Evolution: Fit for science
There was a clear lack of understanding of evolutionary theory, and the nature of science itself, in the "Challenging evolution" letters (C&EN, April 18, page 6). Evolution is a scientific theory. Like all theories, it is an overarching set of explanations that has been well-substantiated by scientific evidence published in tens of thousands of papers, in this case explaining how life has developed and changed on Earth. Evolution provides a framework for understanding how organisms appear and change through modifications in genetic composition during successive generations subjected to natural selection.
Absence of a creator is not requisite for this development to occur. Indeed, many of the mainstream Christian denominations have issued statements indicating that evolutionary theory is not incompatible with the teachings of their faiths. Any scientist (whether believer or agnostic) reading the pages of Science, Nature, Proceedings of the National Academy of Sciences, or the myriad other peer-reviewed scientific journals, or walking through a museum, zoo, aquarium, or his or her own backyard, will find more than enough evidence to support evolutionary theory.
Evolution is actually one of the more robust scientific theories, garnering support from a spectrum of scientific disciplines (including chemistry). This evidence ranges from an increasingly clear paleontological record of progressively different but interrelated lineage, all the way to modern-day human, animal, and plant bacteria that have become increasingly resistant to once-effective antibiotics.
Tina M. Masciangioli
I noticed that not one of these letters decrying evolution observed that a belief in God is not incompatible with believing in evolution, any more than a belief in gravity is. The ultimate source of gravity may be a divine finger pressing down on us, but the theory of gravity still holds fine. As chemists, you are fortunate that the Bible doesn't say anything about molecules, or you would have a similar pointless battle to pursue. Can you imagine the organic chemistry class where the religious viewpoint (however you wish to disguise it) is presented as an equally valid account of what is happening?
Incredulity and a perceived conflict with one's religious beliefs are not scientific reasons to discount evolution. Moreover, evolution accounts for the diversity of species, but it does not explain how life came into existence in the first place, as many of its opponents confusingly suggest. Evolution, as a scientific theory, is falsifiable. One modern-day monkey fossil found in a 4 billion-year-old rock is sufficient to knock it down. Intelligent design is not falsifiable and is not comparable to a falsifiable scientific theory. Intelligent design should be taught in a religion or philosophy class and compared to other such ideas.
Scientists, when interpreting the world around them, should leave their political and religious beliefs at home.
New York City
I was somewhat taken aback by the attacks on the arguments for evolution. I can understand those people who, because of their faith, have doubts about that theory, and I would support their efforts to try to justify, scientifically, an alternative theory.
What struck me, though, was the undercurrent of fear that was expressed in some letters. I am always puzzled by this, for if their faith is so strong, what do they have to fear from those of us who disagree with their concepts?
La Paz, Mexico
The "challenging evolution" letters did not elaborate on the weaknesses of intelligent design in accounting for life on Earth. Scientists should not merely defend evolution; intelligent design presents a tempting target because of its lack of explanatory power. The scientific study of biology reveals that existing species possess serious flaws, which belie claims of a beneficent creator. Intelligent design advocates downplay vestigial organs and limbs, anatomical inefficiencies, destructive mutations, and the sheer wastefulness of natural processes.
For example, paleontologists have proposed that whales evolved from land mammals with legs. Evolution predicts that legs would be found in fossilized whales. In recent years, the evolution of whales from now-extinct land animals has been well-documented through newly found fossils from the Eocene. The fossilized whales contain well-defined feet and legs. In modern adult whales, the front legs have evolved into flippers and the rear legs have shrunk so that there are no visible appendages. Hind limbs still appear in the fetuses of some modern whales but disappear by adulthood. Evolution accounts for these useless, vestigial elements as leftovers in the development of whales from land mammals, but intelligent design cannot account for them.
Anatomical inefficiencies occur in all living forms. In humans, the openings of tubes for breathing and swallowing are so close that we often choke. In men, the collapsible urethra passes through the prostate gland, which enlarges later in life and impedes urine flow. Useless nipples occur in male primates.
Many other examples may be cited. An intelligent designer would create only successful species, but evolution alone accounts for the many unsuccessful ones. By being able to account for everything by divine edict, intelligent design explains nothing.
Palo Alto, Calif.
The debate between evolution and intelligent design is of great interest to me as a person of belief and a scientist. To me, the inconceivable complexity of life in this world that has come about in a finite time frame is a clear sign that the rules governing the universe are due to an intelligent designer and an intent for creation in all its manifestations. The acceptance or not of this sign is a matter of personal decision. In any event, it should be agreed that investigating and determining the rules governing the universe--natural law--are a matter for science, and the divining of the purpose thereof, and its ramifications, are a matter for religion.
