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:

Describe how ecologists measure population size and density
Describe three different patterns of population distribution
Use life tables to calculate mortality rates
Describe the three types of survivorship curves and relate them to specific populations

Overview of population size, density, and distribution.

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Paul Andersen explains how the world population has undergone exponential growth since the industrial revolution. Predicting the future world population is difficult because each country will grow at different rates. Age-structure diagrams and the demographic transition model can allow countries to plan for future growth. [10:18]

The CIA World Factbook provides an extensive page of information on Ecuador, a neighbor to Colombia. Includes information on this country's economy, climate, geographical location, government, size, and much more.

How environmental factors put limits on population sizes.

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Looks at how environmental factors put limits on population sizes.

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Review information on population size using this study guide.

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The author of the article admits having had a difficult time in the past when getting students to understand that samples need to contain a substantial portion of the population. Here, an activity is detailed to bring this important fact to understanding. Links are provided to the necessary handouts and materials. [Published 2004)

Learn bow the Grand River plated a role in the economy and culture of the people who lived along the river. [3:59]