Finch Beaks and Natural Selection By: Johnny B. Goode Warbler Finch

Darwin and Finches When Darwin explored the Galapagos Islands, he noticed many different types of finches on the different islands When Darwin explored the Galapagos Islands, he noticed many different types of finches on the different islands He came up with the idea that they came from the same ancestor and became new species through natural selection. He came up with the idea that they came from the same ancestor and became new species through natural selection. Each island had different finches from the others Each island had different finches from the others Warbler Finch

The Finches of the Galapagos Woodpecker Finch

Experiments in the Galapagos 1973 – Peter and Rosemary Grant begin studies on natural selection and finches in the Galapagos islands, specifically Daphne Island 1973 – Peter and Rosemary Grant begin studies on natural selection and finches in the Galapagos islands, specifically Daphne Island 1977 – wet season did not occur, resulting in huge drought 1977 – wet season did not occur, resulting in huge drought – More than 1,000 finches died Medium Ground Finch (G.fortis)

Experiments in the Galapagos After drought, there were more big G.fortis finches than small ones After drought, there were more big G.fortis finches than small ones Big finches can eat bigger seeds that small finches can’t Big finches can eat bigger seeds that small finches can’t – Being more flexible with type of food allowed the big finches to survive after the small finches ran out of food Medium Ground Finch (G.fortis)

Result of Drought on Finch Beak Size Small Tree Finch

Genetics and Finch Beak Size Before the drought, there was a wide variety of beak sizes in G.fortis, including big beaks. Before the drought, there was a wide variety of beak sizes in G.fortis, including big beaks. After the drought, there were more big- beaked finches left, and they reproduced to create a generation of big-beaked finches. After the drought, there were more big- beaked finches left, and they reproduced to create a generation of big-beaked finches. The finches with big beaks had genes that made them have big beaks and then their offspring had big beaks, too. The finches with big beaks had genes that made them have big beaks and then their offspring had big beaks, too. Vegetarian Finch

References Background photo: Background photo: – Allen, S. (n.d.). Birds of the Galapagos Islands & South America. Retrieved October 04, 2009, from Steve Allen Travel & Wildlife Stock Photography: – Allen, S. (n.d.). Birds of the Galapagos Islands & South America. Retrieved October 04, 2009, from Steve Allen Travel & Wildlife Stock Photography: Background sounds Background sounds – Medium Ground Finch: – Medium Ground Finch: Finch_Floreana1_ mp3http:// Finch_Floreana1_ mp3 – Small Tree Finch: – Small Tree Finch: – Vegetarian Finch: – Vegetarian Finch: canto.org/sounds/uploaded/XTVEPHMPPJ/Platyspiza_crassirostris_1979_02_22.mp3http:// canto.org/sounds/uploaded/XTVEPHMPPJ/Platyspiza_crassirostris_1979_02_22.mp3 – Warbler Finch: – Warbler Finch: – Woodpecker finch: – Woodpecker finch: canto.org/sounds/uploaded/XTVEPHMPPJ/Camarhynchus_pallidus_1979_02_22.mp3http:// canto.org/sounds/uploaded/XTVEPHMPPJ/Camarhynchus_pallidus_1979_02_22.mp3 Darwin and Finches Darwin and Finches – Zimmer, C. (2006). Evolution: The Triumph of an Idea. New York: Harper Perennial. Finches of the Galapagos Finches of the Galapagos – Experiments in the Galapagos Experiments in the Galapagos – Zimmer, C. (2006). Evolution: The Triumph of an Idea. New York: Harper Perennial. – Image: Explore Evolution. (n.d.). Retrieved October 04, 2009, from University of Nebraska State Museum: – Image: Explore Evolution. (n.d.). Retrieved October 04, 2009, from University of Nebraska State Museum: Result of Drought on Finch Beak Size Result of Drought on Finch Beak Size – Morris, T. (n.d.). Ecological Genetics: Adaptation and Natural Selection. Retrieved October 04, 2009, from Ecological Genetics:Adaptation and Natural Selection: – Morris, T. (n.d.). Ecological Genetics: Adaptation and Natural Selection. Retrieved October 04, 2009, from Ecological Genetics:Adaptation and Natural Selection: