The figure below shows results of bristle number in Drosophila flies after 35 generations of artificial selection.This figure suggests that
A)bristle number has evolved beyond the original range of phenotypic variation for this trait.
B)after 35 generations of selection,populations no longer exhibit variation in bristle number.
C)natural selection cannot lead to large phenotypic changes.
D)at the end of the experiment,"high population" flies were unable to interbreed with "low population" flies.

Question

The figure below shows results of bristle number in Drosophila flies after 35 generations of artificial selection.This figure suggests that 
A)bristle number has evolved beyond the original range of phenotypic variation for this trait. 
B)after 35 generations of selection,populations no longer exhibit variation in bristle number. 
C)natural selection cannot lead to large phenotypic changes. 
D)at the end of the experiment,"high population" flies were unable to interbreed with "low population" flies.

Quizplus · Accepted Answer

The figure shows that the range of bristle number has shifted to higher values, beyond the original range of phenotypic variation. This suggests that artificial selection has successfully caused evolution in this trait.

The Figure Below Shows Results of Bristle Number in Drosophila