Science Myths Unmasked

by Stephanie Chasteen on July 21, 2011

Quite some time ago I was sent a charming little book by its author, David Rudel, with an offer to review it.  Eight months later I finally managed to get through the other items on my reading list and spend some time reading it through   (Let this be a word of warning to all authors expecting me to give any sort of speedy turnaround — though I always do follow through eventually!)

I can’t recommend this book enough.  It’s a gem.  This first volume (Earth and Life Sciences)investigates nine common science myths in depth:

  • Why seat buckles feel hot
  • Cloud formation
  • Mendelian genetics
  • Evolution
  • Why are veins blue?
  • Producers and consumers
  • The far tide
  • The “greenhouse effect”
  • The coriolis effect

Mr. Rudell came across these myths as he worked for Explore Learning creating Gizmos (a pretty good, but for-profit interactive educational simulation).  To create the simulations, which enhance textbooks, he needed to become very familiar with the common texts.  He found so many errors in those textbooks that he undertook this project to provide an alternative (and factually correct) textbook — to help both teachers and former students who have been “betrayed” by these erroneous textbooks.

The book is a slim volume, but I say that he has provided an “alternative textbook” because the level of depth and detail that he provides on each topic is in the textbook style — building up a complete understanding for the reader on each topic.  This detailed approach means that this isn’t light reading, but he provides many helpful summaries and take-home messages throughout.

What was interesting to me, in several instances, was to find that I myself had been the victim of several erroneous depictions of science.  Much of the book is outside my field (which is physics).  I’m particularly weak in biology, and so have never had the opportunity to go much deeper than the survey-level undergraduate course.  For example, in the chapter on Mendelian genetics, he points out that the type of genetics studied by Mendel (e.g., the wrinkled vs. smooth peas) is a rarity in genetic science:  Dominant and recessive alleles are relatively rare, he says.  Additionally, most traits are not determined by a single gene, as the wrinkled/smooth trait is.  Mendelian genetics is a nice story, and an easy way to address the idea of the relationship between genotype (our genes) and phenotype (what we look like), but it’s an over-simplified story.   I realized, reading this, that I had indeed carried this over-simplified model for genetics in my head.

But worse than being over-simplified, he points out, this version of genetics doesn’t support the version of evolution that we teach:

A student reading a typical chapter on evolution in a middle-school book has every reason to wonder how it is possible that genetics could alow the type of infinitesimal changes described.  In Mendel’s experiments, peas were either smooth or wrinkled, they were never semi-smooth.

What is needed to account for this ability for a species to change gradually is the idea of polygenetic inheritance (i.e., a trait that is affected by several genes), and multiple genetic categories (e.g., skin color has more than two options due to multiple alleles and incomplete dominance, allowing for gradual variability).

The chapter on evolution has a similarly illuminating discussion of how we erroneously think of evolution as generating more and more fit species over time as the less-fit individuals fail to breed.  Extinction, for one, plays an important role:

The modern horse is not the summit of a long lineage of horses becoming more fit over time but rather the single remaining species among many viable cousins that lived contemporaneously.

I’m looking forward to the next two volumes, when they come!

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