I used to teach ninth graders biology. Many years ago during those pre-school parent-teacher meet and greets, I was speaking to a father and son when my future student piped up with a question.
Student: “Will we be learning about evolution?!”
He said this with a sort of excited enthusiasm that left me regretting that I would have to report that we would never touch on it directly. Not wanting to disappoint the child too much, I at least tried to sugarcoat the news.
Me: “Not directly, but we do cover a good bit about genetics and some of the various types of creatures that have evolved, which is all pretty important to evolution. Why? Are you interested in it?”
Father: “Yeah, I’d say he definitely is.”
The father said this with a sort of half-exasperated, half-proud, joking tone that suggested that he may have heard more about evolution from his son than he really wanted to know but was still proud of his son’s enthusiastic learning.
Still, I am a scientist — or at least, I spent my life teaching others how to be scientists — so I don’t like to presume something I could test.
Me: “Well, let’s see what you know. Can you explain what ‘survival of the fittest’ means?”
Student: “It means that over generations, the less fit animals will die out and leave only the more fit, better-adapted ones to reproduce.”
Me: “But what makes an animal fit?”
Student: “Being better able to pass on their genes. Usually, that means surviving long enough to have children that will also survive to reproduce.”
Me: “Usually?”
Student: “There are other ways to pass on genes like helping closely related family members to have children, but having kids of your own is usually the main strategy.”
Me: “That’s a wonderful answer. To be honest, I just wanted to see if you would say being fit meant you had to be stronger and faster like most people think, but you gave a much better answer. Good job.”
Student: “Oh, no. I know better than that. I’ve read enough that I might even know some things you didn’t know!”
At the start of this exchange, he sounded almost disappointed that I had asked such a simple question of him, but as I asked my follow-up questions, he sounded increasingly excited to answer them.
Me: “Okay, I’ll take you up on that. Tell you what: if you can teach me something new in the next five minutes, I’ll give you an extra credit point when you start this year.”
Student: “Really?! Okay, umm, you probably know about the Fisher principal and Red Queen hypothesis stuff, right? What about koinophilia?
Me: “Sorry, know all that.”
Student: “Ring species? Island gigantism?”
Me: “Don’t think I know that last one. Can you teach it in the next four minutes?”
Student: “When herbivores manage to migrate to a small island, they usually evolve to be bigger if they used to be small, or bigger herbivores would evolve to be smaller if you want an example of when being fit meant being weaker and slower. It’s because small islands can’t support a breeding population of predators; they would all starve. So, without predators, the herbivores don’t need adaptations to defend against them. Being really small or large is usually a defense against predators, to be able to either hide from them or be too tough to be hunted. Without predators, herbivores will lose those and other defensive adaptations they no longer need so they can focus their energy more on producing children instead. That’s why the dodo bird was so big and like it was. It wasn’t stupid, but being big, unable to fly, and not knowing to run from potential predators like humans all makes sense if you evolved on an island without predators to flee from.”
After he explained it, I got a strong feeling I had learned that before, but since I clearly didn’t remember the idea perfectly, and I’m almost certain I had never thought to apply it to dodos, I figured it counted as teaching me something and gave him his extra credit point.
That was the start of a year-long pattern of his catching me after class to teach me whatever cool thing he had recently learned about evolution. I ended up giving him the chance to earn a single extra credit point each semester if he could first correctly answer a “trick” question of mine about evolution and then come up with a new thing to teach me about evolution or a closely related topic. The point was too small to have any real effect on his grades, which didn’t need the extra credit anyway, but he still seemed to love having a chance to earn his one measly point each semester.
I know it seems silly, but his enthusiasm for the subject has always made me smile, even all these years later. You rarely get someone so dedicated to learning a subject you’re there to teach, and it’s those occasions that really give meaning to us teachers.
