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. Population for the Darwin Island finch increased to 495, while the Wallace Island finch increased to 496. On the 2nd experiment, the scientist decided to change the independent variable. The year would continue to start in 1997. The size of the finch beak will remain 12.00 mm. Precipitation will be changed to 9.0 cm for Darwin Island, and 5.0 cm for Wallace Island. If precipitation went down, the size of the finch beak would increase. In 2096, the beak size for the Darwin Island finch was 18.59 mm, while the beak size for the Wallace island finch increase to 18.18 mm.

The population increased to 351 for the Darwin Island finch, and 444 for the Wallace Island finch. On the 3rd experiment for Darwin Island, the independent variable was increased to 78.cm, while the independent variable for Wallace Island increased to 68. cm. The precipitation increase at Darwin and Wallace Island, indicated a decrease in beak size. The finch beak size in 2096, was measured at 10.72 mm. The decrease of the finch beaks at Wallace island measured at 11.61 mm. The population at Darwin Island increased to 682, while the finch population at Wallace Island increased to 660. Once the scientist finished analyzing the data collected they were able to determine if their hypothesis was correct or incorrect. The final results of the scientific hypothesis was proved to be incorrect. The scientist believed that if the precipitation was to increase at Darwin and Wallace Island, the finch beak would enlarge in size.

The data collected determined that the increase of precipitation, made resources more available to all the finch population. The increase of precipitation also decrease the size of the finch beak. Since resources were more abundant, the need for a larger beak was not necessary for survival. The data that indicated a decrease of precipitation, the finch beak grew larger. The finch population also decreased, because resources were not easily available to all the population. Since the discovery of a small population of finches, scientist have been able to determine that precipitation helped the finch population increase in size on Darwin and Wallace Island. If the environment failed to provide rainfall, the finches were able to adapt. During the periods of drought, the finches beak size would increase, giving them a likelier chance of survival for them and their offspring. Without an organism being able to mold himself to his environment, the possibility of survival for that creature is unknown.

References

Bell, J., Desharnais, B., Mason, Z., Quinn, R., Wolf, S., LaMar, M., Smith,
R., Daly, J., Zweier, L., McDearmon, J., Fogel, L. (2002). Evolution Labe [Multimedia]. Retrieved from Bell, J., Desharnais, B., Mason, Z., Quinn, R., Wolf, S., LaMar, M., Smith, R., Daly, J., Zweier, L., McDearmon, J., Fogel, L., University of Phoenix: BIO 101 website. Simon, E. J., Reece, J. B., Dickey, J. L. (2010). Essential biology with physiology. (3rd ed.). San Francisco, CA: Pearson/Benjamin Cummings.