Evolution Lab 1: The Evolutionary Pattern of Beans and Beads by Brian Tran, Prach Techameena and Anh Nguyen

Hypothesis: There is a change in allele frequency of beads over 10 generations.

Prediction: If the hypothesis is true, then the allele frequency of generation 10 will be different from the allele frequency of generation 1.

Figure 1: The allele frequency represented by the number of beads in Population A over 10 generations. Red beads died off after nine generations. Clear beads started off and ended with the highest population number. The navy beads had a sharp decline  from generations one to three, but didn't end up dying off. The white beads steadily increased until generation seven and then steadily declined until generation ten.

Figure 2: The allele frequency represented by the number of beads in Population B over 10 generations. Navy beads had the highest population in all generations except in generation one. Clear beads increased over the first two generations and then decreased between generations three through five and then stayed constant for four generations before finally decreasing over generations nine and ten. The red beads started off decreasing until generation three, where it increases from generations four to ten. White beads steadily decreased in the first five generations and then fluctuated for the rest of the generations.

In comparing Population A and Population B, the majority number of beads in generation 10 were different. In Population A, the majority goes to clear beads, while in Population B, the majority goes to navy beads. Also, in Population A, red beads died off on generation nine, while clear beads got close in Population B, but never died off. All of these population changes were random, since the beads don't have a shape or size advantage over each other.

Chi Squared Table for Population A

Beads	Expected, e	Observed, o	o-e	(o-e)^2/e
Red	11	0	11	11
White	11	16	5	2.3
Blue	12	14	2	0.3
Clear	16	20	4	1
Total	50	50		14.6 = chi-square

Table 3: The calculations for Chi Squared for Population A

Chi Squared Table for Population B

Beads	Expected, e	Observed, o	o-e	(o-e)^2/e
Red	14	17	3	0.64
White	14	8	6	2.57
Blue	13	22	9	6.23
Clear	9	3	6	4
Total	50	50		13.45 = chi-square

Table 4: The calculations for Chi Squared for Population B. 

The null hypothesis is there is no change in the population throughout each generation. The critical value was 7.82 and both bead populations chi square values are greater than the critical value. Thus, the null hypothesis was rejected.

Conclusion: Our prediction was correct because the data that we collected and calculated chi square with shows that there was change in each generation of both bead populations. Moreover, we believe that this change is an example of genetic drift. The reason for this is because there was no variety that made one bead stand out in shape between the different colors.