u/jnpha

Revealing How Speciation Works With Gene Flow (Farleigh et al. 2026)

Published yesterday, open access:

  • K. Farleigh, D.K. Highland, M.G. Alderman, Y. Francioli, S.R. Hirst, E.M. Faber, B.W. Perry, M.L. Holding, G. Castañeda-Gaytán, M. Borja, H. Franz-Chávez, C.L. Parkinson, J.L. Strickland, M.J. Margres, S.P. Mackessy, J.M. Meik, T.A. Castoe, & D.R. Schield, Evolution of genome-wide barriers to gene flow during complex speciation in rattlesnakes, Proc. Natl. Acad. Sci. U.S.A. 123 (21) e2609058123, https://doi.org/10.1073/pnas.2609058123 (2026).

 

Background

> Speciation with gene flow poses a central paradox: how do genome-wide barriers to gene exchange accumulate as recombination continually breaks down associations among selected loci? Although theory predicts that together recombination, selection, and genome structure shape reproductive isolation, empirical studies often report conflicting patterns, suggesting that these determinants change across the speciation continuum.

Methods

> Here we compare genomic landscapes of introgression across rattlesnake lineages spanning a range of divergence. We generated a chromosome-level reference genome for the Southwestern Speckled Rattlesnake (Crotalus pyrrhus) and analyzed whole genome data from 181 individuals across two species complexes with a history of gene flow upon secondary contact.

Results and discussion

> We show that reproductive isolation is highly polygenic and dynamically structured. At early divergence, introgression is most reduced in high recombination regions, consistent with increased efficacy of selection against gene flow at few large-effect loci. As divergence progresses, linked selection against gene flow dominates, generating a positive relationship between recombination and introgression expected to occur through the genome-wide coupling of polygenic barrier effects. Introgression landscapes also become increasingly correlated across species pairs as divergence increases due to repeated evolution of barriers in the same genomic regions. Here, we infer that the Z chromosome plays a prominent role in reproductive isolation, harboring a disproportionate number of barrier loci and showing reduced introgression even at early divergence.
Together, these results reveal how recombination, selection, and genome organization interact to shape speciation with gene flow upon secondary contact, reconciling empirical patterns with predictions of speciation theory.

 

Emphasis above mine showing that this is the same conclusion that I shared last month for a different paradox (Unraveling the lek paradox - why sexual selection does not deplete variation : evolution) - this gives more support to the evolutionary relevance of the infinitesimal model from quantitative genetics: traits being high polygenic or even omnigenic, with only a few large-effect genes.

See the linked post for a quick overview, and for a two-hour explainer (including the history and math), see Dr. Zach Hancock's The Lost Evolutionary Synthesis - YouTube (and the references therein; Barton 2022 is a very easy and fun read).

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u/jnpha — 8 hours ago
▲ 144 r/evolution

If Charles Darwin reappeared today, he might be surprised to learn that humans are descended from viruses as well as from apes; some 8% of human DNA represents fossil retroviral genomes

I've taken the title (which is playful) from Weiss (RIP) (2006); the diagrams are from Bannert (2006) and Meyer (2017) - all linked below.

BTW, today May 22nd is the 200th anniversary of the first voyage of HMS Beagle.


A really neat thing, besides serving as genetic markers, is that they allow for robust timing:

> During its residence in the germline, an ERV accumulates substitutions, and the two identical LTR sequences diverge at a rate approximating the neutral mutation rate of the host genome (with the possible exception of ERV loci evolving under selection). [...] If the ERV locus is shared by two or more species, a phylogenetic tree that incorporates both sets of LTR sequences (5′ and 3′) has a very predictable structure, allowing more robust time calculations ( Figure 3 ) (89, 95). The predicted topology has all the 5′ LTR orthologs of the ERV locus clustering together on one branch and the 3′ LTR orthologs clustering together on a separate branch [...].

-Johnson, Welkin E. "Endogenous retroviruses in the genomics era." Annual review of virology 2.1 (2015): 135-159.

