SAT Subject Biology Practice Question 340: Answer and Explanation
A population of birds (Population A) on a remote, isolated island is studied to determine beak length. The resulting data are plotted in Figure 1.
Suppose that 200 years later, the beaks of the birds on the island were again measured (Population B). The data, when plotted, yielded a graph as in Figure 2.
What is the average beak length (in cm) of the birds in Figure 1 ?
A. 30 cm
B. 15 cm
C. 5 cm
D. 3 cm
E. 1 cm
Correct Answer: D
D The question asks for the average beak length in cm, but the graph gives it in mm. Average beak length is 30 mm. 10 mm = 1 cm; therefore, 30 mm = 3 cm. Read the questions carefully!