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Unformatted text preview: The ancestor probably resembles modern choenoflagellates? Paleozoic Era Cambrian explosion, created new ecological inches, unique because there was not an immediate extinction happening before. Scientists came up with some hypotheses: 1. New predator-prey relationships developing. 2. O2 increases dramatically. Homologous Hox genes establish body plans in animals that have not shared a common ancestor in hundreds of millions of years. In addition, major evolutionary changes may be based on Hox genes. Grade Porifera:- Sponges called Porifera imply a monophyletic clade, but this is NOT TRUE. They are much more complex than this. (Pore carriers, meaning they have lots of pores), Adults: sessil, filter feeders Larvae- motile Vast majority have no symmetry, no true tissues, and are mostly marine. Bernaullis Principle (has a net-like feeding structure. ) 1. 2....
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This note was uploaded on 03/19/2012 for the course BISC 1112 taught by Professor Doebel during the Spring '12 term at GWU.
- Spring '12