Wendy Chavez
Principals of Biology/BIO 101
12/10/2012
Michael Erickson
University of Phoenix
Evolution of the finch on Darwin & Wallace Island
A small population of finches have been discovered on Darwin and Wallace Island. The population is 200 finches at Darwin Island, and 200 finches at Wallace Island. The year is 1997, and scientist measured the finch beak size from both Darwin and Wallace Island. The finches from both island, showed an average beak size of 12.0 mm. Precipitation on both Darwin and Wallace island average 20.0 cm. Scientists want to determine if precipitation was to increase, would the finch beak increase in size? In this lab study, scientist will be measuring the amount of precipitation within the discovery of the finch on Darwin and Wallace island, and collect data to prove that the finches evolved a larger beak due to the increase of rainfall.
To determine if the beak enlarged in size with the increase of rain fall, scientist will travel to Darwin and Wallace Islands to collect samples. The samples being collected will be the average size of a finch beak, and the average amount of precipitation in the region. The dependent variable that will be measured is the finch beak size. The independent variable that will be changed is precipitation. By changing the independent variable, the scientist will be able to determine if rainfall has an effect on the bird’s beak size.
The average beak size is 12.0 mm, while precipitation averages 20.0 mm at Darwin and Wallace Islands. The data from the samples were input onto an excel spread sheet, which calculated the data for the next 100 years. If the rainfall was to average 20.0 cm for the next 100 years, the finch beak size would increase. If the precipitation continued to average 20.0 cm, by 2096 the finch from Darwin Island would grow a beak of 18.5 mm. The finch from Wallace Island, would grow a beak of 18.21 mm.