Microbiologist Carl Woese is well known as an iconoclast. Indeed, few biologists have so thoroughly shaken the tree of life as he did when he proposed that there are not two major branches -- prokaryotes, whose cells lack nuclei, and eukaryotes who possess nuclei, including all animals, plants, fungi, and protists -- but rather three. "Prokaryotes", Woese argued, do not represent a cohesive category, and should be split into two deeply divergent lineages: the Bacteria, with which everyone is reasonably familiar, and the Archaea, superficially similar organisms that are less commonly encountered as many of them reside in extreme environments. What's more, studies of genetic data suggested that the Archaea are actually more closely related to eukaryotes -- including humans -- than they are to bacteria. Three-domain tree

Woese's three-domain tree of life. From Wikimedia Commons.

At 79 years of age, Woese is still shaking things up. Most recently, he stated in an interview with Wired that,

My feeling is that evolution shouldn't be taught at the lower grades. You don't teach quantum mechanics in the grade schools. One has to be quite educated to work with these concepts; what they pass on as evolution in high schools is nothing but repetitious tripe that teachers don't understand.

Woese is no supporter of so-called "alternatives" to evolution, and has no patience for "any intrusion of religious ideas in the name of science". Rather, his point is that evolution -- the foundational principle of modern biology -- is too complex to be dealt with reliably at junior levels, and should be introduced at the college level where it can be addressed more appropriately.

Woese's proposal surely will raise the ire of many scientists and teachers alike. And while I disagree strongly with his conclusion, I am sympathetic to the frustration apparent in his premise.

In addition to carrying out research in genome evolution, I teach an upper-year university course in evolution. In that capacity, I interact predominantly with biology majors who have completed a minimum of two years of undergraduate education in the life sciences. This means that I can expect them to possess at least a working understanding of genetics, cell biology, anatomy, physiology, and ecology by the time they get to my course. I then have almost 30 hours of lecture time to explain the basics of evolutionary theory to them. I like to think that my students leave the course with a reasonable comprehension of evolutionary science, but when we part company at the end of the semester we all know that ours has been an exercise in surface-scratching at best.

In fact, much of my effort is devoted simply to clarifying serious misconceptions about evolution that these educated young adults inevitably bring with them to the class. Each semester, I fully expect many upper-year biology majors to be surprised to learn, among many other examples, that:

  • Humans are not descended from chimpanzees.
  • Scientific theories are well-supported explanations of scientific facts.
  • Individual organisms do not evolve in response to environmental challenges.
  • Animals do not do things for the good of their species.
  • Natural selection is the opposite of random chance.
  • Not every feature of an organism represents an adaptation.
  • Vestigial does not mean non-functional.
  • Modern frogs are not more closely related to modern fishes than mammals are.
  • There is no progressive pattern in evolution leading to humans as the pinnacle.
  • Although humans are now the only living members of the group, several species of hominids co-existed in the past.

My experience in this regard is not unique. In an article published in the scientific journal Evolution in 2002, Brian Alters and Craig Nelson noted that the issue of false preconceptions about evolution is a major barrier to understanding among students. Various studies show that students tend to misunderstand basic concepts such as natural selection and phylogenetic trees, and that this impacts their ability to correctly absorb new information about evolutionary biology.

Woese evidently believes that many of these misconceptions stem from the cursory or even inaccurate treatment of evolution at the high school level. His solution, as noted, is to leave evolution out of early education if it cannot be dealt with adequately, and to leave it to people like me to introduce the topic in a more advanced way to undergraduate students.

An obvious objection to this suggestion is that only a tiny minority of people will ever enroll in a university course in evolution. This means that most people would receive no education in the subject whatsoever and would instead develop their (mis)understanding of the topic based on what others tell them outside of an academic setting. In many cases, this would mean that their view of evolution would be instilled by anti-evolutionists, whose grasp of the science generally is non-existent. Of course, this is already far too common a condition -- and one for which a proper education is the only available antidote. Given how important evolutionary ideas are both in modern biology and in an increasingly broad spectrum of socio-economically relevant applications from combating pathogens to conserving biodiversity, a policy of intentional ignorance is not only academically irresponsible, it is dangerous.

Evolution is undoubtedly a special case in light of the (non-scientific) controversy surrounding its accuracy as an explanation for the diversity of life, but it is not entirely alone. Physicists have also noted that basic concepts in their field are often poorly understood among incoming students. For example, it has been shown that many students maintain the more intuitive views of motion proposed by Aristotle rather than the accurate interpretation provided by Newton, sometimes even after an attempt has been made to correct these misconceptions. This would not be an argument for removing basic physics education from high school, it would indicate that additional effort should be spent on clarifying such misunderstandings as early as possible. So it goes for evolutionary biology.

High school teachers have an opportunity to exert a profound influence on how well their students understand the world around them. Scientists have a responsibility to help them do so. Fortunately, more and more bridges are being built across the divide between scientists and teachers. Examples include the newly developed journal Evolution: Education and Outreach, the outstanding Understanding Evolution web resource from the University of California Museum of Paleontology, and numerous free publications from the National Academy of Sciences.

The problem of misconceptions about evolution is clear. However, omitting this critical component from junior education is no solution at all. What is needed is just the opposite: a renewed effort to properly convey some of the general ideas to students at a level that is both comprehensible and accurate. Time spent directly addressing and clarifying the most common misconceptions about evolution would be well invested, and would require no distorting simplifications of the topic.

If students could be liberated from entrenched misconceptions of humans descended from chimps, organisms changing to meet perceived needs, or complex organs arising by chance, then a good deal of progress will have been made.