Does Evolution of the Genetic Code Undermine a Design Argument?
The genetic code is not absolutely universal or unchangeable. Variants occur, and researchers have proposed evolutionary histories for the standard code.
If the genetic code evolved, does that contradict the claim that biological information bears evidence of design?
Why This Matters
This objection helps us distinguish two questions that can easily become confused: the historical development of a biological system and its ultimate origin.
If evidence shows that the genetic code changed through biological history, a credible design argument must incorporate that evidence rather than deny it.
Response
Variants of the standard genetic code are known. They demonstrate that codon assignments can change under some circumstances.
Comparative and theoretical research also provides models in which coding relationships expand, change, and become increasingly resistant to translation errors.
Evidence that the genetic code evolved therefore tells us something important about its history.
But demonstrating modification of an already functioning coding system is not necessarily identical to explaining the first origin of coding. The modern code may preserve effects of chemistry, selection, coevolution, historical contingency, and common ancestry.
Intelligent Design does not require biological systems to have no history. A system could undergo extensive modification and diversification after its origin. The relevant design question is therefore narrower: what best explains the origin of the functional relationships that made coding and translation possible in the first place?
Question That Remains
How much of the standard genetic code can be reconstructed through known evolutionary processes?
What was the earliest coding system?
Did the coding principle itself emerge through the same mechanisms that later modified the code?
Where should we distinguish the origin of the system from its subsequent evolutionary history?