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David Pollock

@genomesevolve.bsky.social

550 followers 680 following 380 posts

Evolutionary and Mathematical Biology, sequence structure and function, genomes evolve, statistical theory and knowledge, empirical-theoretical interface, communication of evolutionary genetics, collaboratives, the mind-body problem, humanism

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David Pollock @genomesevolve.bsky.social · 10h

Perhaps this is where the law of large numbers you are looking for comes in? If the population is large, and the allele is moderately frequent, there will be a modestly large number of alleles with average effect to average over in the population?

David Pollock @genomesevolve.bsky.social · 10h

Hmm, it seems you are now focused on conditions for introduction of a new allele. In most cases of moderate selection, the immediate probabilities are going to be more strongly affected by drift, yes, so the mechanism of selection doesn't matter much. Better to focus on slightly higher frequencies.

David Pollock @genomesevolve.bsky.social · 10h

Necessary benefit would be less if you knew when to produce for carrier or not, but equations still balance at some point. But again, let me know if I am missing something, which is entirely possible.

David Pollock @genomesevolve.bsky.social · 10h

Simple version of your model, let's go with constant clutch size 2. Cost of low frequency new allele is x. 50% of time allele is in sib (so reciprocal benefit). So benefit to receive only received half the time, cost all the time, so that determines what benefit must be.

David Pollock @genomesevolve.bsky.social · 10h

Let's pull back a moment and ask whether your line of argument would apply to any selected gene. If an allele is positively selected randomly in only 1/10 generations, it still has an average effect that determines its benefit.

David Pollock @genomesevolve.bsky.social · 10h

The next step is to berate your friends for not telling you earlier

David Pollock @genomesevolve.bsky.social · 10h

I may be missing something, but it seems to me that the models of identifying siblings to preferentially receive benefits works for the same reason structure models work. Organism doesn't need to "know" or be right about who carries gene, just average benefit is higher than cost.

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David Pollock @genomesevolve.bsky.social · 17h

typo, it is type IV secretion system

David Pollock @genomesevolve.bsky.social · 17h

So you're saying that this was not the obvious solution?

type I secretion system molecular graphic that is incredibly complicated but also incredibly beautiful

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David Pollock @genomesevolve.bsky.social · 17h

That is a hard call, but probably the right one (if one is able).

David Pollock @genomesevolve.bsky.social · 1d

If it were easy it wouldn't be so much fun!

David Pollock @genomesevolve.bsky.social · 1d

I agree with the obvious wild variety of emergent phenomena, but I would say that our particularly useful theory of emergence is called "evolution" @dadrummond.art @clauswilke.com

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Reposted by David Pollock

Jeffrey Ross-Ibarra @jrossibarra.bsky.social · 1d

PEQG website live! genetics-gsa.org/peqg-2026/

Homepage - 2026 Population, Evolutionary, and Quantitative Genetics Conference

Visit our website to learn more.

genetics-gsa.org

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David Pollock @genomesevolve.bsky.social · 2d

I've had complaints about using mathematical equations in talks ("nobody wants those"). But I never tried explaining them using rhyming couplets, so maybe that was the problem.

David Pollock @genomesevolve.bsky.social · 2d

One of the grant comments I am proudest of is someone's complaint that too many of my descriptions were written in prose. Yes, that is what I was trying for. Clarity, not muck (ie, not obfuscation, in more obfuscatory language)

Ellinor Alseth @ellinoralseth.bsky.social · 3d

Obsessed with this Journal of Immaterial Science article 🔥

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David Pollock @genomesevolve.bsky.social · 2d

More complex, therefore more evolved. The new onion.

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Reposted by David Pollock

Cameron Thrash @jcamthrash.bsky.social · 2d

A cartoonist's review of AI art - The Oatmeal theoatmeal.com/comics/ai_ar...

A cartoonist's review of AI art - The Oatmeal

This is a comic about AI art.

theoatmeal.com

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David Pollock @genomesevolve.bsky.social · 2d

Yes.

Reposted by David Pollock

Tami Lieberman @contaminatedsci.bsky.social · 3d

We've made a related but different claim in bacteria:
elifesciences.org/articles/93146

Reversions mask the contribution of adaptive evolution in microbiomes

The timescale dependence of dN/dS in bacteria is better explained by adaptive than purifying dynamics, suggesting comparative genomics can underestimate past adaptation.

elifesciences.org

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David Pollock @genomesevolve.bsky.social · 3d

Another paper to go over more thoroughly. Have you tried running your large population with frequency dependent selection? (apologies if already there in the paper and I just missed it)

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David Pollock @genomesevolve.bsky.social · 3d

At top of reading list

David Enard @denard.bsky.social · 3d

We think this is definitely the case given what we see with virus-driven adaptation in host proteins that interact with viruses. The latter drive very strong selection. We do find signatures of compensatory protein stability evolution:
www.biorxiv.org/content/10.1...

Stability evolution as a major mechanism of human protein adaptation in response to viruses

Pathogens were a major driver of genetic adaptation during human evolution. Viruses in particular were a dominant driver of adaptation in the thousands of proteins that physically interact with viruse...

www.biorxiv.org

David Pollock @genomesevolve.bsky.social · 3d

No, we will not release the Western Blot files, and please stop talking about them.

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David Pollock @genomesevolve.bsky.social · 3d

On the other hand, strong adaptive is the best case for pairwise compensation through tight interaction. And that syncs with longstanding knowledge about tight compensatory relationships in eg core of proteins. They just don't happen without strong selection on first change.

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David Pollock @genomesevolve.bsky.social · 3d

Ah, this is interesting. I do think adaptive compensatory change is often achievable in multiple ways, making it much more difficult to detect. Detectable en masse when looking at intramolecular coevolution, clear evidence for it but not so much pairwise.

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Reposted by David Pollock

Bookshop.org @bookshop.org · 3d

Can’t decide what to buy on Prime Day?

Try: absolutely nothing, and then go support indie bookstores instead 📚

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