In this unit, we will be investigating the major groups of vertebrates. We will be using a cladistic approach as we study them, following the evolutionary tree along each branching point. The unit lessons are organized by character states. In each lesson, we will look at the structure (or structures) that distinguish the group and the animals, both extinct and extant, that are included. This unit is where we will begin our virtual dissections. Our dissections will include: *** In addition, where possible, we will also be examining representative species in other ways using models and preserved specimens. (This unit will conclude with a field trip and project at the American Museum of Natural History if Covid-19 conditions allow.)

1. Vertebral Column & Brain Case (Vertebrates)

2. Jaws (Gnathostomes)

3. Limbs (Tetrapods)

4. Watertight Egg (Amniotes)

5. Skull Openings (Sauropsids & Synapsids)

6. Middle Ear Bones (Mammals)

7. Placenta (Placentals)

8. Stirrup-shaped Stapes (Epitheres)

9. Hoof (Ungulates)