Ch 21: Evolution & Biodiversity

About This Chapter

Prepare for a test that covers evolution and biodiversity using this chapter's helpful study resources. Engaging lessons, mini-quizzes and a practice exam can strengthen your comprehension of evolution and biodiversity and build your confidence before taking your test.

Evolution & Biodiversity - Chapter Summary

Review entertaining lessons in this chapter from home or on the go to gain greater insight into the basics of evolution and biodiversity. This self-paced chapter offers in-depth analyses of topics like speciation, natural selection and adaptation. After studying the lessons, you will be ready to do the following:

  • Describe Charles Darwin's impact on science and discuss his theory of natural selection
  • Explain why natural selection acts on physical traits and not genetic makeup
  • Discuss the impact of natural selection on animals and explain what adaptations tell us about evolution
  • Define and share examples of speciation
  • Differentiate between allopatric speciation and sympatric speciation

Don't let a busy schedule get in the way of your ability to study evolution and biodiversity. Around-the-clock computer and mobile access to the lessons enables you to study whenever and wherever your schedule permits. Multiple-choice quizzes paired with the lessons let you quickly gauge your knowledge of the concepts they cover. If you hit a snag or need help clarifying topics examined in this chapter, feel free to submit them to our experts via the Dashboard.

6 Lessons in Chapter 21: Evolution & Biodiversity
Test your knowledge with a 30-question chapter practice test
Darwin's Theory of Natural Selection: Overview

1. Darwin's Theory of Natural Selection: Overview

In this lesson, you'll be introduced to Charles Darwin and his theory of natural selection. You'll also learn a bit about how his ideas impacted science, popular understandings of human origins, and the debate his theories have sparked.

Why Natural Selection Acts on Phenotype, Not Genotype

2. Why Natural Selection Acts on Phenotype, Not Genotype

Evolution works through the mechanism of natural selection. This mechanism influences the genetic make-up of populations, acting on the population's physical traits. In this lesson, we'll explore examples of why this is.

Natural Selection & Adaptation: Definition, Theory & Examples

3. Natural Selection & Adaptation: Definition, Theory & Examples

How does natural selection help shape the amazing types of animals we witness around us? In this lesson, we'll explore adaptations and what they can tell us about a species' past evolution.

Speciation: Definition, Examples & Role in Evolution

4. Speciation: Definition, Examples & Role in Evolution

Can you believe that over two million species have been identified on Earth? Have you ever wondered how so many species formed on Earth? Learn more about how new species form and test your knowledge with a quiz.

Allopatric Speciation: Example & Definition

5. Allopatric Speciation: Example & Definition

If a continent splits, or a mountain range rises, one population can become two, and eventually the two populations may not be able to interbreed. Discover how species can split off from each other when they are separated.

Sympatric Speciation: Example & Definition

6. Sympatric Speciation: Example & Definition

How do species evolve from a common ancestor, even if they live in the same location? Sympatric speciation is an evolutionary process that drives this type of division between species that occupy the same habitat.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
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Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
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