The accompanying graph pg 53 on this pdf httpwwwzoologyubcca

The accompanying graph (pg. 53 on this pdf http://www.zoology.ubc.ca/~whitlock/bio300/bookchapters/WS_02.pdf) depicts a frequency distribution of beak widths of 1017 blackbellied 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?

Solution

a) the mode frequency is between 12 and 13 mm

b)

12-13 are 500 birds

c) the strategy that I would recommend will be to compare with the first peak and see the others peaks to see if there is a second peak

d) bimodal distribution