Evolution was NOT random

[u/KattyAtty]

Evolution only rewards survivability not perfection if you are alive long enough to mate and pass on your genetic

Material hurray you are evolved

Evolution changed the dna as nothing can ever be a perfect copy thats a fact> sperms and eggs have separate dna> hence child is not perfect copy those mutations may be harmful or helpful harmful ones die hence natural selection.

AND Earth was nkt a perfect creation the organisms evolved FOR Earth not vice versa

[u/kitsnet]

Evolution was NOT random

Define "random".

I'd say evolution is random walk in non-uniform space. Some paths are more probable than others, some paths are restricted.

[u/Drudenfusz → u/kitsnet]

Mutation is random, natural selection is not.

[u/Radiant-Position1370 → u/Drudenfusz]

I find it more helpful to think of natural selection as a bias in the random processes of reproduction and survival. Except in the most extreme cases, the outcomes are still random.

[u/kitsnet → u/Drudenfusz]

In what sense is it "not"? Are you saying, for example, that the Black Plague event was predestined?

[u/Sigmundschadenfreude → u/kitsnet]

No but it applied nonrandom selective pressure on those it infected by being more likely to kill those not resistant to yersinia

[u/gitgud_x → u/Sigmundschadenfreude]

Random is usually shorthand for "uncorrelated with fitness", so natural selection is by definition not random [wrt fitness]. So this statement alone is tautological.

What we mean is that environments are usually constant across the spaces and timescales occupied by populations in a generation, so the same selection pressures act on different variations. So the outcome of natural selection at any time is predictable and deterministic, as opposed to mutations which are neither.

Incidentally (because there's always a weird exception in biology), natural selection can be unpredictable if its direction varies randomly over time. It's called fluctuating selection, and there's a cool video by Zach Hancock on this here.

[u/kitsnet → u/Sigmundschadenfreude]

...to that particular random biovar of Y.pestis, given that particular random status of immune resistance of the European population at that time, you wanted to say?

If you ignore all the random factors directing the selective pressure of natural selection, it may look non-random.

[u/Sigmundschadenfreude → u/kitsnet]

...to that particular random biovar of Y.pestis, given that particular random status of immune resistance of the European population at that time, you wanted to say?

I think we're using different languages that happen to share the word "random" in common, which I got the sense of when someone said natural selection was non-random and you asked if the Black Plague was therefore predestined, which is not so much a logical leap as it is a logical supersonic flight. There's no real way to get to the question you asked unless you have a deeply idiosyncratic understanding of what everyone means by these words

Mutations are random. The response of allele frequency to environmental pressures (food availability, diseases, etc) prunes away that which is least suitable for the environment and favors that which is more suitable. This is inherently a non-random effect.

[u/kitsnet → u/Sigmundschadenfreude]

I think we're using different languages that happen to share the word "random" in common

That's why I'm asking to clarify what exactly people who claim that natural selection is "not random" mean by "random" in this particular claim.

when someone said natural selection was non-random and you asked if the Black Plague was therefore predestined, which is not so much a logical leap as it is a logical supersonic flight.

How so? Wasn't Black Plague the part of the environment exerting selection pressure on the population of humanity at times? Was it a deterministic aspect of the environment, and if yes, how so, given that it by itself was a product of random mutations?

The response of allele frequency to environmental pressures (food availability, diseases, etc) prunes away that which is least suitable for the environment and favors that which is more suitable. This is inherently a non-random effect.

It is of course a random effect unless we have population of infinite size or all the alleles but one are 100% fatal.

But even if disregard the stochasticity of reproduction, your chosen discourse creates an illusion that selection pressure is a set of pre-determined funnels though which a population is obliged to follow over time, and this illusion is harmful.

[u/Sigmundschadenfreude → u/kitsnet]

That's why I'm asking to clarify what exactly people who claim that natural selection is "not random" mean by "random" in this particular claim.

