Rivers change course, mountains rise and continents drift.
Explanation:
Rivers change course, mountains rise and continents drift are the geographic barriers that have led to the flinch speciation in the Galapagos because these barriers separated finch species from one another. Due to these geographic barriers, finch species have different body structure and features. These geographic barriers prevent two finch species from interbreeding with one another which leads to flinch speciation.
