A proficient engineer can easily design skeletal structures that are more functional than those currently found in the forelimbs of such diverse mammals as horses, whales, and bats. Which of the following statements best explains why the actual forelimbs of these mammals do not seem to be optimally arranged?
A) Natural selection has not had sufficient time to create the optimal design in each case, but will do so given enough time.
B) In many cases, phenotype is determined by genotype and the environment.
C) Although we may not consider the fit between the current skeletal arrangements and their functions excellent, we should not doubt that natural selection ultimately produces the best design.
D) Natural selection is generally limited to modifying structures that were present in previous generations and in previous species.

Question

Quizplus · Accepted Answer

Natural selection works by modifying existing structures rather than creating new ones from scratch, which explains why the current forelimbs of these mammals may not seem optimally arranged according to human engineering standards.

A Proficient Engineer Can Easily Design Skeletal Structures That Are