This open textbook covers the most salient environmental issues, from a biological perspective. The text is designed for an introductory-level college science course. Topics include the fundamentals of ecology, biodiversity, pollution, climate change, food production, and human population growth.

Lecture slides for each chapter are available from https://drive.google.com/drive/folders/119oj6XXHnQMpwu_rCgczDFrZPMbqGN8W

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

Discuss the biogeochemical cycles of water, carbon, nitrogen, phosphorus, and sulfur
Explain how human activities have impacted these cycles and the potential consequences for Earth

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

Describe the basic ecosystem types
Explain the methods that ecologists use to study ecosystem structure and dynamics
Identify the different methods of ecosystem modeling
Differentiate between food chains and food webs and recognize the importance of each

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

Describe how organisms acquire energy in a food web and in associated food chains
Explain how the efficiency of energy transfers between trophic levels affects ecosystem structure and dynamics
Discuss trophic levels and how ecological pyramids are used to model them

Biology is designed for multi-semester biology courses for science majors. It is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand. To meet the needs of today’s instructors and students, some content has been strategically condensed while maintaining the overall scope and coverage of traditional texts for this course. Instructors can customize the book, adapting it to the approach that works best in their classroom. Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand—and apply—key concepts.