> There is no heritable "diversity" trait.

That seems like too big a statement to be true. You're saying there is no structure which controls the variability of any phenotype? No gene that decides how much butterfly wing splotches vary? No gene that decides the difference between the shortest and longest legs in a family of mountain goats? No heritable diversity traits across the entirety of life?

Putting aside how unlikely that seems to me, if it was true... How could you possibly know such a thing? You can't prove a negative.

>No gene that decides how much butterfly wing splotches vary?

I think you're reading diversity to mean something different than the previous responses intended. Surely there are genes to control a phenotype. The issue under discussion is whether evolution selects specifically for genetic variation within a population (diversity of a population), without a more basic selection going on. My argument is that selection happens at the level of an individual and so it makes no sense to say that evolution selects for population diversity; there is no organism level selection mechanism that is the proxy for diversity at the population level, as there is in other purported population/species level selection events.

Are you saying you think selection happens only at the organism level?

I disagree with that, it happens at every level, from the continental down to the molecular.

Here's a question: are humans individuals, or are we colonies? What about an ant? Is it an organism, or is it an organ? I am not aware of a clear answer to these questions, so I would be excited to hear from you if you know of one.

>I disagree with that, it happens at every level, from the continental down to the molecular.

The problem is that evidence for this has been extremely hard to come by.

> I am not aware of a clear answer to these questions, so I would be excited to hear from you if you know of one.

Richard Dawkins' The Selfish Gene very elegantly explains the evolution of cooperative/altruistic behavior through analyzing the dynamics of gene selection. It's a great read for anyone interested in the finer details of evolution. The main takeaway is that cooperative behavior in organisms can be understood as genes encouraging their own proliferation by increasing the fitness of its copies in other organisms; a gene to help my brother is really a gene helping itself.

You seem to be contradicting yourself. On the one hand, you say molecules can't be selected for because they're not organisms. Then you say genes encourage their own proliferation, but genes aren't organisms, they're molecules.

You also never responded to the fact that humans are colonies, not single organisms, and yet I assume you believe humans are subject to selective pressure?

>you say molecules can't be selected for because they're not organisms

You misunderstand. My point about organisms was that selection happens at the level of organism, which was an imprecise way of saying organisms are what either procreates or dies, and so this is the level at which selection events occur. So any purported selection at a different level must have some organism-level proxy.

The statistics of what survives and what doesn't can still show effects happening at different levels. So when I speak of gene selection, I'm speaking from a statistical perspective. When I said that diversity isn't itself selected for, I meant that there is no strictly "diversity" selection happening at the level of organism.

>You also never responded to the fact that humans are colonies

Yes, humans are "colonies", meaning that we show cooperative behavior. But I don't see how that's relevant, at least in light of ways to understand the evolution of cooperative behavior at the gene level.

No, you are a colony. You contain multitudes.

Try to find a reputable scientist who will tell you there is an unambiguous distinction between an organism and an ecology. You won't find one, because there is no line. Nature doesn't care if you're a hive or a molecule.

How about viruses? Those aren't organisms, they can't reproduce at all. Just like an organ, or a gene, they need a host to replicate them.

Is it your opinion that viruses aren't subject to selective pressure?

>How about viruses? Those aren't organisms, they can't reproduce at all.

You seem to have trouble comprehending what's being said in context. Try to stop taking things out of context and then nitpicking them. If you came away from anything I've said thinking that I don't think viruses are subject to selective pressures, then you just didn't understand any of it.

>there is no heritable diversity trait.

What about mutation and recombination?

Mutation as in the random copy errors in DNA, aren't heritable in the sense that we're not inheriting the mechanism for mutation.

Recombination is a trait that increases diversity of a population, but its also a trait that increases the fitness of the individual organism's lineage as it allows greater diversity of genetic material and interactions between genes in its offspring. So there is an organism level effect that promotes the selection of recombination.

I originally granted that there are traits that can be seen to promote population diversity, but that they would be selected for by the increased fitness at the organism level, not because populations with more diversity better survive random black swan events.

Are you seriously arguing that mutation, as a mechanism, isn't heritable?

Spare me these rhetorical responses. If you have a point to make, just make it.

The only reason that your DNA has a copy error rate is because your parents DNA had a copy error rate.

Right, so we inherit the mechanism for replication, which has an intrinsic error rate. But the machinery isn't being selected for its ability to create random errors, that's just a byproduct.