Ch 8: Biology: Evolution & Natural Selection

About This Chapter

This chapter covers a diverse array of topics related to the studies of evolution and natural selection, lending you a rounded understanding of the subject through lessons on genetic drift, social Darwinism, population bottleneck, and more.

Biology: Evolution & Natural Selection - Chapter Summary

This chapter provides a comprehensive review of evolution and natural selection, discussing relevant terms, theories, and the figures at the helm of them. Topics include the founder effect, types of natural selection, evolutionary fitness, and all of the following:

  • The theory of evolution and the characteristics and history of human evolution
  • Dispersion, migration, and carrying capacity
  • Hardy Weinberg equilibriums I, II, and III
  • Herbert Spencer and survival of the fittest
  • Evolutionary change

With the option of reviewing the material through a video or transcript of each lesson, you'll be able to learn in the manner that best suits your style. The practice quizzes attached to every lesson allow you a handy way of checking your comprehension topic-by-topic, while the practice final exam gives you the chance to test yourself on a more overall level.

14 Lessons in Chapter 8: Biology: Evolution & Natural Selection
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.

The Evolution of Humans: Characteristics & Evolutionary History

2. The Evolution of Humans: Characteristics & Evolutionary History

Just like other organisms, humans have changed over time. We will look at the evolution of humans as well as connections with our primate relatives, including Old World and New World primates.

Carrying Capacity, Migration & Dispersion

3. Carrying Capacity, Migration & Dispersion

Have you ever wondered why some types of birds fly south in the winter or why some animals form territories? Watch this video to learn about a species' maximum growth capabilities, the way its members group themselves and why they might migrate to new locations every year.

Hardy-Weinberg Equilibrium I: Overview

4. Hardy-Weinberg Equilibrium I: Overview

In this lesson, we'll examine population genetics in greater detail. We'll also explore notions of Hardy-Weinberg equilibrium for large, stable populations. Is the genetic makeup of our flying hamster population changing? The Hardy-Weinberg equilibrium can serve as a reference point as we try to answer population genetics questions.

Hardy-Weinberg Equilibrium II: The Equation

5. Hardy-Weinberg Equilibrium II: The Equation

The Hardy-Weinberg equilibrium equation is represented by a polynomial, so we'll have to do some calculations. Don't be intimidated; a few coin tosses can help us make sense of allelic frequencies in a given gene pool.

Hardy-Weinberg Equilibrium III: Evolutionary Agents

6. Hardy-Weinberg Equilibrium III: Evolutionary Agents

In this lesson, you'll learn how the Hardy-Weinberg equation relates to different evolutionary agents and population changes. Discover how the equation may be used to discover populations that are not in equilibrium.

Genetic Drift: Definition, Examples & Types

7. Genetic Drift: Definition, Examples & Types

Genetic drift reduces genetic variability of a population by decreasing the size of the population. The change in population size and variability often leads to new species and unique populations.

Population Bottleneck: Definition & Explanation

8. Population Bottleneck: Definition & Explanation

Once upon a time, the earth was full of cheetahs - but then, thousands of years ago, most of them died off. (Zombie cheetah apocalypse? We don't know.) Discover what a population bottleneck is and what it means for the cheetahs that are left.

Founder Effect: Example & Definition

9. Founder Effect: Example & Definition

The founder effect is one way that nature can randomly create new species from existing populations. In this lesson, learn about the founder effect and how it can be seen in all humans across the globe.

Natural Selection: Definition, Types & Examples

10. Natural Selection: Definition, Types & Examples

We'll take a look at the types of natural selection that can occur. From flying hamsters to moths, you'll start to grasp the different paths organisms can take as they respond to their changing environments over time.

Survival of The Fittest & Herbert Spencer: Definition & Examples

11. Survival of The Fittest & Herbert Spencer: Definition & Examples

What is Social Darwinism? How is it different than evolution? What does Social Darwinism have in common with Darwin's theories of evolution? Where did Survival of the Fittest come from, and what does it mean?

Social Darwinism: Definition & Meaning

12. Social Darwinism: Definition & Meaning

Social Darwinism got its name due to the similar foundation it has to Charles Darwin's concepts of natural selection and the survival of the fittest. Darwin used these concepts to explain evolution. Learn about how these concepts are applied socially.

Evolutionary Fitness: Definition & Explanation

13. Evolutionary Fitness: Definition & Explanation

Why is 'Survival of the Fittest' wrong? What did Darwin actually say? Does your brain have anything that makes you a better hunter? This lesson will discuss evolutionary fitness, natural selection and how they might relate to the evolution of the human mind.

Evolutionary Change: Definition and Forms

14. Evolutionary Change: Definition and Forms

You've probably heard of Charles Darwin and evolution. We know that evolution is change over time, but here we will look at how these changes may have occurred during Earth's history.

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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