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:

Give examples of how the carrying capacity of a habitat may change
Compare and contrast density-dependent growth regulation and density-independent growth regulation, giving examples
Give examples of exponential and logistic growth in wild animal populations
Describe how natural selection and environmental adaptation leads to the evolution of particular life-history patterns

Explore a NetLogo model of populations of rabbits, grass, and weeds. First, adjust the model to start with a different rabbit population size. Then adjust model variables, such as how fast the plants or weeds grow, to get more grass than weeds. Change the amount of energy the grass or weeds provide to the rabbits and the food preference. Use line graphs to monitor the effects of changes you make to the model, and determine which settings affect the proportion of grass to weeds when rabbits eat both.