Here's why:
* Natural selection acts on variation: It favors individuals with traits that make them better suited to their environment. This means that over time, these beneficial traits become more common in a population.
* Evolution is the change in the genetic makeup of a population over time: Natural selection is the primary mechanism that causes these changes.
* Even seemingly "stabilizing" selection can lead to evolution: While stabilizing selection favors the average phenotype, it can still lead to evolutionary change by eliminating extreme variations, potentially changing the average over time.
It's important to understand that:
* Evolution is not always about "progress" or becoming "better": It's simply a process of adaptation to changing environments.
* Even in the absence of significant environmental change, populations can still evolve due to genetic drift and other factors.
It's also important to note that:
* Artificial selection is a human-driven process that can sometimes result in the loss of genetic diversity, which could make a population less resilient to environmental changes. However, this is not a form of natural selection.
In summary, natural selection is not something that prevents evolution; it is the driving force behind it. While different types of selection can lead to different evolutionary outcomes, all types of natural selection ultimately contribute to the ongoing process of evolution.
