Criminology, sports drug testing and evolution

DNA evidence in forensics

On March 18, 2013, a Florida man was found guilty of burglary and criminal damage to property, in an attempt to steal an ATM machine from a store. But the burglar had dropped his hat, and subsequent analysis of DNA in the hat matched that of a suspect. Based on this evidence, the jury quickly reached a guilty verdict.

DNA evidence works the other way too. On January 30, 2013, a former Akron, Ohio police captain, who had been convicted of murdering his wife in 1997, was cleared of the crime and released from prison, because comparisons of DNA at the crime scene did not match his DNA.

The public appears to be completely supportive of such actions taken on the basis of DNA evidence. A 2005 Gallup poll found that 85% of Americans view DNA evidence is either completely reliable or very reliable, and, further, that DNA evidence is considered more reliable than fingerprint evidence. Doubtless these figures are even higher today. There are potential lab errors and data handling problems, but by and large DNA tests deserve the trust the public places in them.

Athletic drug testing

In a similar way, the public appears to be very supportive of using scientific drug tests, performed using modern mass spectrometry methods, to determine whether athletes have been using steroids and other banned performance-enhancing substances. In recent years, San Francisco Giants slugger Barry Bonds and Tour de France winner Lance Armstrong, among many others, have been found to have used these substances, and have been censured.


There is a supreme irony in the fact that the public overwhelmingly accepts DNA profiling to convict (or release) criminals, and mass spectrometry to detect banned substances in the urine of competing athletes, yet both of these technologies have been employed for many years in studies of geology and evolution, and, in fact, constitute part of the huge body of evidence in support of the scientific worldview of a 4.5-billion-year-old earth, with an evolutionary development of biological species. Instead, fully 40% of Americans hold that God created the universe, the earth, the sun, moon, stars, plants, animals, and the first two people within the past 10,000 years.

Needless to say, many millions of people are being utterly inconsistent in their approach to science and technology. DNA evidence of exactly the same sort that is used to convict criminals is also used to affirm the very close biological relationship between species. For example, human beta-globin (a component of hemoglobin in blood) is identical to that in chimpanzees, is 99.3% identical to that in gorillas, yet progressively less similar to that in red foxes, dogs, polar bears, horses, rats, chicken and salmon. Also, humans have four transposon mutations in a certain section of their DNA. Bonobos and chimpanzees both have exactly these same mutations, plus one additional one. Gorillas only share three of these and orangutans, two.

Such evidence is multiplied many thousands of times when analyzing the full human DNA genome, and millions of times as scientists examine the rapidly growing online databases of DNA for other species. There is no reasonable explanation for these between-species similarities, except that the species involved in these comparisons are descended from a common ancestor, as proposed by evolutionary theory.


Similarly, mass spectrometers, which are currently the centerpiece of drug testing equipment, have for decades been used for radiometric dating of rock samples. Mass spectrometers measure the levels of certain radioactive isotopes, and this data can be converted into a date of the specimen in question. Over the years, these techniques have become ever more consistent and reliable, and now fully deserve their gold-standard reputation in the scientific community. Tens of thousands of such measurements are in the peer-reviewed scientific literature.

As a single example, in February 2013 U.C. Berkeley researchers, using a state-of-the-art argon-argon scheme that permits a very accurate date determination, found that the Cretaceous-Tertiary meteorite impact occurred 66,038,000 years ago. They separately measured the age of the epoch when the last of the dinosaurs abruptly went extinct; this occurred 66,043,000 years ago. Given that these dates differ by no more than the statistical error bars of the measurements (11,000 years), they are essentially identical. Thus these new findings offer dramatic confirmation to the theory that the meteorite impact caused the extinction (although climate-related phenomena prior to that time may have exacerbated stress on these species).

The importance of education

It is widely thought that the reason so many are so inconsistent in their scientific worldview is that they view evolution as in conflict with the precepts and teachings of their religious denomination. But here, too, the evidence points in another direction. A recent MIT study found that only 11% of Americans belong to a faith that openly rejects evolution. In other words, the vast majority of those Americans who reject evolution cannot cite the teachings of their religious denomination as the reason.

So why the massive inconsistency, on at least three fronts? There is no good answer. But certainly improved scientific education is important now, and will be ever more important in the future. Along this line, in the latest international test score results U.S. eighth graders ranked an unimpressive 12th place worldwide.

What’s more, many teachers in K-12 schools are either themselves unfamiliar with the full strength of evidence behind geology and evolutionary biology, or are being subjected to fierce pressures from parents and, in some cases, timid school administrators.

One way or another, youth need to be better educated. How can we expect the public to correctly understand DNA and drug testing, not to mention geology and evolution, if they have never been rigorously taught these precepts in school?

[This appeared in the SMR blog.]

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