I’ve been conversing with folks on Peaceful Science about randomness in evolution. I asked them to define randomness.
If you purposefully shuffle a deck of cards the result is
still a random order of cards.
Mathematician Neil Rickert replied:
In ordinary life, “random” is used with a range of different meanings. For biology, particularly evolutionary theory, the main concern is that mutations are random with respect to fitness. And that mostly means that mutations do not seem to be purposely oriented to improve fitness.
If we found that mutations were usually beneficial (improved fitness), that would pose a problem for evolutionary theory, even if the mutations satisfied mathematical tests of randomness. So the use of the term “random” in evolutionary theory is mostly a way of saying that mutations do not appear to have any bias toward improved fitness….
…The traditional account of evolution says that mutations are copying errors. And it looks to me as if you are really arguing about that view of mutations. But random need not imply error…
Random is not the same as erroneous or accidental. I’m suspecting that you (and Shapiro and others) are making a mistake by arguing against randomness of mutations. If you were instead arguing that mutations are not accidents, but are instead part of how the system works, then I would probably be agreeing with you.
Gentlemen, here’s the problem:
Evolutionary events (that generate flagella and eyes and new species and antibiotic resistance) are not caused by copying errors. Nor are they random.
How do I know this?
1) In information theory, randomness is noise. Noise destroys. If, like me, you’ve spent 35 years building communication systems, from amplifiers to networks to e-commerce platforms – you know that noise is ALWAYS your enemy. It wreaks havoc. It is NEVER your friend.
If it were possible to take a self-replicating code-based system, introduce random copying errors and get a better system, software developers would be drooling all over their keyboards.
That’s why the original question I asked about evolution 14 years ago was: “If random copying errors evolve biology, why don’t they evolve software too?”
Turns out, such a notion simply does not exist in computer science. (Or analog or digital signal processing, or networking, or linguistics, or mathematics.)
Random copying errors don’t evolve any system. In biology, however, the systems for writing changes to the genome are so good they don’t merely repair the system. They can also improve the system.
No man-made technology can match this. If we took the time to understand evolutionary adaptations (instead of abdicating to randomness) our technology would reap great benefits.
3) Evolutionary events are generated by what I call the “Swiss Army Knife.” Transposition, horizontal gene transfer, epigenetics, symbiogenesis. Large, expensive textbooks document the non-random behavior of such systems in detail.
To suggest that evolution comes from randomly shuffling broken fragments of DNA like a deck of cards is to pretend the last 50 years of molecular biology never happened. Organisms exert far more control over their genomes than that!
4) Evolutionary events are demonstrably not random with respect to fitness. Their success rate is better than chance alone would ever predict. (Swamidass was gracious enough to start a thread with numerous examples.)
Barbara McClintock created DNA copying errors with radiation. The plant replaced the damaged sequence by copying code from other chromosomes.
She did not have to kill a million corn plants for this to happen. See “Damage is random. Repair is not.”
Her plant was not lucky. It was successful.
McClintock was the first geneticist to observe an evolutionary event AND resolve genetically what had occurred. She won the Nobel Prize for discovering Transposition. Her Nobel Prize paper highlights the extreme contextual sensitivity of cell-engineered mutations.
“Random” – which the Peaceful Science community is still unwilling to define (??!!) has become a rug for sweeping away questions people do not care to answer.
Evolutionary scientists use the word “random” in a sloppy, anti-scientific manner… then ridicule scientists who use the term correctly.
It’s time for that to change.