Friday's class featured excerpts from 'Extinction!', which is Episode 3 from NOVA's 'Evolution' series (2001).
The video begins with paleontologist Peter Ward hunting for Permian fossils in South Africa's Karoo Desert, and relates ecological pyramids (which are like a 'house of cards') to mass extinctions, which are believed to be rare but important events in the history of life.
It then follows the work of American Museum of Natural History researcher Michael Novacek in building the fossil record of small, shrew-like mammals from the Mesozoic, representative of the lineage that will survive the next mass extinction (the K/T event), which will claim the dinosaurs.
It concludes with an examination of the role of human activity in accelerating the rate of extinction, with important attention to conservationists like Alan Rabinowitz. I encourage students to watch the video in its entirety for themselves if there are points that they don't get in class. We simply do not have enough class time to review this, but I know many students will want to see the whole story again, either by going to Google Video or watching it here: