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.

By the end of this section, you will be able to:Define species and describe how species are identified as differentDescribe genetic variables that lead to speciationIdentify prezygotic and postzygotic reproductive barriersExplain allopatric and sympatric speciationDescribe adaptive radiation

By the end of this section, you will be able to:Discuss the need for a comprehensive classification systemList the different levels of the taxonomic classification systemDescribe how systematics and taxonomy relate to phylogenyDiscuss the components and purpose of a phylogenetic tree

Species extinction is happening at an alarming rate according to scientists. In this lesson, students are asked to consider why extinction is a problem that we should concern us. They are taught that destruction of habitat is the main reason many species are threatened. The lesson explores ways that engineers can help save endangered species.

This activity illustrates the interrelationship between science and engineering in the context of extinction prevention. There are two parts to the activity. The first part challenges students to think like scientists as they generate reports on endangered species and give presentations worthy of a news channel or radio broadcast. The second part puts students in the shoes of engineers, designing ways to help the endangered species.

Students experience civil and environmental engineering by planning a housing development in an existing biome, while also protecting the native species that live there. They conduct research, draw plans, make brochures and give presentations, with each team having a member serving as a project manager, civil engineer, environmental engineer and graphic designer. The best designs creatively balance the needs and resources necessary to support both the native species and human infrastructure.

Students perform a macroinvertebrate survey to gauge the health of a local river. They collect water samples and count macroinvertebrates to learn how the health of a river's ecosystem can be determined by its river insect population.