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:

Identify significant threats to biodiversity
Explain the effects of habitat loss, the introduction of exotic species, and hunting on biodiversity
Identify the early and predicted effects of climate change on biodiversity

In both macroeconomics and microeconomics principles courses, economists teach the virtue of markets as an allocative mechanism. But markets sometimes fail. This example allows students to simulate the market failure associated with a common property resource, a salmon fishery, and evaluate ways to control fishing. The simulation also shows the distributional results of different allocative mechanisms. The simulation was developed by Paul Romer at Stanford University and is available on the Aplia web site.

This lesson introduces students to the "Tragedy of the Commons," an extended metaphor for problems of shared environmental or man-made resources that are overused and eventually depleted. In this metaphor, shared resources are compared to a common grazing pasture, or commons, on which any dairy farmer can graze as many cows as he/she wishes. [31:34]