The original Darwin's Finches on Galapagos islands was

Darwin in Galapagos islands observed an amazing diversity of creatures. Of particular interest, small black birds later called Darwin's Finches amazed him. He realised that there were many varieties of finches in the same island. All the varieties, he conjectured, evolved on the island itself. From the original seed eating features, many other forms with altered beaks arose, enabling them to become insectivorous and vegetarian finches.