Introduction to Animal Diversity Resources
Animal evolution began in the ocean over 600 million years ago with tiny creatures that probably do not resemble any living organism today. Since then, animals have evolved into a highly diverse kingdom. But what is an animal? While we can easily identify dogs, birds, fish, spiders, and worms as animals, other organisms, such as corals and sponges, are not as easy to classify. Animals vary in complexity—from sea sponges to crickets to chimpanzees—and scientists are faced with the difficult task of classifying them within a unified system. They must identify traits that are common to all animals as well as traits that can be used to distinguish among related groups of animals. The animal classification system characterizes animals based on their anatomy, morphology, evolutionary history, features of embryological development, and genetic makeup. This classification scheme is constantly developing as new information about species arises. Understanding and classifying the great variety of living species help us better understand how to conserve the diversity of life on earth.
List the features that distinguish the kingdom Animalia from other kingdoms.
Describe the various ways animals reproduce.
Describe the steps of embryonic development.
Describe the roles that Hox genes play in development.
Describe the three types of symmetry and name a group of animals that has that type.
Describe the differences between the Parazoa and Eumetazoa.
Describe the differences between acoelomates, pseudocoelomates, and eucoelomates.
Discuss the differences in the embryonic development of protostomes and deuterostomes.
List the major clades of animals and describe the major relationships between them.
Name the types of data that scientists use to construct and revise animal phylogeny.
Discuss some of the relationships within the modern phylogenetic tree that have been discovered as a result of modern molecular data.
Describe the features that characterized the earliest animals and approximately when they appeared on earth.
Explain the significance of the Cambrian Explosion for animal evolution and the possible causes.
Name two major mass extinctions and describe their effects on animal diversity.
Identify major radiations that occurred during the Cenozoic Era.
Recommended Textbook Resources
Chapter 27: Introduction to Animal Diversity
OpenStax: Biology 2e
A review of the characteristics shared by all animals, including embryological development, and the characteristics used to classify different animal groups. The later are used to explore major animal phylogenetic relationships. Also included in a brief overview of the evolution of animals from Precambrian life through the Cenozoic.
Student Assessment Activities
Go to https://evolution.berkeley.edu/evolibrary/news/120501_habitatloss and read the article entitled “Lessons for today in ancient mass extinctions”. Answer the six Discussion and Extension questions at the bottom of the page and submit your answers to your instructor.
Go to https://evolution.berkeley.edu/evolibrary/news/120901_afterextinction and read the article entitled “What comes after mass extinctions?” Answer the seven Discussion and Extension questions at the bottom of the page and submit your answers to your instructor.
Instructors should go to https://evolution.berkeley.edu/evolibrary/teach/Phylogenetics_Lab_Catley_Novick.pdf to find the student handout and instructor handout for the lab “Phylogenetics Laboratory: Reconstructing Evolutionary History”. The lab is written for students to complete in class while viewing preserved specimens of major animal phyla along with a computer or textbook to look up different traits of each group, but the lab could be adapted to an online setting by providing images of the specimens/samples. Students submit the lab for grading.
Find the correct answers to the end of the chapter “Review Questions.” Note the page number on which you found the answer. Be prepared to share and explain your answers in a group setting.
Answer the end of the chapter “Critical Thinking Questions.” Note the page number on which you found the answer. Be prepared to share and explain your answers in a group setting.