In 1909 the Danish botanist Wilhelm Johannsen did a number of studies of the inheritance of seed weight in the bean Phaseolus vulgaris. Below are the data from one of these experiments in which Johannsen compared the weights of the parent seed to that of the progeny within pure breeding line #13. The parental seeds were classified as 27.5, 37.5, 47.5 and 57.5 cg in weight. From the information given, do different sizes of parent seeds lead to different sizes of offspring seeds? What do the results indicate about the cause of variability in parent sizes and progeny sizes? Remember all individuals are from the genetically pure line #13. These data meet the assumptions of parametric statistics.
|
Parental
weight
|
Number of progeny of beans in 9 size categories
|
|
22.5
|
27.5
|
32.5
|
37.5
|
42.5
|
47.5
|
52.5
|
57.5
|
62.5
|
|
27.5
|
0
|
1
|
5
|
6
|
11
|
4
|
8
|
5
|
0
|
|
37.5
|
1
|
2
|
6
|
27
|
43
|
45
|
27
|
11
|
2
|
|
47.5
|
0
|
5
|
9
|
18
|
28
|
19
|
21
|
3
|
0
|
|
57.5
|
0
|
1
|
7
|
17
|
16
|
26
|
17
|
8
|
3
|