Evolution is change in gene frequencies over time. This is a necessary requirement of heredity and natural selection.
Heredity is the passing of traits from parents to offspring.
Natural selection is the process by which some living things succeed in creating more offspring than others.
Once you have those two factors in a system, evolution is occurring.
Speciation occurs when the drift between two gene pools becomes great enough that individuals from the two pools can no longer create fertile offspring.
Contrary to your suggestion that this can't be observed, it can, and has been observed.
See this URL for more info: Five Major Misconceptions about Evolution
But the fact that you said "we haven't seen a fish turn into a frog" suggests your misunderstanding of evolution goes well beyond what I can provide in a forum post. There are many testable elements of the natural universe that are tied to evolutionary theory that go beyond what most people think of.
Heredity is the passing of traits from parents to offspring.
Natural selection is the process by which some living things succeed in creating more offspring than others.
Once you have those two factors in a system, evolution is occurring.
Speciation occurs when the drift between two gene pools becomes great enough that individuals from the two pools can no longer create fertile offspring.
Contrary to your suggestion that this can't be observed, it can, and has been observed.
See this URL for more info: Five Major Misconceptions about Evolution
But the fact that you said "we haven't seen a fish turn into a frog" suggests your misunderstanding of evolution goes well beyond what I can provide in a forum post. There are many testable elements of the natural universe that are tied to evolutionary theory that go beyond what most people think of.
BS Liberal Arts progress - 105/120
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