Glossary

A scientific theory that explains how new species come about through many small adaptations over time.  Animals adapt to their environment to better survive and pass on their genes.  Over millions of years, these adaptations build up, creating new species.  There are four main points to evolution:

1. Within each species, individual animals are all different from one another.  Scientists call this variation.

2. Animals produce far too many offspring for them all to survive.  (Think about what would happen if every chicken egg in the grocery store hatched!)

3. Animals must compete with one another for food, shelter, and a mate.  There's only so much to go around.

4. The animals whose variations best help them win the food, shelter, and mates are the ones who are able to survive and pass their genes on to the next generation.