A reader sends along an article from earlier this week by science journalist Matt Ridley, writing in the London Times (“Gene editing isn’t a slippery slope to eugenics“). Ridley says:

At a seminar today to mark [Francis] Crick’s centenary at Cold Spring Harbor Laboratory in New York, hosted by his famous collaborator Jim Watson, I shall argue that the genetic code was the greatest of all the 20th-century’s scientific discoveries. It came out of the blue and has done great good. It solved the secret of life, till then an enigma: living things are defined by the eternal replication of linear digital messages. It revealed that all life shares the same universal but arbitrary genetic code, and therefore shares common ancestry, vindicating Charles Darwin. [Emphasis added.]

The reader asks about that last sentence. Does a “universal but arbitrary genetic code” prove common descent and thereby “vindicate Darwin”?

No. This is a longstanding argument for common ancestry, but you need to understand three things. First, the code actually isn’t universal. See here:

• Reply to NCSE on Universal Genetic Code

• Reply to Kenneth Miller on the Genetic Code

Second, the argument wrongly assumes that the code could evolve naturally in the first place. Third, it assumes that there’s no other way to explain the presence of a shared code other than common ancestry, ignoring the hypothesis of common design.

The textbook Explore Evolution: The Arguments For and Against Neo-Darwinism deals with the underlying science, focusing on the first and second of these points. See there for more detail in the chapter on “Molecular Homology.”

Douglas Theobald, a biochemist at Brandeis University, made a very similar argument in a paper in Nature a few years ago (“A formal test of the theory of universal common ancestry“). Our old colleague Casey Luskin addressed it in three posts here at Evolution News:

• Douglas Theobald Tests Universal Common Ancestry by Refuting a Preposterous Null Hypothesis

• Douglas Theobald’s Test of Common Ancestry Ignores Common Design

• But Isn’t There a Consilience of Data that Corroborates Common Descent?

Ridley’s assertion is a commonplace, having been made numerous times by evolutionists over the years. There are other ways to argue for common descent (see John West’s post “Debating Common Ancestry“), but as you see, this one falls short.

And indeed one might add that neither a universal code nor common ancestry would, if accepted, vindicate Darwinism since the really contentious and problematic aspect of evolutionary theory is its proposed unguided mechanism.

Image credit: © flocu — stock.adobe.com.