Animals
Metazoa
This tree diagram shows the relationships between several groups of organisms.
The root of the current tree connects the organisms featured in this tree to their containing group and the rest of the Tree of Life. The basal branching point in the tree represents the ancestor of the other groups in the tree. This ancestor diversified over time into several descendent subgroups, which are represented as internal nodes and terminal taxa to the right.
You can click on the root to travel down the Tree of Life all the way to the root of all Life, and you can click on the names of descendent subgroups to travel up the Tree of Life all the way to individual species.
For more information on ToL tree formatting, please see Interpreting the Tree or Classification. To learn more about phylogenetic trees, please visit our Phylogenetic Biology pages.
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Information on the Internet
- Introduction to the Metazoa Animals, Animals, Animals!. University of California Museum of Paleontology.
- Animal Diversity Web. University of Michigan Museum of Zoology.
- BiologyBrowser: Invertebrata.
- The Shape of Life. Companion website to the PBS television series that reveals the dramatic rise of the animal kingdom through the breakthroughs of scientific discovery.
- The Origin of Animal Body Plans. 1997 American Scientist article by Douglas Erwin, James Valentine and David Jablonski.
- Animal Kingdom Gets a New Root. Wired Science, January 2009.
- New Tree Of Life Divides All Lower Metazoans From Higher Animals, Molecular Research Confirms. Science Daily, January 2009.
- The First Animal On Earth Was Significantly More Complex Than Previously Believed. Science Daily, April 2008.
- Tree Of Animal Life Has Branches Rearranged, By Evolutionary Biologists. Science Daily, March 2008.
- When we were worms. Report on research in early bilaterian evolution. BBC News.
- The Homeobox Page. Thomas R. Bürglin's page about the homeobox genes which play important roles in the development of multicellular organisms.
- A brief overview of Hox genes. Pharyngula.
- Marine Invertebrate Larvae: A Study in Morphological Diversity. University of Saskatchewan Archive of Dr. Thorston Lacalli.
- Introduction to Ichnology: The Study of Plant and Animal Traces. Emory University.
- The Wandtafeln of Rudolph Leuckart (1822-1898). Marine Biological Laboratory Woods Hole.
Metazoa in Special Habitats
- Marine Organisms at the MBL. Marine Biological Laboratory Woods Hole.
- Coral Reef Information System (CoRIS). National Oceanic and Atmospheric Administration, U.S. Department of Commerce.
- SeamountsOnline. NSF-funded project designed to gather information on species found in seamount habitats. San Diego Supercomputer and Scripps Institute of Oceanography.
- Voyage to the Deep. University of Delaware College of Marine Studies and Sea Grant College Program.
- International Association of Meiobenthologists (IAM).
- Anchialine Caves and Cave Fauna of the World. Thomas M. Iliffe, Texas A&M University at Galveston.
- Groundwater Biology Home Page. Giuseppe L. Pesce.
Fossil Metazoa
- The Dawn of Animal Life. Miller Museum Online Exhibit.
- Invertebrate Paleontology. Peabody Museum of Natural History, Yale University.
- Life of the Vendian. University of California Museum of Paleontology.
- The Burgess Shale : A Hidden Treasure In The Canadian Rockies. Hooper Virtual Paleontological Museum.
- Burgess Shale fossils. Andrew MacRae.
- Mazon Creek Fossils. Illinois State Museum.
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