Describe the role of variations in the adaptation and speciation of the galapagos island finches

Galalpagos Island finches have different shaped beaks which can consume different foods. The more food sources a number of species can tap into, the less scarcity they have to deal with within one--less competition, more food overall...and if that certain genetic trait helps a finch survive, that trait is going to be perpetuated by its offspring. (natural selection)

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