Wednesday, May 17, 2006

Genie's Tips on Teaching Evolution

Dr. Eugenie Scott directs the National Center for Science Education, a non-profit organization that defends the teaching of evolution in public schools. In a recent talk at PNU, Dr. Scott offered current and future biology faculty important tips on teaching evolution, especially to students who come in with misconceptions about what evolutionary theory is and whether it poses a threat to their religious faith. I will do my best to reproduce these tips here, with the caveats that 1) all credit is due to her and 2) any inaccuracies are my own fault.

Genie's Approximately Ten Top Ways to Teach Evolution Better

1. Convey the idea that evolution is a core scientific concept, repeatedly tested over many decades and found to be both reliable and fundamental. Its basic premise, that all living organisms are descended from a common ancestor, is universally accepted by biologists. The fine details, those persisting gaps in knowledge most commonly attacked by anti-evolutionists, belong properly to the frontiers of science, where models and explanations are actively being tested and are still subject to major changes.

2. Recognize that evolution can be discussed in terms of A) the major concept (organisms change through time and descend from common ancestors), B) pattern (ordering organisms in terms of how closely they are related, i.e., how long ago they last shared a common ancestor), or C) mechanism (the exact genetic changes responsible for observed differences over time). Opponents of evolution often conflate these, acting as though uncertainty as to mechanistic details of a specific case or the precise relationship between a particular set of organisms deals a huge blow to the basic concept.

3. Realize that scientists and laypersons use a number of common terms with very different connotations. A scientific fact is an observation, repeatedly confirmed and accepted as true. A body of these facts can be summarized as a law, a descriptive generalization of behavior under stated circumstances. A hypothesis is a tentative explanation of these generalized observations. Repeated testing of a hypothesis can confirm it as a scientific theory - a well-substantiated explanation of facts, laws, and so forth. So evolution is not "just" a theory - its status as a theory makes it superior in scientific parlance to any of the other terms defined above.

4. Don't conflate methodological materialism with philosophical materialism. Science is limited by definition to explaining the natural world via natural processes. We can only test material forces using scientific methods, and we do this by holding some factors constant and varying others. However, this does not necessarily mean that this material world is all there is. We are capable neither of constraining nor of manipulating supernatural forces. God *could* be involved in natural processes, but we cannot control Her actions, and therefore we have nothing to say about what role She might be playing.

5. Know that scientists and laypersons talk about causation in very different ways as well. We can generally agree on proximate (directly observable) causes - for example, that New Orleans was destroyed by a hurricane. However, while laypersons might proceed to deeper causes such as inadequate building codes, and finally to non-material ultimate causes, such as punishment of a city for its sins, scientists cannot. Our secondary causes are inferred explanations for observed phenomena, and our ultimate causes are still material. The possibility for non-material causation exists, but it lies outside the realm of science, see #4.

6. Be able to explain that evolution is not unique to biology. Its basic concept of change through time applies to all of science, from the birth and death of galaxies to continental drift to the radiation of Romance languages from common Latin roots. It is only opposed so violently in the area of biology because it threatens the comforting idea that humans are different from all other animals, specially created by God in His image.

7. Know what evolution is NOT.
A) It is not an explanation for the origin of life, the spontaneous self-organization of organic molecules into complex systems. This is a very interesting field, but quite distinct and still largely speculative.
B) It is not equivalent to "Darwinism", that bogeyman of anti-evolutionists who present it as an evil atheistic ideology (helped along by certain scientists who confuse their own lack of belief with conclusions capable of being drawn froms scientific observations and methods).
C) It is not "chance" or a completely random process with an infinitesimal probability of success. Evolutionary adaptation is due to the force of natural selection - that is, the differential success of random variation results in some characteristics becoming more prevalent in a population over time. Even complicated organs like the eye can be generated by incremental steps, each successive version an improvement over the last.

8. Be able to clarify the difference between the outmoded "great chain of being" and evolution. Although we commonly speak of modern day organisms as "primitive" or "advanced," they are all the SAME distance from their last common ancestor! All terrestrial vertebrates are descended from a fish-like ancestor that crawled onto land, so we should not expect to find evidence that, say, modern reptiles are intermediate between ourselves and fish.

