BEETLE ANALYSIS

Beetle statistical analysis

Beetle statistical analysis

A. Scientific Hypotheses

Is there any association between habitats and morphs of beetles? (1st scientific question)

H0: There is no correlation between habitat and morphs of beetles.

H1: There is a correlation between habitat and morphs of beetles.

Do the sexes differ in size and morph distribution (2nd scientific question)

For sexes and morph distribution

H0: There is a significant relationship between sexes of beetles and morph distribution of the beetles.

H1: There is an insignificant relationship between sexes of beetles and morph distribution of the beetles.

For sexes and size

H0: There is a significant relationship between sexes of beetles and size of the beetles.

H1: There is a significant relationship between sexes of beetles and size of the beetles.

B. Tables and summary statistics

1st scientific question

Correlations

Correlations

habitat

morph

habitat

Pearson Correlation

1

.904**

Sig. (2-tailed)

.000

N

475

475

morph

Pearson Correlation

.904**

1

Sig. (2-tailed)

.000

N

475

475

**. Correlation is significant at the 0.01 level (2-tailed).

The above table shows the correlation between habitat and morphs of the beetles. According to Pearson correlation, habitat and morphs of the beetles are strongly associated with each other. The correlation between morphs and habitat is 0.904 and the relationship is significant as p value is 0.000 which is less than 0.01. Hence, the null hypothesis is rejected.

2nd scientific question

NPar Tests

Descriptive Statistics

N

Mean

Std. Deviation

Minimum

Maximum

morph

475

3.19

1.039

1

4

elytronlength

475

4.0379

.26287

3.58

5.05

sex

475

1.65

.655

1

3

Kruskal-Wallis Test

Ranks

sex

N

Mean Rank

morph

female

212

107.12

male

215

343.50

unknown

48

343.50

Total

475

elytronlength

female

212

237.04

male

215

239.54

unknown

48

235.34

Total

475

Test Statisticsa,b

morph

elytronlength

Chi-Square

426.073

.056

df

2

2

Asymp. Sig.

.000

.973

a. Kruskal Wallis Test

b. Grouping Variable: sex

The above table of k independent sample test shows that morph has a significant relationship with the sexes of the beetles as p value is less than 0.05. The tabulated chi-square value for morph is 5.991 which is less than calculated value that is 426.073. Hence, the null hypothesis is accepted that is; there is a significant relationship between morph distribution and sexes.

Conversely, the p value of elytron length is greater than the significance value. The tabulated chi-square value (5.991) is greater than calculated chi-square value (0.056), thus, null hypothesis is rejected and alternative hypothesis is accepted that is; there is an insignificant relationship between size and sexes. C. Exploratory figures and graphs

Crosstab

Count

sex

Total

female

male

unknown

morph

typica

47

0

0

47

annuata

78

0

0

78

checquered

86

0

0

86

melanic

1

215

48

264

Total

212

215

48

475

The above graph shows that all the males are melanic and no male beetle has any other morph distribution, whereas, only one female has melanic morph distribution. the females have typica, annuata, and checquered morph distribution.

elytronlength (Binned) * sex Crosstabulation

Count

sex

Total

female

male

unknown

elytronlength (Binned)

<= 3.58

1

0

0

1

3.59 - 3.87

60

62

14

136

3.88 - 4.17

109

106

23

238

4.18 - 4.46

28

18

9

55

4.47+

14

29

2

45

Total

212

215

48

475

The above chart shows that males and females both have different sizes. There is no certain size limit for males and females. D. Statistical tests of ...