Abstract
During the course of metazoan evolution there was a tendency for a reduction in the external body surface area so that of exchange surfaces were localized within the protected interior of the body. The Cnidaria stand at the beginning of the evolution of the Eumetazoa and show, in several respects, certain unique features, e.g. the reduction in external surface area has not yet taken place; on the contrary, there is an increase in the outer body surface. Arguments for the evolutionary success of the laminate body organization of cnidarians are, in part, the subject matter of this chapter.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
