Biology Below The Gnat Line

Biy'allogy - (n) the scientific discipline otherwise known as biology, as taught below the Gnat Line. This blog is for educators who teach science in the deep south, where social and political conservatism reign supreme and "evolution" is a cuss word.

Thursday, January 6, 2011

How Can We Test That?

At the end of the semester my students must demonstrate their ability to think critically and use the scientific method by testing a hypothesis and presenting the results. It's not rocket science. The projects are simple, but must be based on valid observations and testable hypotheses. Usually, the students knock this assignment out of the park. I've been extremely pleased with their presentations and rarely hand out a bad grade.

This is significant because (apparently) I love to give out bad grades.

Many of these students are not science majors, so I hope that by taking my class they learn enough about science to navigate the natural world around them. I want them to process information critically and to think before they form an opinion.  They come to us with some strange beliefs anyway - "I didn't come from no damn monkey!" - and so I spend a lot of time encouraging discussion and clearing up confusion.

Major points of confusion:
  • evolution
  • natural selection
  • gene regulation
  • cancer
  • theory
  • global warming
  • cloning
  • antibiotics
  • hypothesis
The recent rash of mass bird deaths has generated buzz within the community because of the "apocolyptic nature" of the events. Historically, mass animal deaths are not really uncommon, from wildebeest to honeybees, populations can be affected by numerous variables, both natural and anthropogenic. The most famous incident resulted in mass species extinction and may have been caused by an asteroid. People always seem to forget about that one when talking about birds falling from the sky and toads exploding and whatnot. Many valid hypotheses abound regarding the recent rash of birds falling from the sky, fish floating to the surface, and crabs washing ashore. An example of an untestable hypothesis would be, "Apocalypse."

I'd like to blame the humanities for devaluing the word hypothesis, but I don't think that's exactly fair. They could blame me for making up words and ignoring grammar. Indeed, I carelessly wield a vocabulary as dangerous as a butcher's meat cleaver. But in science, a hypothesis must be testable and falsifiable. A theory is a hypothesis for which there are several lines of hard evidence. Unfortunately, people throw around the words "hypothesis" and "theory" to describe guesses and tenuous connections. A man on a commercial flight to Australia once told me, "I don't believe in global warming. It's just a theory." I pointed out the window to the ocean below us, "Theoretical physics gave man the ability to fly. How's that working out for you?"

How do we reconcile these definitions?


  1. LOVE IT.

    While it's somewhat different, I often face a similar rejection of the definition of something like "privilege," in the context of identity. Students can hear the definition of privilege. They can hear examples of privilege (i.e., when I was a kid, Band-Aids came in one color only). But they can't see that they themselves have privilege. Weird.

    Tell me, what is the point of confusion on cancer? 'Cause I'm dying to hear that one...

    PS: This is really Dee, and I don't know why it insists my name is Betty (MiL).

  2. The issue with cancer is twofold: the idea of correlation and the idea of mutations. At the heart of it, cancer results from a failure in gene regulation. The gene that says "DIVIDE NOW!" is turned on (or up) and the gene that says, "STOP NOW!" is turned off (or down). There are things you can do to throw this out of whack yourself, and those relate to risk factors. Toxins, UV radiation, hormone imbalances... they can all lead to abnormal cell growth due to changes in gene regulation. But just because you smoke doesn't mean you WILL get lung cancer, and just because you don't smoke doesn't mean you won't get lung cancer. A series of mutations in the DNA could also result in the changes in gene regulation needed to "turn on" cancer.

    It's a complicated topic anyway, made worse by the fact that people don't understand the difference between cause and correlate. Worse, there are groups of people who believe that cancer is a punishment from God. I can't even begin to deal with that.