During his voyage, Darwin went to Galapagos Islands located in pacific ocean on western ghat of South America. There he saw an amazing diversity of creatures. While studying the finches present on islands. He found similarities in finches inhabitating in America and on island although these finches have difference in shape and structure of beak Such a difference were also observed in finches present on other islands
Of particular interest, small black birds later called Darwin's finches amazed him. He also observed many other varieties of finches in the same island. All the varieties, he conjunctuated evolved on the island itself. From the original seed eating habits, many other forms with altered forms arose, enabling them to become insectivorous and vegetarian

finches. This proces of evolution of different species in a queen geographical area starting from a point and radiating to other areas of geography is called adaptive radiation and Darwin finches represent one of the best example of adaptive radiation.