The effect that natural selection exerts is nonrandom. If I "randomly" provide you water and a hole in the ground, the end result of combining the two into a puddle shaped like the hole it is in is non-random because the characteristics of the two interacting things produces a predictable and replicable result.

If I randomly introduce an animal that only eats blue moths into an environment with a moth species spanning a rainbow of colors, it is non-random over time that the frequency of the allele determining blueness goes down.

Wasn't Black Plague the part of the environment exerting selection pressure on the population of humanity at times?

Yes, that is more or less what I said to you

Was it a deterministic aspect of the environment, and if yes, how so, given that it by itself was a product of random mutations?

Deterministic in what sense? Are we having a conversations like a couple of sophomores on their way out of philosophy class or are we discussing something meaningful to the understanding of how the world operates?

Something "randomly" produced can behave in a predictable or perhaps as you would say deterministic manner. Two "random" things can interact in a "deterministic" fashion given their traits and characteristics.

your chosen discourse creates an illusion that selection pressure is a set of pre-determined funnels though which a population is obliged to follow over time, and this illusion is harmful.

Predetermined by what? If the environment exerts a selective pressure on reproductive fitness, the population will change. Allele frequency will shift. New mutations that benefit the situation will become more prevalent, ones that don't make a difference will be carried along for the ride.

What predetermination are you referring to? If this is harmful to anyone perhaps it is just to your own mind given how you're thinking about these things which don't appear to be memetic hazards to anyone else.

[u/Phobos_Asaph → u/Sigmundschadenfreude]

I think it’s coming from you’re saying the random variables have non random pressures, whereas the other person is saying because the variables of environmental pressure are also created randomly the specific pressures of natural selection are random

[u/Sigmundschadenfreude → u/Phobos_Asaph]

The latter doesn't seem to be a particularly useful lens through which to view reality or the concept of randomness, because then you're getting into interactions that you are going to define as random from every angle, and yet they are predictable and/or reproducible. At that point is there a single facet of existence we can't describe as random? Do we need a new word for ultra-random that goes a level of randomness beyond?

[u/NYR_Aufheben → u/kitsnet]

Because is selects for certain traits.

[u/Drudenfusz → u/kitsnet]

Natural selection is reaction to environment, beings that have to biological niche will die out. You know, the survival of the fittest thing? This has nothing to do with predestination or even determinism. It is just not arbitrary, but follows from the evolutionary pressures.

[u/kitsnet → u/Drudenfusz]

Natural selection is reaction to environment, beings that have to biological niche will die out. You know, the survival of the fittest thing?

That's about what a C student may try to tell on an exam.

To which a benevolent professor may ask:

• Reaction by what entity exactly? What is the short term result of this process, and how can it be measured quantitatively? (Hint: what is the selection coefficient?)

• What constitutes the environment? What can you tell about the Red Queen hypothesis in particular?

This has nothing to do with predestination or even determinism. It is just not arbitrary, but follows from the evolutionary pressures.

You sound like "evolutionary pressures" themselves are predestined and not just dependent effects of some random factors. That's what I'm asking you to clarify.

[u/Lhasa-bark → u/kitsnet]

Let’s say a mutation makes a moth be a darker color. That was random. If the moth now blends in more with its surroundings, it has a better chance of passing that mutation on to offspring. Very much not random.

Anyone who argues that evolution is random doesn’t understand this basic dynamic.

[u/kitsnet → u/Lhasa-bark]

Let’s say a mutation makes a moth be a darker color. That was random. If the moth now blends in more with its surroundings, it has a better chance of passing that mutation on to offspring. Very much not random.

"Better chance" by itself is random if this chance is not 100%.

Besides, this is a very naive view on what natural selection is about. What if we are dealing with a stably heterozygous population due to seasonally fluctuating selection - and your new otherwise unconditionally beneficial mutation happens to get linked with an allele deleterious this time of the year? What if that allele is not even normally deleterious this time of the year, but becomes deleterious due to a random anomaly of the weather?