Their beaks were adapted to match the foods they ate.
The Galapagos Islands
Darwin realized finches on the Galapagos Islands were adapted to different regions
On each island of the Galapagos Islands
Finches, amomg others...
Since Darwin found many species of plants he found many species of finches. Those species, just like the warbler finch, were found on the Galapagos Islands.
That the finches were similar to the ones on the mainland, but had adapted to the island environment.
It is thought that the finches have a common ancestor. Separated on different islands, each island eventually produced different finches.
finches on the Galapagos islands, darwin noticed that on different island each beak of the finch was different depending on the food avalible on the different islands so darwin presumed that as each finch moved to these islands their beaks changed
beak structure
That the finches were similar to the ones on the mainland, but had adapted to the island environment.
The finches adapted to their available food on each island. If they ate only insects within trees, their beaks were long and pointed. If they ate seeds with a hard shell, their beaks became short and powerful. Darwin proved his theory of evolution based on the differences he observed among the finches on the different islands.
charles darwin