Distinguish between relative and radiometric dating trouble updating my ps3 with 2 10
Contrast this with the torpedo shape that sharks and dolphins share; this similarity is useful in both groups.
And how does natural selection affect the way in which evidence concerning common ancestry should be evaluated?
Darwin addresses one of these two questions very succinctly in a passage from the Origin: …
adaptive characters, although of the utmost importance to the welfare of the being, are almost valueless to the systematist.
This is why the adaptive similarity is almost valueless to the systematist who is trying to reconstruct patterns of common ancestry.
In this passage, Darwin is saying that to determine whether a trait shared by two species is strong evidence that they have a common ancestor, one must be able to judge whether there was selection for the trait in the lineages leading to each.