The accompanying graph depicts a frequency distribution of beak widths of 1017 black-bellied seedcrackers, Pyrenestes ostrinus, a finch from West Africa (Smith 1993).

a. What is the mode of the frequency distribution?

b. Estimate by eye the fraction of birds whose measurements are in the interval representing the mode.

c. There is a hint of a second peak in the frequency distribution between 15 and 16 mm. What strategy would you recommend be used to explore more fully the possibility of a second peak?

d. What name is given to a frequency distribution having two distinct peaks?

Transcribed Image Text:

Frequency 600 500 400 300 200 100- 0 10 12 14 16 Beak width (mm) 18