Article
Article
Invertebrate phylogeny
Article By:
Garey, James R. Department of Biology, University of South Florida, Tampa, Florida.
Last reviewed:January 2020
DOI:https://doi.org/10.1036/1097-8542.900222
The evolutionary or ancestral history of invertebrate organisms. The animal kingdom is composed of approximately 35 phyla, with each phylum representing a distinct body plan. Only a portion of one phylum (Chordata) includes vertebrates; the remaining organisms are invertebrate animals. Traditional phylogeny is based on a number of morphological and developmental traits, or characters. The animal kingdom is probably derived from unicellular protozoanlike ancestors, which most likely underwent evolutionary processes of cytoplasmic separation to form multiple cells. See also: Animal evolution; Animal kingdom; Phylogeny
The content above is only an excerpt.
About AccessScience
AccessScience provides the most accurate and trustworthy scientific information available.
Recognized as an award-winning gateway to scientific knowledge, AccessScience is an amazing online resource that contains high-quality reference material written specifically for students. Contributors include more than 10,000 highly qualified scientists and 46 Nobel Prize winners.
MORE THAN 8700 articles covering all major scientific disciplines and encompassing the McGraw-Hill Encyclopedia of Science & Technology and McGraw-Hill Yearbook of Science & Technology
115,000-PLUS definitions from the McGraw-Hill Dictionary of Scientific and Technical Terms
3000 biographies of notable scientific figures
MORE THAN 19,000 downloadable images and animations illustrating key topics
ENGAGING VIDEOS highlighting the life and work of award-winning scientists
SUGGESTIONS FOR FURTHER STUDY and additional readings to guide students to deeper understanding and research
LINKS TO CITABLE LITERATURE help students expand their knowledge using primary sources of information
