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Ancestral species are common on a certain hawaiian island. However, on the islands surrounding it derived species are more common. Does this phenomenon support dispersal or vicariance? Explain.
I think it supports dispersal, because it’s likely that the ancestral species originated on the first island and then through migration moved to the other islands, occupying slightly different niches and conditions and thus becoming different. I don’t think it would support vicariance because if an event broke up all the islands wouldn’t the species be completely different and not derived?