It's been a while, but Old Bones is (hopefully) back. I'll be back with a new entry next week, but this week we have a guest blogger, Allison L. Beck. Allison completed her Ph.D. at the University of Chicago and was an undergraduate at Georgetown University. She has been a member of the Society of Vertebrate Paleontology for 15 years. Although her expertise lies in the limb skeletons of mammalian ancestors, Allison enjoys teaching courses on evolution, general zoology, human anatomy and comparative anatomy. Allison is currently a faculty member in the Biology Department at Augustana College in Rock Island, on the 'west coast' of Illinois. In her 'spare' time, Allison is a mom, a runner, and married to a biochemist.
It's spring break, in the winter, which must mean that I am preparing courses for the spring trimester. This spring, I'll be teaching a senior capstone course in my absolute favorite topics, under the umbrella of comparative anatomy and vertebrate evolution. I can't wait! Since we only have ten weeks, and the variety of courses the students have taken prior are heavily centered on genetics, and cellular and molecular-level biology, I have to start the term with a crash course in the methods and techniques by which we study vertebrate evolution. These students have never really done comparative anatomy, although they have all taken human anatomy, and they should at least know that a vertebrate is an animal with a backbone, among other special features (we'll leave the issue of hagfishes for some other time). Fortunately for me, there's a great book by one of our own that concisely and elegantly does the job for me, "Your Inner Fish: A Journey Into the 3.5-Billion-Year History of the Human Body", by Neil Shubin of the University of Chicago. The Shubin lab approaches the evolution of early tetrapods (four-legged vertebrates) from both a paleontological perspective and an evo-devo (evolutionary developmental biology) approach, and so does Your Inner Fish.
Leading the reader from an introduction to the patterns of vertebrate history evident in a simple walk through the zoo to a clear and simple description of Hox genes (genes responsible for the basic pattern of a body) and their role in producing body plans, Shubin hits on nearly every technique you might find presented at the annual meeting of the Society of Vertebrate Paleontology. He then discusses the history of our vertebrate senses; vision, smell and hearing (of course, one thing the reader discovers, and all paleontologists know, is that these are not all unique to vertebrates). Shubin finishes by tying it all together by discussing patterns of change in vertebrate bodies over deep time. Since the book is pitched to a fairly general audience, I was initially concerned that the science would be too simplistic for my fourth-year students. As anyone who teaches undergraduates knows, however, they tend to forget things, particularly when they don't use them regularly. When polled at the end of the term, the first students overwhelmingly gave Shubin's book a thumbs-up for speaking in a language they could understand. More importantly for me, it gave them a place to start deeper inquiry into the world of vertebrate evolution, a springboard of sorts for doing their own research into vertebrate history.
The results of this literature-based research are varied, since the students who take the class are as likely to be exceptional as they are average. We read scientific papers on vertebrate evolution together, have presentations and discussions, and finally the students present their own work. Ultimately, what I want is for my students to find out a little about the world I inhabit, to see that we are but modified tetrapods, with an unusual (in the animal world) capacity to puzzle together our own history and explain the incredible diversity on our planet. I hope that they continue to ask questions about our history and that of other vertebrates, and to marvel at how a few relatively simple processes, can produce body plans as divergent as a whale and a frog, or even a fruitfly (even though that is beyond the scope of my course). Without Your Inner Fish, my attempt to guide students through independent exploration of the technical scientific literature would not be nearly as fruitful, and not nearly as possible in a mere ten weeks. Indeed, anyone who is curious about how paleontologists find fossils, and how evolutionary biologists explain the origins of complex anatomic structures such as brains, fins and wings will find this book educational and enjoyable.