Get started!

Stage 1
Answer 4 questions correctly in a row.

This passage describes shell color in grove snails.

a grove snail with a dark-colored shell

Some grove snails have light-colored shells, and others have dark-colored shells. Dark-colored shells absorb more light, so they heat up in the sun more easily than light-colored shells do.
Snails are more likely to survive when they are not too hot or too cold. So, grove snails that live in shady places tend to have dark-colored shells, and grove snails that live in sunny places tend to have light-colored shells.

The table below describes a possible population of grove snails at the start of a period of time and at the end of that period. The table shows shell color in the population at each point in time.

Complete the table.

Data about a population of grove snails
Point in time	Number with light-colored shells	Number with dark-colored shells	Percentage with light-colored shells	Percentage with dark-colored shells
Start	98	102	49%	%
End	893	57	94%	%