Answer:
Lizards that use interconnected burrows to avoid raccoons will likely survive more than those who do not use interconnected burrows and they will pass this trait to their offspring which will increase this trait in the population and will help the trait to become more common in the population.
As this trait will become more common than less lizards would be picked by raccoons which will the group living of lizards. This process of selecting more adapted individuals in a population is called natural selection.