Animal Diversity—Part II Introduction Last lab you were introduced to animals and provided with some ways to think about them (body plan, phylogenies and trait mapping, adaptations for feeding/respiration/locomotion, etc…). This week we will look in detail at more of the major animal phyla. You goal is to recognize these groups, understand their evolutionary relationships, and learn their key morphological features. You will not see these animals in lecture until next week. This lab is meant to introduce you to some major themes on the structure and function of animals using some organisms you may already be familiar with. You will understand the lab better if you read Chs. 33 and 34 before you come to lab. Lab Organization Today’s lab is laid out as a series of stations that introduce you to some common themes in the evolution and morphology of protostome and deuterostome animals. Visit each station and use the material at that location to help you understand what you have read in Chs. 33 and 34. Body Plans One fundamental way that animals can be categorized is by reference to their body plan, the basic features of its structural and functional design. In addition to these, animal phyla are often characterized by synapomorphies added to an ancestral the body plan. In today’s lab you will see some of the features that define the major phyla of animals and understand their importance for body architecture. Functional Morphology Remember that some key challenges for all animals include respiration, feeding, locomotion/attachment, and reproduction. As you view the stations today be sure you understand the function and importance of the new morphological features you will view. Important themes will include life cycles within the parasitic groups, the transition from juvenile to adult, and the types of body support (‘skeletons’) scattered through the phyla. You will may be surprised by some of the ways organisms deal with these fundamental challenges. Evolutionary Relationships Because all animals are descended from a common ancestor, it is useful to organize the diversity of animal groups using a phylogeny. Use the phylogeny of major animal groups attached (Fig. 32.10). For some phyla you will see phylogenetic trees that zoom in on differences among subphyla or classes. These will illustrate important concepts, such as evolutionary radiation, the relationship of symmetry and cephalization, or other trends in animal evolution. Derived metazoan phyla This week we will concentrate on a subset of phyla that illustrate key innovations in the Animalia. We will look at three major clades within animals: • the lophotrochozoa (Phyla Mollusca and Annelida), • the ecdysozoa (Phyla Nematoda and Arthropoda), and • the deuterostomes (Phyla Echinodermata and Chordata). This week’s stations will cover each of these groups in detail, highlighting selected key features. Lab Write Up Your lab write up should include notes on the information at each station, as well as your answers to any questions found in the station notes. You should also include relevant sketches or diagrams to help you learn and remember the key concepts of today’s lab. Finally, you should complete the summary table of animal features you started in last weeks lab. You may have more information on this week’s derived animal phyla. Your completed table can be used as a study aid for both lecture and lab, so keep it with.