Natural Selection Lab Report

Natural Selection Lab Report

Introduction:

The scientist and explorer, Charles Darwin, first proposed the idea of Natural Selection during the Nineteenth-century, when the exposure of the concept of evolution was first brought to light. Even though Darwin did not think of this idea first, he carried out a very important investigation about this subject that was essential for he theory of the evolution. His theory was based on the observations he took from the Galapagos Island and the Finches. Darwin observed that the same species developed different beaks along the Galapagos Islands in order to suit their circumstances and environments. In other words, they evolved in order to adapt and survive in their corresponding environment.
That was what Darwin concluded, and according to Dennis O´Nell, Darwin came to define the concept “survival of the fittest” as “the variation already existed and that nature just selected for the most suitable beak shape and against less useful ones” [O´Nell, 2013]. As seen in Figure 1.1, its clear the different shape and variations that Darwin saw along the same species of birds, and the ones that are suit the best their environment, are the ones that have better chances of surviving. From this idea about evolution, the experiment that is going to be preformed deals with the idea of “Survival of the fittest”.
Therefore, the experiment consists of using eating utensils, such as the spoon, fork, and knife as the beaks of the finches, and from there, which kind of beak is more capable of getting more food, in this
case, its going to be represented by a variation of beans.

Materials:

5 spoons
5 forks
5 knifes
100 red beans
100 white beans
100 black beans
100 pinto beans
1 timer

Method/Procedure:

First collect the materials needed in order to complete the lab. Separate 100 beans of each kind (red, white, black and pinto) and place them in cups. Then, pour the 400 beans in a surface. Give each participant a spoon, fork or knife. Place a plastic porch in front of each individual. Follow directions of the teacher, or time 45 seconds with the stopwatch. During the 45 seconds, collect as many beans as possible and place them in the cup. Record. Repeat this process three more times and record data.

Summary: As seen on the data collected, there is a clear decadence of the Knife-billed bird population since 18 of the 19 Birds died, as seen on the Table of Total bird Deaths and Births. On the extreme opposite, the Spoon-billed bird population actually reproduced, and doubled its population since they started with 22 birds, and ended with a total of 48 birds after four years. The only type of bird that didn’t change drastically throughout the experiment was the Fork-Billed bird, which its population decreased from 21 birds to 9 throughout the experiment. The population growth is also reflected on the amount of beans eaten individually by every species, as seen on the Total Bean Eaten Table. With an average of 4156 beans in the four years, we can see that the Spoon-billed birds consumed in average 1075 beans. The Fork-Billed beans ate in average of 880 beans and the Knife-Billed birds consumed in average 172 beans. Spoon-billed birds showed a large growth in their food consumption, meaning that these became the species with the predominant population. Fork-Billed bird population, didn’t fall far behind, yet spoon-billed birds still had a greater advantage. The Knife-Billed birds consumed less; therefore they were the less effective for eating beans.

Population of Birds After Four Years
Population of Birds After Four Years
Data Processing:

Population Amount
Population Amount

Time in Years
Time in Years

Figure 1.

The graph “Population of Birds After Four Years” demonstrates that the Spoon-Billed bird population is in growth of a rate of 10 people per year, while the population of Knife-Billed birds decreases drastically by around 10 people within a year, at the end there’s only 1 person left. While the Fork-Billed population barely increases after the first year, and then starts decreasing throughout years 3 and 4.
Time- in Years
Time- in Years
Total Bean Consumtion per Year
Total Bean Consumtion per Year
Beans Consumed
Beans Consumed

Figure 2.

On the Total Bean Consumption per Year graph you can see that the predominant bird species is the Spoon-Billed bird since you can see the other two species declining and becoming weaker since the Spoon-Billed are starting to dominate the food resources, in this case, the beans.

Conclusion:

In conclusion, the data collected supports the theory of evolution of Charles Darwin.
This theory deals with the concept of “Natural Selection” which means, according to the Biology Online definition: “a process in nature in which organisms possessing certain genotypic characteristics that make them better adjusted to an environment tend to survive, reproduce, increase in number or frequency, and therefore, are able to transmit and perpetuate their essential genotypic qualities to succeeding generation” ["Natural Selection", 2013]. This data supports this idea because this experiment was support to redo what Darwin observations during his expedition to the Galapagos Islands with the Finches birds, and their distinctive beaks depending on their environment. As mentioned in the Article of Natural Selection from the Michigan University “natural selection is the cornerstone of evolutionary theory. It provides the mechanism for adaptive change”["Natural Selection", 2013]. And as seen on the data, the bird species that wasn 't favored was the Knife-billed bird since they got extinct after the third year, and this is because their `beaks´ didn 't give them what they needed in order to survive. On the contrary, the Spoon-billed bird where able to even grow their population because of their physical characteristics of having a `wider beak´ to collect the beans. And for the Fork-Billed population, it kept being constant, with no growing or shrinking population. Therefore, going back
to Darwin´s theory, each beak changes and reform itself in order to make surviving easier, just as the concept of “Survival of the fittest” describes. The animal that has the best physical characteristics in order to suit best its environment, it 's the animal that it’s going to have the best chance to survive. Applying this idea to the experiment, the beak that is going to predominate it’s going to be the one of the Spoon-Billed population.
This lab gives any student a wide understanding of the theories of Darwin, and we actually had the opportunity to see these theories in practice with us as the subjects being tested. This lab made a very good representation of what is the idea of Natural Selection, and Survival of the fittest. As well, this lab could improve if it was made among more people, in order to have more variety among the results and making the data be more accurate since the populations consist of large amounts of individuals.

Bibliography:

O´Nell, Dennis. "Early Theories of Evolution: Darwin and Natural Selection." Early Theories of Evolution: Darwin and Natural Selection. N.p., n.d. Web. 13 Mar. 2013.

"Natural Selection." - Definition from Biology-Online.org. Biology Online, n.d. Web. 13 Mar. 2013.

"Natural Selection." Natural Selection. University of Michigan, 10 Oct. 2010. Web. 13 Mar. 2013.

Dawkins, R. 1989. The Selfish Gene. Oxford: Oxford University Press.