Answer :
Sexual dimorphism refers to differences in size or appearance between males and females of the same species. In this context, we are assessing whether a sample shows sexual dimorphism in head size.
Let's analyze the given options to find evidence that would support the claim of sexual dimorphism:
The average size of the male head is 170 cm while the average size of the female head is 166 cm.
- This indicates a small difference in average head size between males and females, but the difference is not substantial enough to conclusively support sexual dimorphism.
The average head size for males is 170 cm and the average head size for females is 155 cm.
- There is a more notable difference here, with males having a significantly larger average head size than females. This would support the claim of sexual dimorphism.
The range of head sizes for males is 180 to 170 and the range of head sizes for females is 140 to 176.
- Although the ranges overlap, the upper limit for males is higher, indicating potential size differences. However, overlapping ranges do not strongly support sexual dimorphism on their own.
There is no way to assess sexual dimorphism in head size.
- This is incorrect. We can assess sexual dimorphism by comparing average sizes and range overlaps.
The range of head sizes for females is 150 to 165 cm and the range of head sizes for males is 175 to 190 cm.
- This shows clear non-overlapping ranges between males and females, indicating significant size differences, which strongly supports the claim of sexual dimorphism.
Based on the analysis, the best pieces of evidence supporting sexual dimorphism in head size are options 2 and 5. Of these, option 5 shows the most clear evidence of sexual dimorphism due to the distinctly non-overlapping range of sizes.
