Lose the Sweet Tooth

May 27, 2013

One can safely assume that cockroaches are not among the typical urban resident’s favorite animals.  While they are not as dangerous as, say, a malaria-carrying mosquito, or a tse-tse fly, they can potentially transport infectious agents, and have been implicated in some human allergies.  Mostly, though, people just think that they’re gross.  They’re also quite hardy, and able to go for fairly long periods without food or water; getting rid of them can be a chore.

Back in 1976, the Black Flag company introduced a roach trap called the Roach Motel™; it is a small enclosure, which contains a slow-acting poison mixed with a bait.  (Other companies marketed similar products.) The idea is that roaches will be attracted to the bait, and then carry the accompanying poison back to their nests, thereby getting other roaches as well.  The product was quite successful, in part because of aggressive advertising, and its memorable slogan, “Roaches check in, but they don’t check out.”

More recently, though, users have noticed that the traps were becoming less effective. The New Scientist  has a recent article on some research that may explain why.   One of the ingredients in the bait used is the simple sugar, glucose.  It seems that the roaches have evolved a distaste for glucose.

In the race for world domination, cockroaches have scored another point against Homo sapiens. Their weapons? A distaste for sugar and a helping hand from evolution.

In a paper published in the journal Science, researchers at North Carolina State University in Raleigh discovered that some roaches of the species commonly known as “German cockroaches” [Blattella germanica] had a difference in their neurochemistry that caused glucose to “taste” bitter, a trait which they passed on to their offspring.  The use of glucose as a bait in poisoned traps creates selection pressure that favors roaches without a sweet tooth.  Hence, the authors suggest, evolution is at the heart of the traps’ decreased effectiveness.

This kind of evolutionary “arms race” is similar to what we have seen in the development of antibiotic-resistant bacteria, DEET-resistant mosquitoes, and herbicide-resistant weeds.  We humans are quite good, in many cases, at devising ways to modify our environment.  But we too often forget that our environment is not just a passive lump of matter — when we push, it frequently pushes back.

More Legislative Lunacy

August 19, 2012

Reader, suppose you were an idiot. And suppose you were a member of Congress. But I repeat myself.
  — Mark Twain

Mark Twain did not hold legislators in particularly high esteem, a sentiment shared at present by a large majority of US voters.  Congress certainly produces its fair share of daft legislation, but one of the strengths of the American federal system is that the 50 state legislatures can come up with their own, individualized forms of idiocy.   I have written here before about some examples, such as the statute in South Carolina (since repealed) that required subversive organizations to pay a $5 fee to register with the state, or the Louisiana legislation which would require additional penalties if a crime involved the use of maps.   More recently, we have seen the North Carolina legislature forbidding the publication of unwelcome climate forecasts, and legislators in Georgia revealing that pedestrians and cyclists are part of a dastardly UN plot.  The state of Indiana was something of a pace-setter in this regard, with its attempt in 1897 to set the value of the mathematical constant, pi [π], by legislation.

Ars Technica has a report on a new effort in this vein, this time from the state of Kentucky.  It seems that some state legislators were shocked — shocked! — to discover that a standardized achievement test in science had many questions dealing with the theory of evolution in the test’s biology section.

The No Child Left Behind Act of 2001, passed by Congress with bipartisan support in the early days of President George W. Bush’s administration, established a policy of setting educational standards, and measuring student achievement using standard tests.  In 2009, the Kentucky legislature moved to adopt the national standards; the state engaged a testing company, ACT, to develop the written standards and tests.  The results were not pleasing to at least some legislators.

Given that evolution is extremely well supported and provides the central organizing idea of biology, ACT’s tests featured it heavily. That made a number of the state legislators rather unhappy, and gave them the chance to demonstrate that they should not be setting education policy.

A more extensive report, in the Lexington Herald-Leader, reports state Senator David Givens is proposing that creationism (based on a literal interpretation of Genesis, in the Bible) should be given equal time.

“I would hope that creationism is presented as a theory in the classroom, in a science classroom, alongside evolution,” Sen. David Givens, R-Greensburg, said Tuesday in an interview.

Both state and federal courts have ruled that creationism is not science, but a religious belief; it can be taught in a comparative religion class, for example, but teaching it as science violates the “establishment clause” of the First Amendment to the US Constitution.  On August 18, 1986, a group of 72 scientists, all winners of the Nobel Prize, along with 17 state academies of science, filed an amicus curiae brief with the US Supreme Court in the case of Edwards v. Aguillard, against a Louisiana law that mandated the teaching of “creation science”.  The Supreme Court ruled in June, 1987 that the law was unconstitutional.

Another legislator, Rep. Ben Waide (R-Madisonville), has apparently some special insight in this area.

“The theory of evolution is a theory, and essentially the theory of evolution is not science — Darwin made it up,” Waide said. “My objection is they should ensure whatever scientific material is being put forth as a standard should at least stand up to scientific method. Under the most rudimentary, basic scientific examination, the theory of evolution has never stood up to scientific scrutiny.”

This will come as news to the overwhelming majority of biologists (and other scientists), who regard Darwin’s theory as fundamental to the modern science of biology, occupying a place in biology analogous to Newton’s Principia in physics  But then perhaps they are using criteria a bit more advanced than the most basic and rudimentary.

The theory of evolution by means of natural selection is one of the most well-supported theories in science.  It is, of course, possible that, just as Einstein discovered that Newton’s analysis wasn’t quite right, other scientists will discover that Darwin needs a bit of polishing.  But we should remember that, though Einstein made some corrections and extensions, Newton’s analysis works just fine for most everyday problems, and even for sending a spacecraft to Mars.  I think any changes to the theory of evolution will be similar refinements.

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