Darwin's Galapagos Finches

The story of Darwin's Galapagos finches is a nice example of adaptive radiation (where a stock  diversifies into a number of species, exploiting different life-styles or foods). Genetic information has confirmed that the varied finches are, in deed, monophyletic (from the same stock) but there is still the interesting question of where the birds came from to colonise the volcanic islands as they emerged from the sea and cooled (https://www.theguardian.com/science/2018/jul/30/origin-of-the-species-where-did-darwins-finches-come-from). It was generally assumed from they were blown across from Equador (the nearest mainland location) but some authorities have suggested origins as far as the Caribbean. Genetic techniques may well also answer this question.