Ch 21: Evolution Basics: Help and Review

About This Chapter

The Evolution Basics chapter of this High School Biology Help and Review course is the simplest way to master evolution. This chapter uses simple and fun videos that are about five minutes long, plus lesson quizzes and a chapter exam to ensure students learn about evolution basics.

Who's it for?

Anyone who needs help learning or mastering high school biology material will benefit from taking this course. There is no faster or easier way to learn biology. Among those who would benefit are:

  • Students who have fallen behind in understanding adaptation, selection and evolution
  • Students who struggle with learning disabilities or learning differences, including autism and ADHD
  • Students who prefer multiple ways of learning science (visual or auditory)
  • Students who have missed class time and need to catch up
  • Students who need an efficient way to learn about evolution
  • Students who struggle to understand their teachers
  • Students who attend schools without extra science learning resources

How it works:

  • Find videos in our course that cover what you need to learn or review.
  • Press play and watch the video lesson.
  • Refer to the video transcripts to reinforce your learning.
  • Test your understanding of each lesson with short quizzes.
  • Verify you're ready by completing the evolution chapter exam.

Why it works:

  • Study Efficiently: Skip what you know, review what you don't.
  • Retain What You Learn: Engaging animations and real-life examples make topics easy to grasp.
  • Be Ready on Test Day: Use the evolution chapter exam to be prepared.
  • Get Extra Support: Ask our subject-matter experts any evolution question. They're here to help!
  • Study With Flexibility: Watch videos on any web-ready device.

Students will review:

This chapter helps students review the concepts in an evolution unit of a standard high school biology course. Topics covered include:

  • Evidence, rates and theories of evolution
  • Genetic variability
  • Hardy Weinberg equilibrium equation
  • Natural and artificial selection
  • Speciation

20 Lessons in Chapter 21: Evolution Basics: Help and Review
Theory of Evolution

1. Theory of Evolution

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.

Evidence for Evolution: Paleontology, Biogeography, Embryology, Comparative Anatomy & Molecular Biology

2. Evidence for Evolution: Paleontology, Biogeography, Embryology, Comparative Anatomy & Molecular Biology

There is much support for the theory of evolution. This evidence comes from a variety of scientific fields and provides information that helps us trace changes in species over time. In this lesson, we'll look at this evidence and explore how it supports the theory of evolution.

Rates of Evolution: Punctuated Equilibrium & Molecular Clock Hypothesis

3. Rates of Evolution: Punctuated Equilibrium & Molecular Clock Hypothesis

In general, evolution is a very long process. But rates of evolution can be different for different organisms. In this video lesson, you will identify how scientists study rates of evolution and fill in some of the missing 'steps' in the fossil record.

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.

Natural Selection and Adaptation

7. Natural Selection and Adaptation

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.

Types of Natural Selection

8. Types of Natural Selection

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.

Speciation: Allopatric and Sympatric Speciation

9. Speciation: Allopatric and Sympatric Speciation

Discover the definition of a species and learn more about how species split. Find out common terms related to the splitting of species and study what role polyploidy plays in the development of a species.

Speciation: Prezygotic Barriers

10. Speciation: Prezygotic Barriers

We may take for granted why animals choose to mate with other animals of similar appearance, but it's not that simple. There are actually biological barriers to reproduction that can prevent even seemingly closely related species from reproducing. This lesson looks at one such category of hindrances, prezygotic barriers, which make fertilization impossible.

Speciation: Postzygotic Barriers

11. Speciation: Postzygotic Barriers

Do flying hamsters represent a separate species from your run-of-the-mill hamsters? We'll get to the bottom of this by performing crosses between the two hamster types. You'll explore postzygotic reproductive barriers and their possibly tragic consequences.

Genetic Variability and Random Mutation

12. Genetic Variability and Random Mutation

Evolution is driven by variation among populations. The amount of variability determines how well a population can adapt to environmental changes, while random mutations can provide new variations that help a population adapt to unexpected changes.

An Example of Rapid Adaptation: The Peppered Moths

13. An Example of Rapid Adaptation: The Peppered Moths

Normally, adaptations occur over thousands or millions of years. However, drastic changes in the environment can shorten the time period in which a change comes about. In such cases, we can learn a lot about the evolutionary process and how natural selection drives it forward.

Artificial Selection in Evolution

14. Artificial Selection in Evolution

Humans have been selectively breeding for desirable traits in plants and animals for a long time. This artificial selection allows for a lot of control in the breeding process but can also lead to unintended mutations within a population of organisms.

The Four Forces of Evolution

15. The Four Forces of Evolution

As you might have guessed, evolution in the natural world is not a simple proposition. There are four different forces that propel evolution onward. In this lesson, you will learn what those forces are and how they work.

Evolutionary Fitness: Definition & Explanation

16. 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.

Paul Ekman & Emotion: Face Training Study, Overview

17. Paul Ekman & Emotion: Face Training Study, Overview

You most likely can determine facial expressions depicting basic emotions such as a happy face versus a sad face. What is difficult to do is to read subtle facial expressions that to the untrained eye may appear neutral. Paul Ekman specializes in reading faces and was the inspiration behind the TV show Lie To Me.

Survival of The Fittest & Herbert Spencer: Definition & Examples

18. 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?

Evolutionary Relationships: Definition & Diagram

19. Evolutionary Relationships: Definition & Diagram

Just like you can build a family tree to show the relationships of your ancestors and their descendants, scientists can build trees to show the evolutionary relationships of species. In this lesson, learn how to interpret these evolutionary trees.

Vocal Tract: Anatomy & Diagram

20. Vocal Tract: Anatomy & Diagram

This lesson goes over the anatomy of the vocal tract, the amazing part of our body responsible for producing human speech. We will cover the larynx and the pharynx, the major components of our vocal tract.

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Other Chapters

Other chapters within the High School Biology: Help and Review course