Chapter 22 Quiz

Which of these conditions should completely prevent the occurrence of natural selection in a population over time?

All variation between individuals is due only to environmental factors

If x indicates the location of fossils of two closely related species, then fossils of their most-recent common ancestor are most likely to occur in which stratum?

C

Both ancestral birds and ancestral mammals shared a common ancestor that was terrestrial. Today, penguins and seals have forelimbs adapted for swimming. What term best describe the relationship of the bones in the forelimbs of penguins and seals, and what term best describes the flippers of penguins and seals?

homologous; analogous