How did birds develop different types of beaks?
Adaptive Radiation – Eg. When Charles Darwin was in the Galapagos islands, one of the first things he noticed is the variety of finches that existed on each of the islands. All in all, there were many different species of finch which differed in beak shape and overall size. This is adaptive radiation and natural selection at work. Darwin’s Finches These finches, better known as ‘Darwin’s Finches’ illustrated adaptive radiation. This is where species all deriving from a common ancestor have over time successfully adapted to their environment via natural selection. Previously, the finches occupied the South American mainland, but somehow managed to occupy the Galapagos islands, over 600 miles away. They occupied an ecological niche with little competition. As the population began to flourish in these advantageous conditions, intraspecific competition became a factor, and resources on the islands were squeezed and could not sustain the population of the finches for long. Due to the mechan