Ch 23: Introduction to Vertebrates

About This Chapter

Watch video lessons and learn how animals with backbones and spines evolved over time. These easy-to-follow lessons are just a portion of our online study guide and video collection.

Introduction to Vertebrates - Chapter Summary and Learning Objectives

The videos in this chapter are designed to help you understand the unique characteristics of vertebrates, one of the two main groups of animals. The chapter opens with a discussion of chordates, an animal phylum composed of both invertebrates and vertebrates, including us! Although vertebrates are a diverse group, you'll also find out what types of characteristics animals with a backbone have in common.

In particular, the chapter will provide you with information about jawless vertebrates, such as certain kinds of fish, and amphibians. You'll also find out about amniotes or 4-legged animals. When you've finished watching the videos, you should be able to:

  • Identify the common characteristics of vertebrate animals
  • Identify the unique characteristics of specific vertebrates, including amniotes and primates
  • Understand the evolutionary relationship and origins of invertebrates and vertebrates
  • Understand how the unique features of primates can aid in the discussion of human origins

The Origin of Vertebrates and Invertebrate ChordatesDefine the characteristics of the two major subphyla of chordates without a backbone. Describe how invertebrate chordates provide clues to the origin of vertebrate animals.
Vertebrates: Characteristics and DiversityDiscuss some of the characteristics of vertebrates, including their diversity.
Jawless Vertebrates: Class Myxini and Class CephalopodaDescribe the distinct features of jawless vertebrates, including class myxini and class cephalopoda.
Amphibians and Fishes: The Origins of Jaws in VertebratesExplain how vertebrate jaws evolved from skeletal supports of the pharyngeal slits. Identify and highlight the characteristics of the following classes: chondrichthyes, osteichthyes, tetrapods and amphibian.
Amniotes: Definition and Evolutionary CharacteristicsDefine amniotes and their characteristics, as well as how they can help to explain the evolution of vertebrate animals.
Primates and Human OriginDiscuss the unique features of primates. Consider how these properties can provide a context for human origins.

6 Lessons in Chapter 23: Introduction to Vertebrates
Test your knowledge with a 30-question chapter practice test
Vertebrates: Origin, Characteristics & Diversity

1. Vertebrates: Origin, Characteristics & Diversity

Vertebrates are diverse and widespread across Earth, but this was not always the case. In this lesson you'll learn about the origins and evolution of these animals, as well as explore their vast diversity.

Jawless Craniates: Class Myxini & Class Petromyzontida

2. Jawless Craniates: Class Myxini & Class Petromyzontida

The word 'fish' brings specific images to mind. But before these fish existed, there were the jawless craniates. In this lesson you will identify two classes that fall into this category: the hagfishes and the lampreys.

Fishes and Sharks: Origins of Jaws in Vertebrates

3. Fishes and Sharks: Origins of Jaws in Vertebrates

While it may appear to be a minor feature, the hinged jaw led to major changes in the evolution of animals. In this lesson, you'll discover some of the earliest jawed animals, the sharks and fishes of the world.

Tetrapods: Development of Limbs in Vertebrates

4. Tetrapods: Development of Limbs in Vertebrates

Having four limbs allowed for an incredible amount of diversification in the animal kingdom. But where did those limbs come from, and what types of diversifications arose from animals moving onto land?

Amniotes: Definition and Evolutionary Characteristics

5. Amniotes: Definition and Evolutionary Characteristics

One of the more 'recent' evolutionary developments in vertebrates is a terrestrial egg. This adaptation allowed for even greater diversity in this branch of the Animal Kingdom, giving rise to organisms that could now live their entire lives on land.

Primates and Human Origin

6. Primates and Human Origin

You probably know that you are a primate, just like gorillas and monkeys. But you may be surprised to find out how long primates have been around and how many of them are still living on Earth, which are covered in this lesson.

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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