The Grants' work on natural selection would have been impossible to complete if the traits they examined were
A) modified by the environment during the bird's lifetime.
B) adapted to particular environmental conditions.
C) completely heritable.
D) present to some degree in all finches.

Question

Quizplus · Accepted Answer

If the traits were modified by the environment during the bird's lifetime, it would make it difficult to determine if the trait was truly heritable or if it was simply a result of environmental influence. Natural selection acts on traits that are genetically determined and inherited, so it is important to focus on traits that are completely heritable.

The Grants' Work on Natural Selection Would Have Been Impossible