Biology 2e is designed to cover the scope and sequence requirements of a typical two-semester biology course for science majors. The text provides comprehensive coverage of foundational research and core biology concepts through an evolutionary lens. Biology includes rich features that engage students in scientific inquiry, highlight careers in the biological sciences, and offer everyday applications. The book also includes various types of practice and homework questions that help students understand—and apply—key concepts. The 2nd edition has been revised to incorporate clearer, more current, and more dynamic explanations, while maintaining the same organization as the first edition. Art and illustrations have been substantially improved, and the textbook features additional assessments and related resources.

By the end of this section, you will be able to do the following:

Discuss the predator-prey cycle
Give examples of defenses against predation and herbivory
Describe the competitive exclusion principle
Give examples of symbiotic relationships between species
Describe community structure and succession

Communities are dynamic and change over time, and we can observe this process with particular clarity after a disturbance or on new land. Learn about primary and secondary succession, as well as pioneer species. [4:39]

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Ecosystems are "dynamic." This means that ecosystems change over time. Both natural forces and human actions cause ecosystems to change. Learn more about succession in this learning module produced by CK-12.

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