These images from the Smithsonian Institution depict Nancy Knowlton's work with snapping shrimp in Panama. Knowlton found that the closing of the isthmus -- dividing the Pacific Ocean from the Caribbean -- resulted in new species of shrimp.

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:

Define biogeography
List and describe abiotic factors that affect the global distribution of plant and animal species
Compare the impact of abiotic forces on aquatic and terrestrial environments
Summarize the effects of abiotic factors on net primary productivity

This pathway explores the importance of biodiversity and human impact on the environment.

These pages are part of a site called "Evolution," that accompanies a textbook by the same name. Mark Ridley is the author, and in this section he discusses the evidence for evolution.

From the Evidence for Evolution Library at PBS, this is a short article about biogeography. The distribution of animals is one source of evidence for Darwin's descent with modification.