 

Extras

 

  • Diagram sources:
    • Bannert, Norbert, and Reinhard Kurth. "The evolutionary dynamics of human endogenous retroviral families." Annu. Rev. Genomics Hum. Genet. 7.1 (2006): 149-173.
    • (top-left inset) Meyer, Thomas J., et al. "Endogenous retroviruses: with us and against us." Frontiers in chemistry 5 (2017): 250541.

 

For other markers, there's e.g. SINEs:

> [...] genetic markers called short interspersed elements (SINEs) offer strong evidence in support of both haplorhine and strepsirrhine monophyly. SINEs are short segments of DNA that insert into the genome at apparently random positions and are excellent phylogenetic markers with an extraordinarily low probability of convergent evolution (2). Because there are billions of potential insertion sites in any primate genome, the probability of a SINE inserting precisely in the same locus in two separate evolutionary lineages is “exceedingly minute, and for all practical purposes, can be ignored” (p. 151, ref. 3).

-Williams, Blythe A., Richard F. Kay, and E. Christopher Kirk. "New perspectives on anthropoid origins." Proceedings of the National Academy of Sciences 107.11 (2010): 4797-4804.

u/jnpha — 14 hours ago

Nails and ambush hunting - a specialization based on a phyloecological approach

> Primates of modern aspect (euprimates) are characterized by a suite of characteristics (e.g., convergent orbits, grasping hands and feet, reduced claws, and leaping), but the selective pressures responsible for the evolution of these euprimate characteristics have long remained controversial. Here, we used a molecular phyloecological approach to determine the diet of the common ancestor of living primates (CALP), and the results showed that the CALP had increased carnivory. Given the carnivory of the CALP, along with the general observation that orbital convergence is largely restricted to ambush predators, our study suggests that the euprimate characteristics could have been more specifically adapted for ambush predation. In particular, our behavior experiment further shows that nonclaw climbing can significantly reduce noises, which could benefit the ancestral euprimates’ stalking to ambush their prey in trees. Therefore, our study suggests that the distinctive euprimate characteristics may have evolved as their specialized adaptation for ambush predation in arboreal environments.

-Wu, Yonghua, et al. "Ambush predation and the origin of euprimates." Science Advances 8.37 (2022): eabn6248. https://doi.org/10.1126/sciadv.abn6248

 

The idea that nails evolved "for" gripping and climbing is a ridiculous just-so story; gestures at squirrels.

reddit.com
u/jnpha — 1 day ago

Deep Roots of an Arthropod Innovation

Published today, open access, in press:

  • Rodríguez-Aguilar, E.D., Martínez-Barnetche, J. & Rodríguez, M.H. Structure-guided analysis of divergent homologs unveils deep ancestry and arthropod specialization of the pacifastin family. Sci Rep (2026). https://doi.org/10.1038/s41598-026-52748-5

 

A delicious abstract:

Background

> The Pacifastin family has been widely regarded as an arthropod-specific innovation, functionally restricted to the regulation of innate immunity. Here, we challenge this paradigm using a structural phylogenomics approach that overcomes the sequence erosion characteristic of small disulfide-rich proteins.

Methods and results

> We identified a population of “cryptic” homologues comprising ~ 30% of the dataset—undetectable by sequence alone and demonstrated that the characteristic Pacifastin’s six-cysteine scaffold is not an arthropod invention but an ancient lineage whose evolutionary roots extend across major metazoan phyla, Fungi, and Bacteria. Structural and architectural profiling revealed two recurrent organizational modes: an ancestral class characterized by an N-terminal β-hairpin extension, glycine-rich and frequently embedded in multidomain, extracellular matrix–associated proteins, and a conventional, derived arthropod-restricted class characterized by modular simplification and predicted structural rigidity consistent with a soluble-effector function.

Discussion

> We propose a "Liberation and Structural Convergence" evolutionary model to explain this transition: the acquisition of proteolytic processing sites in inter-domain linkers is consistent with a mechanism by which arthropods may have released these domains from the matrix, while the concurrent structural convergence is consistent with adaptation to a soluble, circulating hemolymph environment. Further phylogenomic profiling of the reactive site revealed a functional shift from an ancestral inhibitory signature enriched in basic and charged residues to a derived arthropod-specific radiation toward hydrophobic residues. This transition suggests a broadening of target specificity toward chymotrypsin- and elastase-like proteases, consistent with the recruitment of these inhibitors into arthropod immune roles.

