions more closely.

“Natural selection involves organisms adapting to changing environments.”

Whilst natural selection leads to the adaption of species over time, it is not due to organisms trying to adapt to changing environments. The adaption that occurs is a byproduct of natural selection. Natural selection is when a species that is well-suited to living in a particular environment thrives; likewise, species that are not suited to an environment die out. The species that survives might be successful because of a genetic variation—this genetic variation is created by a random mutation, not by what an organism wants or is “trying” to do. They either have the genes that make them good enough to survive and reproduce, or they don’t! An organism cannot consciously adapt to a changing environment.

“Survival of the fittest means that individuals who are stronger, healthier, faster, and larger will have a better chance of survival.”

In evolutionary theory, the term “fittest” doesn’t mean the healthiest, fastest, and strongest individuals. Fittest here simply means the organism that is best at passing on its genes to the next generation (through reproduction). Being “good” at reproduction doesn’t necessarily equate to being the biggest or strongest animal. For example, a bird might succeed at reproduction because it is more brightly colored and better at attracting mates than its stronger but duller-colored counterpart. So, survival of the fittest means that the animal that is the most successful in reproduction will “survive”—that is, pass on its genes to the next generation.

“All variations must serve some kind of adaptive purpose.”

It is tempting to look at all evolutionary variations of a species and see them as serving adaptive purposes. You might look at the shape of a leaf, the behavior of your dog, or your hair color and think it served an adaptive purpose evolutionarily. However, not all genetic variations serve an adaptive purpose. Some are quite simply chance results of history, others are byproducts of other characteristics, and other adaptions are outdated. That means that they may have once served an adaptive purpose, but they no longer do so due to changes in their environment. Other variations are “exaptations”—this means they serve a different purpose than their original, intended purpose. Feathers are a good example of this: they were first used for insulation and were later coopted for flight.

Finally, some genetic variations are due to a phenomenon known as “genetic drift.” This refers to the different mutations that occur across species due to their geographical distance. If a species, such as humans, spreads over vast areas of the earth, random mutations will occur to different groups in different areas. If they don’t serve adaptive purposes, then they are just neutral variations between species. Neutral theory notes that much of genetic variation is nonadaptive and neutral; it serves no evolutionary purpose.

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