Evolution Requires Pre-Existing Variation

A pet peeve of mine- the suggestion that an animal or an organization or any complex system can evolve to become better adapted.

I ran across this today in an otherwise interesting discussion of life beyond the earth’s environments:

SETI: Why extraterrestrial intelligence is more likely to be artificial than biological | Space

AI may even be able to evolve, creating better and better versions of itself on a faster-than-Darwinian timescale for billions of years. Organic human-level intelligence would then be just a brief interlude in our “human history” before the machines take over. So if alien intelligence had evolved similarly, we’d be most unlikely to “catch” it in the brief sliver of time when it was still embodied in biological form.

I’m interested in this question of whether what is called artificial general intelligence is possible and if so, what form would it take. What bothered me here was equating AI evolving with creating better versions of itself. That’s not evolution; that’s merely improvement.

There’s a real argument to be made that fundamentally an algorithmic process can’t get outside of itself to ever be better than it was originally programmed to be. As argued in this paper, there may be fundamental limits on artificial general intelligence as long as we try to create algorithms limited to a particular problem space

We show that it is impossible to predefine a list of such uses. Therefore, they cannot be treated algorithmically. This means that “AI agents” and organisms differ in their ability to leverage new affordances. Only organisms can do this. This implies that true AGI is not achievable in the current algorithmic frame of AI research. It also has important consequences for the theory of evolution. We argue that organismic agency is strictly required for truly open-ended evolution through radical emergence.

Real evolution in the natural world demonstrates, I think, that there’s no fundamental limit as long as we build in variation so that novel forms of the algorithm are tried and can be selected for against a real ecology independent of the algorithm.

So remember, evolution needs both pre-existing variation and selection of the best adapted variants. You can’t evolve, you can express differences that the world will choose from.

On the other hand, we can see this going on right now.

Ed Yong is one of our best working science writers. This article so clearly lays out how evolution occurs all the time, right before our eyes. The story is that there is a gene for brittle tusks being selected for in the population because tuskless elephants have a survival advantage in an ecology with ivory poachers.

African Elephants Evolved Tusklessness Amazingly Fast

Campbell-Staton’s team has “done a convincing job showing that the Gorongosa elephants have evolved in response to poaching,” Kiyoko Gotanda, an evolutionary biologist at Brock University, told me. Usually, evolution is a slow process, but it can proceed with blinding speed.

I’ll give Dr. Gotanda some leeway here because he said the elephants “have evolved” which is a passive construction, since obviously the elephants didn’t actually do anything to evolve. Well, actually what they had was a pre-existing genetic variation that caused loss of tusks. Had that gene not been there, no selection could have occurred. It’s the part of evolution often forgotten. Variation is extremely valuable to a species because it allows for very rapid adaptation to a changing ecology.