So we’ve established that population is probably an okay metric to use, but I’m still not entirely satisfied. Am I really meant to believe that every multicellular creature ever failed to get ‘being smaller’ as one of its five auto-evo options every, single, time? Is any species whose population is not in the trillions just the result of unfortunate rng?
I don’t think so. I think auto-evo can only properly create species with lower populations if we make a change even more fundamental to the system than a different metric for evaluation. The problem isn’t that it doesn’t know how to pick the ‘best one’ out of its options, the problem is that it is picking the ‘best one’ at all. Let me explain:
Contrary to what catchphrases like ‘survival of the fittest’ might tell you, evolution doesn’t really select for the optimal species. Rather, it selects for the fit enough, anything that doesn’t die before it reproduces. Multicellular creatures, for instance, are doing worse than bacteria, they just aren’t going extinct either.
To further illustrate this, let’s take a look at a scenario that would be common in the auto-evo. A species of microbes develops five different mutations. Auto-evo runs for all five mutations and for the original species, and checks which one has the most population. The variant that does the best is then selected, and the entire species magically gains that mutation!
In reality, this would never happen. Instead, all six variants of the species would exist concurrently. Then, the ones that don’t make it will go extinct, and the other ones will continue to exist. This means that any species that isn’t heading for extinction will continue to exist, no matter how suboptimal they are.
If we tried to make the auto-evo system account for this, it might look something like this:
Step 1: Make 5 different mutations, as before.
Step 2: In the population algorithm, replace a small fraction (say 1% per mutation) of the species with the mutated variant.
Step 3: Run the population algorithm to find out which variants die off (probably because they couldn’t compete with the original), and which ones don’t. The variants that die get yeeted, the other ones become separate species for the next round.
Now, I have the sneaking suspicion that this system will cause a ton of tiny populations to exist. This could be fixed by moving the threshold slightly above zero, to make those tiny populations count as extinct.