The sizes of eyes in a population of spiders are monitored over several generations.The average eye size does not noticeably change, but the range of variation decreases.Assuming that no other evolutionary processes are occurring, what type of selection is most likely taking place?
A) Frequency-dependent
B) Stabilizing
C) Diversifying
D) Sexual
E) None of the above; selection is not operating.

Question

Quizplus · Accepted Answer

Stabilizing selection is likely taking place, as the average eye size is not changing (suggesting that there is no directional selection) but the range of variation is decreasing (suggesting that extreme variants are being selected against and the population is becoming more homogeneous).

The Sizes of Eyes in a Population of Spiders Are