The Biology I Course was developed through the Ohio Department of Higher Education OER Innovation Grant. The course is part of the Ohio Transfer Assurance Guides and is also named OSC003. This work was completed and the course was posted in October 2019. For more information about credit transfer between Ohio colleges and universities, please visit: www.ohiohighered.org/transfer.Team LeadCathy Sistilli Eastern Gateway Community CollegeContent ContributorsLisa Aschemeier Northwest State Community CollegeShaun Blevins Rhodes State CollegeRachel Detraz Edison State Community College Sara Finch Sinclair Community CollegeWendy Gagliano Clark State Community College AJ Snow University of Akron Wayne CollegeLibrarianAmanda Rinehart Ohio State UniversityReview TeamJessica Hall Ohio Dominican UniversitySanhita Gupta Kent State UniversityErica Mersfelder Sinclair Community College
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.
By the end of this section, you will be able to do the following:
Explain the differences in animal body plans that support basic animal classification
Compare and contrast the embryonic development of protostomes and deuterostomes