Original article: Studies on Slack

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Proposition: If you have enough free resources you can evolve irreducibly complex features.

Imagine a bunch of yeast cells added to a barrel of malt when beer is being brewed. They have an ocean of free resources at their disposal. Surely, the evolutionary pressure will be low and the yeast cells would be able to escape the local minimum and evolve an irreducibly complex eye.

Where this idea fails is not taking the nature of exponential growth into account. Exponential means being fast. It means, in fact, being faster than anything you can visualize. The barrel would be fully fermented in just couple of days.

In other words: No matter how big a whale fall is, it will be exploited fast. The body of the whale will be eaten in months and the last bacterial remains of the ecosystem will survive for maybe 100 years. Nowhere near the time needed for a complex evolutionary change to happen by chance.

It's worth looking at E. coli long-term evolution experiment here. Since 1988 E. coli is cultivated in a uniform substrate and observed to see how it evolves. From our perspective it's interesting that each day 1% of population is transferred to a new flask with the fresh substrate. One can think of it as of a new whale fall every day. Unfortunately, I am not aware of a control experiment where substrate would be added gradually, which would allow us to see whether environment with slack is more conductive to evolution of new features than environment without slack.

However, in one of the populations in the experiment a speciation event was observed. There's one strain of E. coli that has advantage during growth on the substrate (slack) and another strain that has advantage during stationary phase, when the substrate runs out (moloch).

That hints that supposed slack may not be slack at all, just a different environment exploited in competitive manner by different subset of species (ecological opportunists).

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Proposition: Isolation of small subpopulations can produce slack.

Let's start with some basics of population genetics so that we have tools to understand what's going on.

Let's say no human being is able to roll their tongue. What happens when a mutation arises that gives one that ability?

Well, if rolling your tongue makes you more likely to survive and have more children then the trait will be actively selected for. The frequency of

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kinginthecastle

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