Summary

> Together, these results reposition pacifastins as an ancient protein lineage and illustrate how modularity, proteolytic processing, and biophysical constraints may have driven the transition from matrix-embedded regulatory scaffolds to systemic soluble effectors.

reddit.com
u/jnpha — 2 days ago

Answering Will Duffy's challenge to Richard Dawkins: the origin of the genetic code

Preempting the Why waste your time: the target audience is once again the 99%, and fans of biology. Also - selfishly(?) - trying to explain something helps one understand it better.
You can skip to the summary section, and read the sections later, if you wish.

The post is necessarily long (but made with love) for one main reason: my issue is not just the answer, but the challenge/question itself.

 

Duffy's challenge

Will Duffy, an hour and a half into his second lesson with Erika (six months ago), recounted his visit with a friend to Richard Dawkins' building at the University of Oxford (he wasn't in), with a printed challenge in hand (the friend made it), which a receptionist put in Dawkins' mailbox.

I uploaded a screen grab of that printout here.
It reads (I've removed Duffy's bold emphases except for one):

> Let's ignore all the wild complexity of the genetic code and try to give a Darwinian explanation for one of the simplest aspects of our DNA. Richard Dawkins, drawing on your lifetime of studying evolution, can you describe in as vague terms as you'd Like, how the 3-to-1 pattern could arise by a non-directed material process, such that three genetic letters code for one amino acid?

As Erika pointed out, this is a question about the origin of the genetic code, i.e. the origin of life, and she said she recalls Crick writing about that.
Indeed it was Crick, Woese, and a whole army, with a mountain of published research.
Because guess what? scientists love asking questions(!).

 

My gripes

Why pose that question to an evolutionary ethologist (animal behaviorist), beats me (not really; it's the YEC priming of "Atheists need evolution" and Dawkins is a prominent atheist, little they know atheism doesn't require a single scientific fact, and that the burden of proof is on them).
Of the points I'll try to make: they don't want to know the answer, despite the theatrics of the debate scene and going uninvited to a busy person's office with a googleable question.

Duffy preempted that by stating he just needs a "vague" answer, but IDists love nothing more than turning a simple answer into a straw man, so they can false-balance that with a quote mine of said straw man. (I have an example of Duffy doing the latter after the lesson on whales.)

 

Challenge breakdown

Again, not out of pedantry, as I've mentioned already:

> "Let's ignore all the wild complexity of the genetic code"

"Complexity" is the ID speak for design, so to burst that bubble (one of my pastimes here):

It took nine years from the discovery of the structure of DNA to decipher one codon, and 13 years in total to decipher all of them.
All the logical attempts, mostly by eager physicists, failed spectacularly, because the code has no logic behind the codon mapping (a fact that I'll explain). I think this should matter to the IDists:

No Logic Behind The Mapping.
No Logic Behind The Mapping.
(I'll mention below something about plants, when you get to it, revisit this)

 

> "try to give a Darwinian explanation ... a non-directed material process"

This nicely illustrates his IDist anti-materialism and very likely confusion given that tautology. Darwinism (in its academic sense), i.e. the process, is universal in the sense that to a Darwinist (in its respectable sense) it has no trouble at all accounting for the origin of the genetic code, even without knowing any of the details.

There is a reason engineering relies on that blind process to solve otherwise unsolvable problems. (See this post by u/gitgud_x and the one linked therein by u/theosib.)
Heck, Universal Darwinism was a Dawkins paper published in 1983.
And it's the same reason Dennett titled his 1995 book, Darwin's Dangerous Idea.

It's a process that not only solves the aforementioned engineering problems, it demonstrates that mind needn't come first. (The relevance of this to the "debate" is covered in the linked post just above.)

 

> "one of the simplest aspects of our DNA"

It's not the simplest aspect, unless - again - one is thinking like an IDist. Solving that one, solves all of it, bottom-up.

 

> "3-to-1 pattern could arise ... such that three genetic letters code for one amino acid"

Again with the tautology.
Duffy (or the friend) knows enough biology to know said pattern, and doesn't know the word "codon"? and hence codon mapping?
This feels like the intended audience wasn't Richard Dawkins(?).

