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Stage 1
Answer 4 questions correctly in a row.

Read this passage about two inherited traits in rock pocket mice.

a rock pocket mouse with brown fur

Rock pocket mice are small desert rodents that live either on sand and light-colored rock or on black lava rock. A rock pocket mouse may have either brown fur or black fur.

A mouse's fur color can help it hide from predators. For example, a mouse with brown fur can blend in with light-colored sand and rock, and a mouse with black fur can blend in with black lava rock.

The graphs below describe fur color in an isolated population of rock pocket mice at the start and end of a time period long enough for natural selection to occur. At the start of this time period, the rock pocket mice's environment changed.

Describe how the rock pocket mouse population changed over this time period. Use the theory of natural selection to construct a possible explanation for this change.

The percentage of mice with black fur in the population. This suggests that mice with brown fur were likely to survive and reproduce than mice with black fur. This may have occurred because there was light-colored rock than black lava rock after the population's environment changed. So mice with brown fur were more likely to be predators.