Evolution explains the way organisms have adapted to changes in their environment in order to survive. This book looks at the theory of evolution, the mechanics of evolution on a general and molecular level, and whether there are patterns that might explain how plants and animals evolved. This series covers the fundamental life-science concepts of biology, ecology, evolution, genetics, cell biology, and life-forms, including humans. From the building blocks of cells and the basics of genetic theory through the structure, anatomy, and behavior of living organisms, this series tells the story of life in all its forms.