The main point of this section was to highlight the erroneous, misleading and presuppositional framing; and the laziness to go on Google Scholar, or schedule a meeting with an appropriate expert - but no, best pretend it's unsolveable because personal incredulity.

 

Another IDist's "challenge"

The same comes up regularly here - here's one such recent example:

> I don't think AIG (or someone like Stephen Meyer) would argue that random mutation is unable to create a very small amount of information, like the 4 letter word in your example. Especially when you chose the initial word in the first place. What they (and I) would argue is that random mutation won't generate the sequence needed for even a small gene, much less all of the information needed to produce the proteins and rna that perform the transcription and translation processes. Without those processes, the information encoded in DNA is useless.

Quick breakdown:

> "What they (and I) would argue is that random mutation won't generate the sequence needed for even a small gene"

Randomly-generated sequences have literally disproved that (btw), but then again that comment was left by someone who once (hopefully that has changed) refused the role of stochasticity in chemistry(!), let alone that specificity isn't on/off.
Now take a closer look at:

> "the information needed to produce the proteins and rna that perform the transcription and translation processes. Without those processes, the information encoded in DNA is useless."

Not only is it self-contradictory, the author of that comment - if only they'd remove the intelligence blindfolds - answered their own question.
And like Duffy, I still wonder (not really as I've explained) where is the difficulty in searching for, ideally, books on Google or Google Scholar.
I, too, am curious about the world, I've asked the same question, and I've found answers.

 


The answer

- Let's meet the cast

  • tRNAs (transfer RNA)
    they "carry" (I'll dispense with the scare quotes moving forward) the activated amino acids
  • ribosomal proteins
    they come together to form the ribosome (part-RNA too) that makes the proteins
  • AARSs (aminoacyl-tRNA synthetases)
    they activate the amino acids and attach them to the tRNAs

 

- Present setting

An RNA enzyme (polymerase) reads the DNA and makes an mRNA or tRNA.

The ribosome (made of the aforementioned ribosomal proteins and some RNA) reads holds said mRNA, and matches waits for the tRNA ferrying the right amino acid to bump into it (stochastic bumping, verifiably so).

And earlier the AARSs (one for each amino acid) activate and attach said amino acids to the tRNAs.

 

- Prebiotic setting

Here, Jacques Ninio's (1982) analogy for molecular evolution will be useful: a hotel's passkey (which opens all the doors) is less complex than the room keys, because it is less specific, and it is the same case here: an increase in specificity, due to and via selection - Darwinian evolution 101.
(fun fact! direct evidence of this at the single-molecule kinetics level has been achieved)

But selection for what? That's the Darwinian answer Duffy wants.
Carl Woese pointed out selection for what in 1965, 61 years ago. (recall what I said about scientists, and the refusal to google)

  • Selection for:
    • Reduction in translation error
    • Reduction in code ambiguity

Starting from statistical RNAs and proteins, a reduction in translation error means a selection for an increase in ribosomal proteins, for an increased specificity, with the tRNA coevolving (1859 Darwinism applied to a molecular - still "ecological" - setting). This selection for specificity (and redundancy; in molecular speak: codon degeneracy) also explains why the codon is 3 letters long (has to do with the biophysics error rate of each position with the second being the most stable - needs to be flanked, in other words).

But because the code (codon mapping) was still ambiguous, this alone does not help.

Enter the simultaneous selection for ambiguity reduction, which is a selection for an increase in the AARS proteins and the secondary amino acids.
Back and forth, back and forth, until it has settled into what has been termed a frozen accident - very optimized but an accident. (recall what I've mentioned earlier: the codon mapping is not logical)

-

Can this be bootstrapped from random sequences? (That's why I mentioned that earlier.) With an increase in specificity? (The passkey.) With clues left behind? (A mountain of research.)
So Yes to all. As an example of a clue: remove selection from the translation, and the tRNAs evolve away and the mapping changes (e.g. a very recent study on plants that become parasites of other plants; Ceriotti et al 2026, which I shared on r /evo). An older clue: the genetic code is not universal (only nearly so).

