Newsflash: American science teachers are so afraid of controversy, so intimidated by students and parents who dispute the theory of evolution, that, according to this recent survey, more than half do not even take a stand on the issue with their students. And one in eight actually promote creationism. Only about 28% consistently teach evolution.

And from Tennessee comes the news that conservative lawmakers there are working on a law that will require science educators there to "teach the controversies" regarding evolution and climate change.

An article in Mother Jones describes the bill:



"The teaching of some scientific subjects, including, but not limited to, biological evolution, the chemical origins of life, global warming, and human cloning, can cause controversy," the bill states. Further, the state will not prohibit any teacher from "helping students understand, analyze, critique, and review in an objective manner the scientific strengths and scientific weaknesses of existing scientific theories covered in the course being taught."

Update, Jan. 14, 2012: Republican legislators in Missouri have introduced a bill that will require K-12 teachers and introductory science courses at the college level as well to teach evolution. Meanwhile, over at the Washington Post, Jay Mathews has authored a rather unlikely post suggesting Rick Santorum should stay in the presidential race long enough to advance the idea that students should be taught that evolution is a controversial theory. Mathews believes this sense of dueling theories will "enliven" classrooms. He states "I think Darwin was right, but boring." By this logic, perhaps we can use Michelle Bachmann's understanding of the Founding Father's tireless fight against slavery to enliven history lessons as well. Valerie Strauss has posted a response to Mathews here.

I taught science for 18 years, and have some strong feelings about this. Evolution is the central organizing principle that guides our understanding of the entire field of biology. We understand modern species based on their history and genetic relationships to one another. This allows us to understand why we have so much in common with other forms of life - even ones that seem very different.

When I taught Life Science to 7th graders in Oakland, I found that evolution allowed us to make sense of the wonderful variety of animals that we studied. Before we went on field trips to the aquarium, we studied the fish we would see. Why do some have markings that look like eyes near their tails? Why are some flat like a pancake, and others shaped like sleek cigars? Each of these adaptations helped one or another species to survive and reproduce, by providing a competitive advantage.

This was not without controversy in my classes. I had students and parents alike challenge me. So I developed an approach that I described here a couple of years ago. In my science class, I explained, we base our understandings on evidence. Whatever we believe can be challenged by new evidence, and is always open to question. This is a different set of ground rules from those in effect at church. There, faith is the basis of understanding. And faith is not about evidence, and not open to question.



I think our students need a scientific understanding of the world, including the theory of evolution. To be clear, while evolution may be "controversial" in the public square, it is by no means controversial among scientists. The theory of evolution is central to understanding how species have changed over time, and is crucial in our understanding of physiology and medicine as well. Even practical sciences such as agriculture rely heavily on evolution to understand how crops and livestock have been bred, and how they interact with pests and pathogens.



What is more, students need to understand the rules by which science operates. Science does not have all the answers, by any means, but it gives us a way to accumulate evidence, test out new ideas, and predict what will happen in the future. This is extremely useful in this world in which our species has become so dominant and destructive as to threaten even the viability of life itself.

But we are seeing a political movement that wishes to misinform the next generation regarding these basic things. It is more than inconvenient to have a climate that is growing dangerously warmer. It threatens the market-based system that drives production ever forward. In the US the output of the economy is expected to grow by 2% to 5% per year - indefinitely! This is absolutely unsustainable given current modes of energy and resource uses, but any scientific data that contradicts this must be undermined and declared "controversial," even if it is completely factual.

The theory of evolution undermines another core value held by some conservatives, who believe that the Christian bible is literally true and ought not to be contradicted. They are entitled to their beliefs, and I respect those beliefs -- but they have nothing to do with science. If we, as teachers, tell our students that there is genuine scientific controversy over the theories of evolution and global warming, we are misleading them about the facts, and also creating confusion about the way science works.



Science is not determined by a popular vote. Scientists work very hard to not only investigate nature, but also to share their discoveries, challenge one another, and build consensus around ideas that have sufficient evidence. There are legitimate controversies in science -- based on disagreements about what the evidence shows. Challenges rooted in religious beliefs are not in this category. The theories of evolution and global warming have both endured rigorous scrutiny - and the scientific consensus is clear.

The proposed law in Tennessee, the state where the Scopes trial occurred 86 years ago, will require science teachers to inject controversies into science that do not belong there. This is a reminder of another reason teachers need protection for their ability to teach their subjects based on their expertise. Our unions are one of the best ways to protect this freedom.

What do you think? Should we "teach the controversies" of evolution and global warming?