I finished my final class for the year in Evolution & Phylogeny the other day. The students wrote their final exam yesterday. By today I figure some of the course content has already hit its half-life and it’s on its way to being overwritten by other things in their minds. I’m ok with that; I’m a realist. In that room of 104 faces, am I really so naïve/disconnected to think they’ll all become evolutionary biologists? (the answer is no, by the way). It’s a required first-year course for our Environmental Biology and Life Science majors, and the students are headed off in many directions. Some who have sat through that course are professional evolutionary biologists or taxonomists today. Most are doing other things and my great hope is that those things make them happy.
Several years ago I thought about all this, and started making a list of the things I hoped the students would take away from the course and retain after their undergrad degrees were over. And every year since then, I’ve wrapped up the last session of Evolution class with a list of six things I’d like them to remember five years later if we run into each other somewhere out in the world. Here’s the list of Five-Year Memory:
The Wisdom of Theodosius Dobzhansky
in 1973, Dobzhansky published an essay in American Biology Teacher called “Nothing in biology makes sense except in the light of evolution.” I use that quote to start the first class in the course, and it runs as a theme through the term. Because life on earth is all interconnected through time, and because most things about organisms — their genetics, morphology, physiology, behavior, distribution, ecology — evolve, an understanding of evolution becomes a powerful context for understanding similarities and differences across the living world, regardless of your interest in biology.
The Power of a Tree
A phylogenetic tree is a picture of history. If our hypothesis of the relationships of a group of species is a good one, we’ve got a framework for understanding known things about species, and making reasoned predictions about the things we don’t know. I don’t expect all the students to remember how we went from characters to matrix to trees in the lab, or the speciation processes that grew those trees in the first place. But I’d like it if, when they see phylogenetic trees in papers or the media, it triggers something about the vast and varied amount of information contained in those twigs and branches.
Change is Constant
The evolutionary processes we talked about in the course grew out of the interplay between mutations and selection and organisms and environment. And those things are almost always happening. The world in which organisms live is always changing, sometimes a little, sometimes a lot, and those organisms are changed along with it. Life evolves; the way we do science evolves; the way we communicate and share science evolves. Prepare to adapt. Prepare for change. It’ll be along shortly.
After hundreds of years of accepting “conventional wisdom” in the form of ancient writings, western Europe woke up in the Renaissance because a bunch of people started asking “Why?” And those people became the philosophers and astronomers and anatomists and physiologists and chemists and artists who changed the way we do science and understand the world. The first step in finding an answer is to ask “why?”
Some of the best ideas and innovations in science today come from students and postdocs who don’t simply accept what’s written in the papers or pronounced by professors. They play around with “conventional wisdom” to see if it holds up. That’s how science keeps moving forward. Always ask “why?”
It’s a weird paradox that a lot of biology is taught inside rooms without windows. We wander off on tangents all through the term about how amazing and varied the living world is, and how the things growing and living and dying out there are the product of all these processes we talk about in the course. But take the opportunity to go outside into the world and experience all those things for yourself. You don’t have to go far! Life is going on all around, in cities, in back yards. Go have a look. Explore it. Poke nature.
Depending on the combination of courses they take in their undergrad program, the students in that class will, by the end of their degree, be able to go outside, look up at a bird flying by, and deconstruct it into a branch on a phylogenetic tree, a legacy of the dinosaurs, a set of categories in a classification, a suite of behaviors, a node in a food web, a series of biochemical pathways, a biomechanical marvel of engineering, and an aerodynamic equation that explains how those wings keep it airborne. That’s all great, and that’s all science, and that’s all valuable. But what’s equally valuable is the ability to go outside, temporarily forget all of that information, look up at the bird and think “That. Thing. Can. FLY”. Because we all need some magic.
I was at a conference a couple of years ago and ran into a student who’d taken my course a few years earlier. He was doing a PhD in ecology in the US by then. We said hi. Good to see you. The usual. Then, out of the blue, he said “Hey! I remember the five-year list!”
In a career in science, dotted with the odd award here and there, conversations like that one are the prizes I can retire on.