In part one of our lab, our claim was that "Individuals with better traits leave more offspring". The evidence of this occurrence is that the tweezer and spoon had 22 and 23 chicks respectively (shown on graph), while the scissors only had 14 chicks. This is because the tweezers and spoon were easier to use with the given materials and thus were the better trait, allowing them to leave more offspring.
Another claim of ours was that "Populations begin to look more like winners."The evidence of this occurrence is that the tweezer and spoon had 39% and 37% of the population, while the spoon only had 24% of the population. This is because the tweezers and spoon were the "winners" in terms of the amount of chicks they had and the quality of their traits were better then that of the scissors. This increase in the amount of chicks allows them to have a larger amount of the population and thus, the population reflects them.
In part two of this lab, we asked the question of "If natural selection occurs in a population, how do changes in selective pressures affect the evolution of that species?" Our hypothesis was that if natural selection occurs within a population and selective pressure mainly effects traits that are not suited for it, then only the traits that are suited to survive a certain selective pressure will continue the process of evolution. The scenario assigned to us was that we were only able to use 1/4th of our food source, which made food very scarce and allowed instruments that pick up large amounts at a time to survive. Our claim was correct since the tweezers and spoon were able to intake large quantities at a rapid pace, with a respective 12 and 11 chicks born between the two. On the other hand, the scissors, which take time to gain food, were unable to compensate in either loading capabilities of speed, and thus only had 7 chicks. This result is likely caused by how the traits adapted to the selective pressures, and those that were less suited had a lower chance of survival.
While our hypothesis was supported by the data, there have been errors due to first, the uneven partition of our food supply, and second, the differences in the techniques for using certain beaks. The cause of the uneven food partition was human error, as we partitioned it through the eye test rather than quantitatively partition it, which may have allowed for a wrong amount of food to be used in the test. This could have effected the number of chicks hatched and changed the effect of the selective pressure itself. The cause of the difference in technique was also human error. One example of this was the spoon, which was used by some to push food against a wall and collect it, which was easier that outright collecting food. The effect of this was that the number of chicks hatched for the spoon may have been altered due to an illegal advantage. Some solutions to these problems include using a scale or another type of quantitative measurement and to clarify instructions over the usage of the different beaks.
This lab was done to demonstrate the process of natural selection and two of Darwin's main principles, which are that individuals with better traits leave more offspring, and that populations begin to look more like winners. From this process I learned how different traits survive in a population, which helps me understand the concept of natural selection, where only certain traits are able to survive selective pressures and control the majority of the population. This relates back to the vodcast called "change, its all natural" where we learned about the basics of Darwin's conclusions and to 7th grade science, where we learned the concept of natural selection, but never experienced a life like example of it. based on my experience from this lab, I know how to create an experiment through the use of competition and how to change variables but still keep the same principle concepts.
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