9. Understand how evolutionary history determines future as well as present. Terrestrial vertebrates have four legs because we descended from fish-like marine ancestors with two pairs of fins. We will never sprout a pair of wings from our backs like Pegasus - we can only convert one pair of limbs to wings as birds and bats did independently.

Well, that was only nine, but Dr. Scott didn't have time for more because she had to dash to the airport right after the Q & A. If I could sum up her message in one phrase, it would be, "Information - not indoctrination." Given a few more words, I would add that our goal should be to produce a scientifically literate populace as well as future scientists. We should recognize the need to set standards for basic science education over individuals' objections - but also to find ways to teach controversial topics without making kids from different belief systems feel excluded or belittled.

Friday, May 05, 2006

Running on Empty

What does it take for the world's largest oil consumer to rethink its gas-guzzling ways? Global warming? A war in Iraq? The perceived necessity of drilling in pristine Arctic wilderness or of maintaining good relations with tyrranical leaders who control the oil supply? Nope, only voter indignation at the price we're currently being asked to pay at the pump. Suddenly the Republicans are falling all over themselves trying to present us with short-term solutions like the now-infamous $100 gasoline rebate without doing much at all to address this problem in the long term.

And the Democrats have no reason for pride on this score either. Senator Richard Durbin (D-IL) introduced a bill called the Automobile Fuel Efficiency Improvements Act way back in September 2005. But thus far, only two Senators, Maria Cantwell (D-WA) and Charles Schumer (D-NY), have been willing to co-sponsor S.1648, which would mandate dramatic improvements in automobile fuel efficiency. This is a bill that the whole party should get behind while the issue has momentum and visibility.

And let's have no more talk of decreasing the gas tax, or distributing gas rebates, or increasing the domestic supply by drilling in the Arctic National Wildlife Refuge. If it takes high gas prices to get our attention - if only short-term financial pain can alert us to the less tangible costs of our oil addiction in climate change, health, and national security - then the current crisis could be the answer to our prayers. Let's use this opportunity to create real changes in U.S. energy policy that will better serve our nation and the world.


The substance of S.1648 is summarized on the Library of Congress' legislative information website THOMAS as follows:

Automobile Fuel Efficiency Improvements Act of 2005

Amends federal transportation law to phase in an increase in average fuel economy standards: (1) from 25 miles per gallon for passenger automobiles manufactured between model years 1984 and 2008 to 40 miles per gallon for those manufactured after model year 2016; and (2) from 17 miles per gallon for non-passenger automobiles manufactured between model years 1984 and 2008 to 27.5 miles per gallon for those manufactured after model year 2016. Requires the Secretary of Transportation to prescribe such standards for non-passenger automobiles at least 18 months before the beginning of each model year after model year 2017.

Revises the definitions of automobile and passenger automobile, increasing the weight standards and seating capacity.

Increases the civil penalties for violations of fuel economy standards.

Requires the Secretary of Transportation to: (1) report biennially to Congress on the quality of the automobile fuel economy testing for all currently available automobile technologies; and (2) provide for the John A. Volpe National Transportation Systems Center to study what practicable automobile fuel economy testing process provides the most accurate measures of actual automobile fuel economy in highway use, in urban use, and in combined highway and in urban use.

Directs the Secretary to prescribe: (1) a revised testing procedure for accurately measuring the actual automobile fuel economy of each automobile model, based on the latter study; and (2) amended average fuel economy standards taking into account improved accuracy in their calculation resulting from use of such procedure.

Revises requirements for the fleet average fuel economy standards for U.S. executive agency automobiles, both passenger and non-passenger.

Directs the President to prescribe regulations that require a specified minimum number of exceptionally fuel-efficient vehicles leased or bought by U.S. executive agencies.

Straight from the Gut

If you haven't yet heard or read Stephen Colbert's recent address at the White House Correspondents Association annual dinner, go to Democracy Now. I mean right now.