As to evolution, for the sake of discussion, why could it not be the tool of the intelligent designer?
William S. Durrell
Palm Harbor, Fla.
Fine. teach intelligent design. But then I want equal time for the theories of incompetent design and malevolent design. What kind of intelligent designer would have given us our appendixes and bad backs?
Howard J. Wilk
Evolution is just a theory, and it will remain so indefinitely, but evidence keeps piling up in its favor. The only argument for intelligent design seems to be that it is, according to letter writer Raymond S. Martin, "an absolutely valid explanation of the observed facts." The same might be said for Sir Fred Hoyle's persuasive argument that we were periodically seeded from space. Fundamentalists once dismissed the fossil record as a deception by the devil. Wasn't that also a valid explanation?
No scientist from the 18th or 19th centuries said that we have "the whole world figured out," but they tried to explain things without recourse to the supernatural. That's what science is all about. I see intelligent design as a pathetic, last-ditch attempt to keep God in the picture. If we were to go back 400 years, we might find your intelligent design correspondents more occupied with refuting the troublesome idea of a sun-centered universe.
Floral Park, N.Y.
I was completely dumbstruck on reading "Challenging evolution." I had thought that in this age of enlightenment, when all the sciences, from anthropology to zoology, support the idea of Darwinian evolution, supposedly educated scientists could not deny its validity. Ignoring all the other sciences, just the work done with DNA tracing should be convincing. I can understand how someone ignorant of these disciplines could turn to an idea based on pure faith, with no supporting evidence except a book written a few short millennia ago, constructed from word-of-mouth tales and edited and reedited by numerous councils of men, but someone versed in the scientific method? Never.
The idea that intelligence created what we know of life is also ludicrous. Take the grotesque organisms that have arisen and, for the most part, live for a short while and then die out. Why would an intelligent designer be so inefficient? Why make a creature and destroy it? Why design death? Why make one organism to feed on another? The unanswerable questions that arise from this philosophy relegate it to the realm of pure imagination and wishful thinking.
It is true that there are unanswered questions about evolution, such as missing transitional organisms and provable mechanisms for change, but finding these depends on chance encounters in a wide world of potential sites. More and more is being discovered, and the gaps are being filled. On the other hand, intelligent design has nowhere to go. No proof will ever develop, no evidence appear. It is truly an idea built only on faith, and it has no place in the world of science.
Martin L. Kantor
Reading such letters makes me wonder where these so-called scientists have been living for the past hundred years. It is enough to make you want to tear your hair out and scream alongside the fossils described in Rudy Baum's excellent editorial (C&EN, Feb. 7, page 5).
I would suggest that such individuals read an article that appeared recently, "Ancient DNA from giant extinct lemurs confirms single origin of Malagasay primates" (Proc. Natl. Acad. Sci. USA 2005, 102, 5090). More than 50 distinct species of lemur have descended from a single common primate ancestor that colonized the island of Madagascar sometime in the Tertiary. This is Darwinian evolution at work, folks. Perhaps the intelligent designer is intelligent enough to set things in motion and then sit back and see how things play out.
Few topics arouse such intense passion as evolution. At the risk of further stirring the pot, let me add some ideas that have come from the field of complex systems research in the past 25 years. As systems become more complex and nonlinear, behavior can arise that is consistent with, but not predicted by, the components that constitute that system. An automobile has behaviors consistent with those of the metals, polymers, and electronics that make it up, but there is nothing evident in the raw materials that make an automobile inevitable. A car is indeed intelligently designed. But it doesn't emerge spontaneously. Self-organization, in contrast, can lead to complex spatiotemporal structures without templates--spontaneous emergence, consistent with statistical mechanics but without algorithmic design. Protein folding (with or without chaperones) is an example.
Why do complex biological structures occur? To a Darwinian, it's just chance, amplified by success or (in hindsight) utility. To a proponent of intelligent design, the designer reaches out and tweaks the probabilities (à la Maxwell's demon) and decides which of the nearly equal possibilities to select. Under some circumstances for sufficiently nonlinear processes in a noisy environment, one can demonstrate (as J. Henri Poincaré did for planetary motion 100 years ago) that one can't tell the difference between the two possibilities. The difference between evolution and intelligent design is that evolution is a theory that makes testable predictions and leads to productive conclusions (such as explaining the emergence of antibiotic-resistant organisms). I have yet, though, to hear of a prediction or experiment that has come from the intelligent design viewpoint. Further, evolution was deduced from observation, but its detractors, in my experience, start from belief, not theory or measurement.
