Tuesday, March 24, 2009

How I Introduce Evolution to My Students at Tech

My training is in ecology, with a emphasis in the field of evolutionary ecology, so it is really not possible for me to talk about biology without using an evolutionary framework. As you might be remember, I started out this class by talking about “natural selection”- microevolution.

I have no idea what the exact figures are, but I know that the majority of my students come to Tech not-believing in evolution because of what they have learned from the pastors and parents while growing up.

When I teach evolution, I am simply trying to teach students the background theory that will help them make sense of the biological world. In the same way that I thought that understanding how scientists use mathematical models such as the Lotka-volterra model of competition to understand communities, I think that it is imperative that students studying biology have a strong foundation in evolutionary theory. Thus, I am not trying to “convert” anyone or to challenge their religious beliefs. I do however find it interesting that I am more likely to challenge people’s religious beliefs when talking about evolution than I am when talking about competition models. We should spend some time talking about why that is.

I always start by talking about science. Science is a way of learning about the world. Other ways of learning about the world include philosophy and religion.

Science is differentiated from alternative ways of learning about the world by
1) what it studies
2) how it studies it

(a) Science deals with the natural world and assumes that the world is governed by “natural laws” (I don’t spend too much time worrying about where these laws came from, I just accept that they exist)and (b) science only studies things that can be observed

Religion, on the other hane deals with the supernatural so science simply can’t study it.

Scientists learn about the world using the scientific method. Scientists use observations and experiments to test predictions of hypotheses. Thus, data determines “truth” in science. Religious truth often relies on “revelations” not data.

Thus, science and religion differ on what they can study and how they study it.
Here is the critical question- which way of learning about the world is best? Any particular method is not the best, they are complementary ways of learning about the world and each works best within its intended boundaries. Science has nothing to say about religion, faith, or God.

My suggestion is that if you want to study observable phenomena that take place in the natural world then science is the best approach. We spend our lives surrounded by the applied knowledge that comes from using the process of science.

Think about a couple of examples

1) you come out in the morning and you can’t start your car.

Possible hypotheses
- you left your lights on and the battery has gone dead
- something is wrong with the starter

Where do these hypotheses come from? The knowledge that engines run according the laws of physics and chemistry helps us to understand how they work

Alternative hypotheses
-you ran over a fairy on the way home last night and they are punishing you
-your neighbor is a witch and has put a hex on your car because your dog barks too much

We are likely to laugh at these alternative hypotheses because we understand the mechanical basis of car problems. Who do you take your car to for repairs- (i) Gus the mechanic (who whether he knows it or not uses his knowledge of physics and chemistry to diagnose what is wrong and repair your car) or (ii) Princess Fatima the Gypsy around the corner? Obviously, we choose Gus.

2) What do you do if you get sick?

The most obvious answer is that you go to the Doctor and do what they tell you. Certainly you might ask people to pray for you or pray for yourself. Some religions (e.g., Christian Scientists) rely on spiritual healing alone and will not take their children to the doctor when they are sick. I doubt that most people around here would support that position.

Here is a great quote from Einstein- “The whole of science is nothing more than a refinement of everyday thinking.”

In my introductory Biology class I discuss the evolution of plants. Never have I had a student have problems with green algae giving rise to mosses, mosses evolving into ferns etc. The problem arises when we start talking about human origins. Humans descended from apes- monkeys are ancestors.

Why this is is difficult for me to understand- it appears that we are in the middle of a culture war. From an exhibit in the Institute of Creation Research Museum we learn that (i) Creationism gives us True Faith, True Morality, True Hope, True Americanism, True Family Life and (ii) Evolutionism gives us Communism, Naziism, Atheism, Slavery, Racism, Pornography, Genocide, Abortion, Infanticide , Homosexuality, Child Abuse, Bestiality. This goes back to William Jennings Bryan’s ideas of evolution causing a loss of morals. I don't understand this point of view, but clearly this is the way that many people think which is why they are willing to fight so hard to get creation in and evolution out.

I think that students should be encouraged to think about how they use the different ways of learning about the world. When do they use science, when do they use religion? What do they do when the two are in conflict? How do they justify using science to study the world expect for when it conflicts with their religious beliefs (why doesn’t science work then?). Each person needs to draw their own conclusion about these issues. However, I think that it is extremely important that we not allow people to push their “religious agendas” into the science classroom.


  1. I find my 8th graders are very curious about evolution but I don't really have it in my curriculum. However I just finished an activity called Evolution by Natural Selection and none of my students were freaked out by it. Of course it was about populations evolving over time so not as close to home as humans and apes evolving from a common ancestor. I have had a couple of run ins with students and parents over some of the topics taught in the last few years though.

  2. I also do not have anything in my objectives that address evolution. In my previous district a few parents were concerned of this topic though. Ironically I taught 5th grade science and it was never addressed in these TEKS either. We talked a bit on this topic in our summer courses. The key is to teach objectively and leave your personal beliefs out of the classroom I guess. I have been lucky that I have never had to address this with my students and parents I guess. When does this topic show up...HS Biology?