Orgel’s Second Rule and toxicity — again.

Some time ago, I posted about a story involving frogs and snakes in which an author of the study was quoted as saying that:

In evolutionary terms, the snake’s strategy of ‘bite, release, and wait’ is unbeatable by the frogs. Although prey often evolve ways of overcoming predator tactics, the frogs can’t do so in this case – because the snake’s strategy only becomes effective after the frog has died. Natural selection ceases to operate on an individual after that individual’s death, so frogs will probably never evolve toxins that last longer in response to the snake’s tactic. Thus, this waiting strategy is likely to be stable and unbeatable over evolutionary time.

I mentioned Orgel’s Second Rule — “evolution is cleverer than you are” — and provided a list of seven possible scenarios which would refute the claim that a response could never evolve in frogs.

Today in ScienceDaily there is another example of a toxicologist who does not get Orgel’s Second Rule. In this case, it is toxic newts and garter snakes. The newts are extremely poisonous in some regions, which is a result of an arms race between them and snakes that feed on them. While there is often an escalating interaction with no net gain for either side in an arms race, in some locales a particular mutation has made snakes completely resistant. Here is what the story notes:

In most locations, the snakes’ level of resistance closely matched newt toxicity. In such cases, the poison temporarily slows the snakes down but isn’t enough to kill them. This supports “arms race” theories explaining how toxicity and resistance co-evolve.

But in some areas where newt toxicity was relatively high, the poison had no measurable affect on snake mobility.

The team found that resistant snakes had a single genetic mutation on TTX receptor sites on their neural and muscle cells, which prevented the toxin from binding. It made snakes with this mutation “untouchable”.

It is pretty much biologically impossible for the newts to ever catch up,” Hanifin says.

Compare this with what is stated in the abstract of the actual peer-reviewed paper:

This coadaptation proceeds until the evolution of extreme phenotypes by predators, through genes of large effect, allows snakes to, at least temporarily, escape the arms race.

I wonder if a reviewer, knowing Orgel’s Second Rule, made them insert the “at least temporarily” caveat.


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