Lab 3: Porifera and Cnidaria
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چکیده
AIMS: This lab will introduce you to the basal metazoan groups: the Porifera (sponges) and the diploblastic Cnidaria (hydroids, jellyfish, anemones, sea pens, corals, and relatives). You will see examples of the important fossil representatives of these groups: demosponges, hexactinellids, and archaeocyaths (Porifera); and the rugose, tabulate, and scleractinian corals (Cnidaria). The method of cladistics, by which we can best produce a hypothesis as to the evolutionary relationships among groups of organisms, is introduced. By the end of this lab you should be able to identify the major poriferan and cnidarian fossil groups, be familiar with the stratigraphic ranges of these taxa, and understand the basic operation of cladistic analyses.
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