Casey Luskin offers some thoughts:
That mutation is “directionless” or “random” is a traditional axiom of evolutionary biology. My correspondent wanted to know what it means to consider that some mutations may be “non-random” after all. She supposed that she was asking a “dumb question.”
Exactly the Question to Ask
Actually, it’s not in the least a dumb question — it’s exactly the right question to ask! In the context of this paper, what “non-random” means is that mutations are less likely to occur in gene-coding DNA — especially in what they call “essential genes.” This overturns two standard assumptions of the modern theory of evolution.
In evolutionary biology, it’s generally thought that mutations are “random” in two respects:
Mutations occur with equal likelihood across the entire genome. So there’s no part of the genome that is MORE or LESS likely to experience mutations than any other part of the genome. This is supposed to mean mutations are not directed or concentrated, but in a sense are randomly distributed across the genome. Mutations occur without regard to the needs of the organisms, meaning they are random and not directed for or against what the organisms needs to survive. The Nature study found evidence against both (1) and (2). In Arabidopsis, some parts of the genome are LESS likely to experience mutations, and those parts of the genome that experience fewer mutations tend to be the REALLY important parts of the genome that you wouldn’t want to be mutated because in those sections, mutations would most likely break genes that are very important to the organism.
Casey Luskin, “New Study in Nature Showing “Non-Random” Mutation Spells Trouble for Neo-Darwinism” at Evolution News and Science Today (February 19, 2022)
Darwinism is essentially over as far as the evidence is concerned, as Casey Luskin explains. But it is not over as far as the popular story sold to the public by people whose careers depend on it is concerned. This article in Nature is a foray into honest discussion.
You may also wish to read: Casey Luskin on how the fossil record challenges Darwin. Luskin: One of the largest difficulties with evolution is the word itself. Supporters of Darwinian theory love to switch the word around so the average person can never be sure what they are talking about.