Based on observations of species and fossils in the Galapagos Islands, Darwin came up with the theory of natural selection, which essentially said the fittest species would survive in the long run.
(Darwin; came up; ) (natural selection; essentially said; the fittest species would survive in the long run) Context(natural selection essentially said,List([105, 146))):(the fittest species; would survive; L:in the long run)
natural selection essentially said,List([105, 146))
Darwin natural selection the fittest species
came up essentially said would survive
the fittest species would survive in the long run
L:in the long run