My first experience teaching about animal bones took place on the subway in Boston. I was on the Red Line, somewhere between Chinatown where I attended classes as a first year Tufts veterinary student and my apartment in Somerville. I was carrying a conspicuous box: long, rectangular, wooden, with a handle on the top. There was no great way to carry it on the subway and especially on the Red Line where seats are placed lengthwise, along the walls of the car. When I was sitting, the box either extended into my neighbors’ laps, or it stuck out into the public walkway. As usual everyone was pretending not to notice everyone else, keeping their eyes lowered, but I knew people were stealing glances at the box. Finally one brave soul caught my eye and said, “So what’s in the box?” Everyone looked up. “Um, dog bones,” I said. No one looked away, so I clarified “They’re for vet school. I have to take home the bones to learn them.” But everyone was still looking, and the guy across from me gave a “You’re full of it” look, so I said, “You want to see?” Soon, we were passing around the dog tibia and scapula and actually having a group discussion. I was fielding questions including, “Is it true the dog has a bone in his penis? (“It is. Do you want to see it?”) “Is that femur from the dog’s back leg?” (“Yes.”) And, “Wait, they have the same bones that we do?” I realized two very important things during this impromptu commuter comparative anatomy class. One, despite how painfully shy I was, I enjoyed teaching. Two, most people don’t realize how much we have in common with other mammals.
This idea that we share most of our structure with other vertebrates is one that I find continually takes people off guard. People are surprised to learn that my veterinary school anatomy class met with the medical school class because the anatomy is essentially the same. They are surprised to learn that cats get diabetes and ferrets get the flu and dogs respond to Prozac. The fact that our bodies are more the same than different, and the way that these the variations evolved, are topics that fascinate me.
I eventually found my way into teaching in more formal settings than the Red Line. When this happened, I knew that I wanted to explore these similarities between animals and humans with my students. Teaching human biology at Wheelock, I ask my students to humor me and stand up and play Simon Says with me to learn the bones. “Put your hand on your femur. Wiggle your phalanges.” And so on. Then, I ask questions which I hope will get them thinking: “What kind of animal would you be if you didn’t have any arms or legs? What bones would be left? Why do humans and squirrels and cats have a clavicle but horses and giraffes don’t? What kind of teeth would you have if two of your incisors kept growing out of your mouth and rose up into the air?” These questions allow us to see our similarities, to understand how we are related to other animals, and to understand functions of particular parts.
My book, Bone by Bone: Comparing Animal Skeletons came out of this teaching idea (as did my upcoming book on teeth). The book has gotten a lot of press for teaching children about evolution. This surprised me at first because I wasn’t writing a book on evolution. The word isn’t even mentioned on the pages. But I do understand how people can see the book as setting a basis for children to understand evolutionary theory. When children learn how vertebrates that look very different on the outside have the same bones on the inside, they begin to understand how interrelated we are and how bones evolve to suit the functions each species needs. When they look at the illustration of the whale skeleton in the book, they may notice that while a whale doesn’t have back leg bones, it still has hip bones. With this sort of observation, inevitably good questions will arise. “How did it get this way? Why does this animal have a hip bone if it doesn’t have a leg (or back flipper) to go with it?”
I hope when this book is used in a classroom it will be a starting point in conversation, an introduction for children to make some connections and creatively explore new ideas. Here are some teaching ideas that have worked well for me when teaching children about skeletons. Teach them the names of bones in their bodies by playing Simon Says. Give them owl pellets to dissect and have them line up the bones they find on a drawing of a mouse skeleton to identify each one. If you can get access to a disassembled human skeleton, give each kid a bone and have them work together to build the skeleton on the floor. Or hand them each a mouse bone and have them find the analogous human bone. They will quickly understand that they are the same shape. Free teaching materials are available for download from the Lerner website that can be used with my book. Included are drawings of a human skeleton and those of various other animals to color in. By coloring analogous bones the same color, kids will clearly see the bones we have in common. Another good resource for realistic illustrations of animal bones that I often use is the book Skeletons: An Inside Look at Animals by Jinny Johnson.
My other hope for Bone by Bone is that kids will just enjoy the silliness of it. Learning should be creative and fun. If it leads them to begin to understand their own skeletal structure and how we are related to other animals, that’s a bonus.
The answers to the above questions, by the way, are as follows: if you didn’t have any arm or leg bones, the animal you’d be is a snake. Once the arm bones and the leg bones are removed and the bones that attach them—the hip bones and the shoulder blades—what remains are the skull, ribs and vertebrae, the only bones in a snake’s body. A clavicle is used for climbing. In order to climb, the arm bones need to be held apart with a rigid rod; the clavicle serves this purpose in humans and cats and squirrels and other animals that climb. If two of your top incisors kept growing out of your mouth and up into the air, you would have tusks, like an elephant. And, the reason the whale has vestigial hip bones is because it evolved from an ancestor that had back legs.
If you teach children and have questions or thoughts about how to use my book, please feel free to get in touch with me via my Wheelock email address. I’d love the opportunity to discuss ideas with you.
Dr. Sara Levine is a veterinarian, educator, and writer. Courses she teaches include Introduction to Plants and Animals, Animal Behavior, Human Biology, Natural History of New England, Human Disease, Science Writing, and Biology of Reproduction. She favors a hands-on and practical approach to learning. Her ongoing research with students at Wheelock is focused on the flora and fauna of the Muddy River. She practiced clinical medicine and performed surgery in small animal practice for five years. She has been teaching environmental education to children through the Massachusetts Audubon Society and other nature centers for over 15 years.
Levine is the author Bone by Bone: Comparing Animal Skeletons. Visit the book website.