The winter term is off and running and I started teaching yesterday. I teach my first-year course in Evolution and Phylogeny every winter. And I love teaching this course. By the end of most of my lectures, when my throat is dry and when I have chalk dust all over everything, I gather up my notes and realize I’ve had a great time for the past 90 minutes. Why? Because I’ve been telling a story. And because I think the story of the history of life on earth is the best story there is.
Four billion years of never-ending plot lines. Four billion years of character development. Four billion years of unexpected twists and turns — the Cambrian explosion! life on land! endosymbiosis! the asteroid that ended the Cretaceous! the rise of diversity in Hawaii or the Galápagos! Brilliant stuff.
I get the chance to tell stories about amazingly elegant mechanisms that drive evolution. The way DNA copies itself and builds new life, the great lottery of mutation and selection, the birth and death of species, the growth and pruning of branches on the tree of life. And once the students understand the processes that build the great tree of life, they learn methods to reconstruct and read that tree, and then to hang hypotheses and predictions on the framework that the tree provides to the rest of biology.
And it’s not just the processes and the patterns themselves that make great stories. Science is ultimately a human endeavor, so the history and development of evolutionary thought carries the baggage of human nature. The history of evolution is a story of philosophers trying to understand the world, a story of cultural institutions trying to maintain their hold on authority. It’s the story of poor old Lamarck being in the wrong place at the wrong time and coming up with an idea just a little too flawed and a half-century too early. It’s the story of Darwin and Wallace being in the right place at the right time to see a few key facts, and read a few key books, and to come up with a brilliantly simple yet powerful idea at exactly the same time. It’s the story of a group of geneticists and paleontologists and statisticians and botanists and ecologists coming together and filling in the missing pieces of the puzzle that Darwin and Wallace couldn’t solve in their lives. It’s a story of modern anti-scientists trying to force their own agendas on teachers and schoolchildren in the guise of “science”.
I spend four months every winter telling these stories to a hundred new students each year. Stories about stalk-eyed flies fighting on a log in the rainforest, and mutant plants that adapt to toxins dripping from a galvanized wire fence on the prairie, and parthenogenetic fish that live in the space between two “normal” species, and flowers or frogs that survive just fine with too many chromosomes, and one or two flies or birds or plants that were blown to a new and empty island and exploded into their own tree of life in that brand new world.
And I never get tired of it.
How can you get tired of telling the greatest story on earth?