15. A certain species of snail shows variation in its shell coloring, from solid yellow shells to brown, banded shells. Birds are the main predator of this snail. A scientist
observes populations of this snail in various habitats. She hypothesizes that the
yellow-shelled snails are better camouflaged in grasslands than the brown-shelled
snails are.
A. Based on the scientist's hypothesis, describe how the percentage of
yellow-shelled snails most likely compares with the percentage of brown-shelled
snails in grasslands.
B. Assuming the scientist's hypothesis is correct, explain how natural selection could
have acted over time to produce the relative percentages of snails you described
in part (A)
C. Explain the reasoning that supports the scientist's plan to study the bird
population sizes.