A group of lab rats escaped from a science laboratory. Most of the rats had white fur, but some had brown fur. They set up housekeeping in a field of hay. Some hawks found the group of lab rats and began to hunt them every day. Soon, most of the white rats were eaten, and only the brown rats were left in the field. What happened to the white rats?
1) They migrated to a different location.
2) They were eaten by hawks.
3) They changed their fur color to brown.
4) They found a new habitat.