Bird Beak Lab Conclusion

In this lab we asked the question: if natural selection occurs in a population, how do changes in selective pressures affect the evolution of that species?  We found that Darwin's two conclusions are indeed true. Individuals whose inherited traits help them survive, tend to leave more offspring. The tweezer beaked bird's easily maneuvered beak caused it to be the best suited for picking up rubber bands, macaroni, toothpicks. It produced 21 offspring in the first part, and produced 8 offspring in the second part, more than the scissor beaked bird, the binder clip beaked bird, and the spoon billed bird. This data supports our claim because the tweezer beaked bird, who's incredibly functional beak helped it survive, produced, by far, the most offspring among the bird population. We also found that it is true that the better traits of individuals become more common in populations over generations. The tweezer beak bird's offspring became more and more abundant as the simulation went on from year 1 to year 2 to year 3. This data supports our claim because the tweezer beak bird consistently collected the most food, collecting the most food in year 3. 

While our evidence supports our claims, there could been errors due to the difference size and strength of the hands of the people participating in the experiment. Some people are better at maneuvering their hand to use their given tool to pick up the food. Another possible error that could prove our claim incorrect is the fact that food seemed to be selected to specifically customize the abilities of the scissors, tweezers, and binder clip that could all pinch the items. This caused the simulation to not be completely accurate because if an organism, such as the spoon, could not collect any food in a certain area, then realistically, they would feel the need to emigrate to an area with food that suits their ability to collect the food. Even if one of the purposes of the experiment was to eliminate the spoon species, it was very obvious even before we even started that the spoon did not have any capability of picking up food. Due to these errors, in future experiment I would recommend collecting and recording the overall class data to average out the physical skill level of individuals and get more accurate results. I would also recommend adding a food of larger size to the experiment that could give the spoon at least somewhat of a chance to at least survive the first year. This would also make the results of the simulation less obvious from the start.

This lab was done to demonstrate Darwin's two conclusions regarding natural selection. From this lab I now fully understand the ways natural selection changes the dynamics in an ecosystem, which helps me grasp the simplicity, yet brilliantness of Darwin's findings. Based on my experience from this lab, I can now interpret the reasons for the difference in species I see when I go to natural history museums or read about animals such as wholly mammoths that have evolved into elephants today. The natural environment forced these organisms to adapt or die and the ones that stayed, changed their phenotype as a result.

<http://it.pinellas.k12.fl.us/Teachers3/gurianb/files/8041AE1EF3B946ABB522A47B70C43974.pdf>