Natural Selection and Evolution
As we have already learned, natural selection is one mechanism for evolution. When most people think of evolution, they automatically think of natural selection. A lot of people believe that these two things are the same thing. However, that is not the case. Evolution can occur via different mechanisms that are not natural selection. While natural selection may be the most well-known mechanism of evolution, it is not the only one. We see evolution happen via genetic drift, migration, mutation, and others. Natural selection can occur and not lead to evolution.
Natural selection does not always mean evolutionary changes. We see this specifically when traits are not heritable. Say in a population, smaller body sizes are selected for you would assume that smaller body size would evolve over time. However, if body size is not heritable trait, evolution cannot occur. We saw this in our exercise from this week. The environment the cave mollies inhabited selected for small body sizes. However, this trait was unable to evolve because it could not be inherited.
This last question asks how selection can occur without natural selection. The one thing that comes to mind is different types of artificial animal breeding. Specific traits are selected for by the breeder and used to create the desired animal. This is not natural selection, but just selection.
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