Natural selection happens in imperceptible increments over vast periods of time. That means that sometimes we can see traces of its path. It’s a misconception that organisms are perfectly formed and adapted to their environments. We can see the traces of natural selection, a slow and imperfect process, in vestigial structures. These are traits that are present in a species or some members of a species, but no longer have any function or value. Vestigial structures may only be present during the embryonic stage or they may be a permanent feature. In the past, they served an important purpose
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