Introduction
The relationship between predator and prey can be determined by various factors .This can be due to phenotypic characteristics or, it can be due to environmental conditions and adaptations. The individual picking the colors could have a very keen eye for one color or not be biased, and pick any color. Some prey may be on an equal scale or some may be more susceptible, depending on the predator. The purpose of this experiment was to see if the results were due to chance, and the effects of predation as selection pressure. The independent variable in the experiment was the phenotypes of the Dottus variegates. The dependent variable would be the number of each Dottus variegates selected by the predator, or the phenotype frequency. Additionally, it was hypothesized that the phenotypes of Dottus variegates have no effect on the numbers of each phenotype selected by the predator.
Methods
In this experiment, a trio of personnel followed various steps as follows. The controls were determined to be the person of each role, the other control was the expected number of dots collected. Person number one is the predator. Person number two is responsible for scattering the Dottus variegatus organisms across the board. Person number three then collects the prey from number one and keeps count until 25 dots have been collected. One-hundred dots should be placed across the board in various areas. The predator will then turn away from the board, only to turn back around after a few seconds, and choose its prey. The newly selected prey will then be given to person number three. Person number two will then keep track of each one selected. This process will be repeated twenty-five times. The number of each phenotype will then be recorded in Table 9.7. The total should then be calculated in each of the three column, which include, number collected, number expected (which is continuous) and number surviving. The sum of column A and B should be 25, and the sum for column C should be 75, totaling 100. To obtain the number of excepted, one should divide the total number collected by the number of phenotypes, which would be 2.5. Additionally, the data was then collected and distributed to each of the remaining columns. Furthermore, a Chi square analysis was completed. The Purpose of composing a Chi square analysis was to determine whether or not the results were due to solely to chance alone.
Results
Table 9.7 – Data Table for Dottus variegatus Experiment
Color
# Collected A
# Expected B
# Surviving C
1. Light Pink
3
2.5
7
2. Orange
1
2.5
9
3. Yellow
5
2.5
5
4. Purple
4
2.5
6
5. White
1
2.5
9
6. Light Blue
0
2.5
10
7. Green
4
2.5
6
8. Clear
0
2.5
10
9. Blue
2
2.5
8
10. Hot Pink
5
2.5
5
Total
25
25
75
Figure 1.0- This table describes the different colors collected, as well as the expected numbers of each phenotype, and the number that survived. Column A was calculated by separating each Dottus variegatus in groups by their phenotype of coloration and then tallied with a sum of 25. Column B was deliberated by using the total number collected, which is 25, and then dividing it by the number of phenotypes, which was 10, making it 2.5 for each color. Column C was calculated by subtracting the number of original Dottus variegatus, which is ten for each color, from the collected, totaling to 75.
Table 9.8—Chi square analysis for Dottus variegatus Experiment
Observed # – Expected #
A-B from Table 1
(Observed # – Expected #)^2
(Observed # – Expected #)^2 / Expected #
.5
.25
.1
1.5
2.25
.9
2.5
6.25
2.5
1.5
2.25
.9
1.5
2.25
.9
2.5
6.25
2.5
1.5
2.25
.9
2.5
6.25
2.5
.5
.25
.1
2.5
6.25
2.5
Sum of Chi Square Values = 13.8
Figure 2.0 –The table above is a Chi square analysis, which uses a comparative method to determine the numbers observed with the results expected to be produced solely by chance. The first column represents the observed number, which is column A from table one, minus the expected number which is column B from table 1. The second column represents the observed number minus the expected number squared. The third column is the number from column two divided by the expected number, which is always constant. Lastly, the Sum of the Chi square values is represented by the bottom right area, this is all of the values from column three totaled. The value of 13.8, means now that it lies between .05 and .5 on the Chi square distribution table, meaning that the null hypothesis, of no effect not rejected.
Discussion
The results listed above lead the hypothesis that was previously proposed to not be rejected. This means that the value of 13.8 indicates that the phenotypes of Dottus variegatus, have no effect on the numbers of each phenotype selected. As well as the fact that the effects of predation as a selection pressure, could be due to chance. “Phenotypic plasticity occurs at the individual level by changing the phenotype depending on the environment” (Greiner, Barre, Litrico, 2016). This can resemble the fact that the environment plays a key role in the predation effect. That it does not always rely on phenotypes, which occurs at the individual level and that some phenotypes are changing and therefore the results could be skewed due to environmental effects, instead of phenotypes. “The hunt success of predators is affected by inter specific exploitation of competition and interference.”( Severtsov, Shubkina 2015). This quote can verify the fact that in a specific predator-prey relationship, there may or may not be a level of competition there, or a need for resources, as in a shortage so any of the phenotypes could have been eaten, due to the fact that there was not a dire need for them at that moment. “Studies have shown that variations in color and marking of many insects affect predation success by birds” (Mader, 2016) This is stated, however due to the results as shown in figure 9.7, even the green phenotype was still just as much effected as the yellow or the hot pink color. This is important to the fact that the map contained an array of colors, but was filled heavily with green trees. Yet, the green Dottus variegatus, was still eaten. Which can conclude that phenotypes in fact do not have an affect on the numbers of phenotypes selected. It could be due to phenotypes that have nothing to do with coloration, in nature, it could be due to the physical agility and many other factors, that were not taken into account in this experiment.
Literature Cited
S. Grenier, P. Barre, and I. Litrico, “Phenotypic Plasticity and Selection: Nonexclusive Mechanisms of Adaptation,” Scientifica, vol. 2016, Article ID 7021701, 9 pages, 2016. doi:10.1155/2016/7021701
Severtsov, A. S., & Shubkina, A. V. (2015). Elements of ecology.