Ch 21: Evolution, Natural Selection & Biological Diversity

About This Chapter

You can learn about evolution, natural selection and biological diversity with the help of the lessons in this chapter. When you complete the lessons, there are self-assessment quizzes that will measure your level of comprehension.

Evolution, Natural Selection & Biological Diversity- Chapter Summary

You can use these entertaining and concise lessons to learn about important science topics such as evolution. Our professional and knowledgeable instructors designed these lessons in ways that are easy to understand. Topics you'll study in the lessons for this chapter include:

  • Evolution theory and how populations and traits evolve
  • Influences of natural selection on the environment
  • How new species form through speciation
  • Evidence of evolution
  • Information that fossil records give on evolution

These lessons are mobile friendly. They can be accessed via a tablet or smartphone as you master the material. Having the freedom and flexibility to access these lessons wherever possible maximizes the study experience. In addition, these lessons can be reviewed multiple times until you have a handle on the information.

5 Lessons in Chapter 21: Evolution, Natural Selection & Biological Diversity
Test your knowledge with a 30-question chapter practice test
Theories of Evolution: Lamarck vs. Darwin

1. Theories of Evolution: Lamarck vs. Darwin

We'll look at the interplay between population genetics and environment. Are traits individually acquired or do entire populations evolve? The flying hamsters and a few other notable experiments will provide the answers.

Natural Selection & Adaptation Processes

2. Natural Selection & Adaptation Processes

Through the process of adaptation, natural selection shapes the variety of life that exists around us. This lesson will explore some of the ways this process can take place.

Overview of Speciation Types & Barriers

3. Overview of Speciation Types & Barriers

Have you ever wondered how a new species arises? This lesson will examine speciation, or when a new species forms, as well as barriers that prevent separate species from mating.

Scientific Evidence That Supports Evolution

4. Scientific Evidence That Supports Evolution

Evolution explains how species that are present on Earth today are modified descendants of their ancestors. This scientific theory is supported by many different types of evidence, which show how evolution is a very real and natural phenomenon.

Fossil Evidence for Biological Diversity, Speciation, & Mass Extinction

5. Fossil Evidence for Biological Diversity, Speciation, & Mass Extinction

One of the best sources of evidence we have for evolution is the fossil record. Fossils provide a wealth of information on how species change over time and for exciting events like mass extinctions and new species formation.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

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