Intelligent design is apparently useless (except as a religious philosophy), while evolution could easily be a tool, along with quantum electrodynamics, relativity, and statistical mechanics, of an intelligent designer. For intelligent design to be taken seriously outside religious circles, its proponents must quit sniping at evolution and start devising experiments whose outcomes evolution predicts either differently or not at all.
A question of ethics
Your article on possible ethical lapses during scientific investigations is thought provoking (C&EN, June 27, page 50). If one-third of the responding scientists admitted to unethical behaviors, one can only imagine how pervasive the problem really is. Perhaps it is only human to err in this manner. I hope that scientific journals, along with the funding agencies, can help curb the problem now that it has been identified as a problem.
I would suggest the following:
We maintain records in all other areas of life, so why are academic scientists not held to the same standard? Yes, there should be free thought and the generation of new ideas, but it would not hurt to have to write it down, too. Kudos to ACS for approaching the topic and initiating a dialogue in the right direction. Self-policing and correction at this stage are the right things to do; otherwise, society may lose faith in the scientific endeavor.
Aparna S. Kolhekar
Spinning in his grave?
I read Paul J. Schmidt's review of "Five Quarts" by Bill Hayes with interest, but also with dismay (C&EN, July 11, page 38). Perhaps it was my minor in German literature (balancing a major in chemistry), but the phrase "German philosopher Wolfgang Johann von Goethe" shocked me.
Goethe's name was Johann Wolfgang von Goethe, and though he is extensively quoted on countless topics, he isn't considered primarily a philosopher (the Germans have contributed lots of those in the big-league category). Most knowledgeable scholars rank Goethe as the preeminent poet and author in the German language. We shouldn't mess up his name.
Scott C. Mohr
Human test data: Essential and safe
In "EPA To Okay Human Tests Of Pesticides," Bette Hileman discusses potential Environmental Protection Agency guidance on using human volunteers in the testing of chemicals used as pesticides (C&EN, July 4, page 9). The value of human data is underestimated.
Human studies are invaluable for responsible regulation of chemical technologies, including pesticides. Ethical human tests of pesticide products remove the uncertainty introduced by models that have not been validated and extrapolations from laboratory animal tests, much as the pharmaceutical industry relies upon similar tests for their products in healthy human volunteers with no intention of benefiting those volunteers.
Chemicals used as pesticides and disinfectants and many substances intended for residential use are vital for public safety. Those who provide these products are required by EPA to submit studies conducted with human subjects exposed to chemicals at label rates that are well below levels of concern, in order to support regulatory decisions for registration and reregistration. There is no avoiding the reality of unintended or inescapable human exposure as a result of use of these products, and responsible risk assessment requires scientific studies to ensure safe use. The protocols for these studies have been established during the past 50 years, and the results continue to document that adherence to labels results in exposures that are less than "no observed adverse effect levels."
The Food Quality Protection Act (FQPA) of 1996 (not 1986, as reported in the article) requires comprehensive assessment of pesticide exposure, dose, and effects. In particular, FQPA directs EPA to consider exposure to potentially sensitive subgroups in the population, coincident dietary and nondietary (that is, aggregate) exposure, and concurrent multichemical (that is, cumulative) exposure for pesticide risk assessment. To implement FQPA, EPA has been developing new methods and models to assess aggregate pesticide exposure that could occur in community settings. Human biomonitoring that is intended to establish doses biologically sums available environmental chemical levels (food, water, air, and so on), which would inevitably lead to inflated and misleading estimates of human exposure.
The pictured mosquito control truck is an inappropriate illustration. Human studies are not about "dosing," with pesticide "spewing" from the back of a truck. They are about low pesticide exposures relative to harmful amounts--below "no observed adverse effect levels"--to which we are all intermittently exposed. Knowledge of these levels of human exposure are essential for responsible pesticide regulation.
Chemists without borders
We are pleased to write a follow-up to the letter "An ailing cure" (C&EN, Sept. 13, 2004, page 2). The suggestion to participate in an organization of chemists analogous to Médecins Sans Frontières has catalyzed the conception of "Chemists without Borders." We have started to organize chemists to help make the world better through chemistry, initially focusing on existing vaccines, as mentioned in the previous letter.
We invite other chemists and scientists to contact us and help us grow this organization into an internationally effective humanitarian relief organization. We will promote and facilitate the funding and implementation of chemical technologies to help where they are needed most. More information can be found at www.chemists withoutborders.org.
Royal Oak, Mich.