There you go, and a couple of billion years later, and Bob (the extinct hominoid) is our uncle.

 

Example research area

AARSs, annoyingly, come in two classes.
Two very different classes, which poses a problem. Because assuming two separate origins would leave the above genetic code origin in a pickle.

What did I say about scientists, as opposed to IDists?
Enter the Rodin-Ohno hypothesis; they "proposed that the two superfamilies descended from opposite strands of the same ancestral gene", based on tantalizing evidence.
Initially it was thought to be unfalsifiable, but as it turns out, that is not the case; experimental attempts at falsification failed, and Bayesian analyses support it.

As a taste:

  • 1995
    Rodin, Sergei N., and Susumu Ohno. "Two types of aminoacyl-tRNA synthetases could be originally encoded by complementary strands of the same nucleic acid." Origins of Life and Evolution of the Biosphere 25.6 (1995): 565-589. https://doi.org/10.1007/bf01582025

  • 2014
    Carter Jr, Charles W., et al. "The Rodin-Ohno hypothesis that two enzyme superfamilies descended from one ancestral gene: an unlikely scenario for the origins of translation that will not be dismissed." Biology Direct 9.1 (2014): 11. https://doi.org/10.1186/1745-6150-9-11

  • 2025
    Wang, Minglei, M. Fayez Aziz, and Gustavo Caetano-Anollés. "Tracing the origin of the genetic code and thermostability to dipeptide sequences in proteomes." Journal of Molecular Biology (2025): 169396. https://doi.org/10.1016/j.jmb.2025.169396

and

What do IDists do in such a case?
What they always do: move the goalpost (pretend the question, "How could it have happened?" wasn't answered) to something else, e.g. But you didn't see it (because when in doubt: Last Thursdayism), or the equally braindead false Thomistic analogy: But the experiments needed intelligence.

 

Recap (all qualified above)

  • TL;DR: Will Duffy's requested an answer in vague terms, and so:
    (barring trickster deities and Last Thursdayism)
    The genetic code and "3-to-1" evolved via an increase in specificity starting from statistical RNAs and proteins in response to the dual selection on error and ambiguity reduction, supported by the very attributes and heterogeneity of the "machinery" of the cell across life.

  • IDists pretend scientists don't ask or ignore questions

  • IDists pretend to have unanswer_able_ questions, therefore... <shrugs>

  • IDists pretend to seek answers

  • IDists pretend Darwinism hadn't already solved the no-mind-first problem, and so the design presupposition is present in their questions

  • IDists need to read this from 1859:

It is so easy to hide our ignorance under such expressions as the “plan of creation,” “unity of design,” etc., and to think that we give an explanation when we only restate a fact.
-Darwin, Charles

Finding a multi-part system, and restating the fact as "design", is, as noted by Darwin above and Francis Bacon centuries earlier, is not will never be an explanation.
Between their bogeyman "materialistic science", and their ID, only one of those actually answers questions.

 

Over to the pros here, and I hope it wasn't too boring.

 

^(edits: my memory failed me at the details of the visit, so revised that, plus one typo fix, the rest of the blemishes are left intact)

u/jnpha — 3 days ago

An old, unsolved problem ... Maynard Smith’s analogy, realized: Common ancestry constrains evolutionary percolation through protein space

  • PNAS Commentary:
    S.N. Manivannan, & C.B. Ogbunugafor, Maynard Smith’s analogy, realized: Common ancestry constrains evolutionary percolation through protein space, Proc. Natl. Acad. Sci. U.S.A. 123 (21) e2610113123, https://doi.org/10.1073/pnas.2610113123 (2026).

  • The study:
    L.H. Isakova, E. Streltsova, O.O. Bochkareva, P.K. Vlasov, & F.A. Kondrashov, Descent from a common ancestor restricts exploration of protein sequence space, Proc. Natl. Acad. Sci. U.S.A. 123 (14) e2532018123, https://doi.org/10.1073/pnas.2532018123 (2026). (open access)

 

From the commentary:

> In a new study published in PNAS, Isakova et al. address an old, unsolved problem in evolutionary biology: of all the protein sequences that could plausibly function in living cells, how many has evolution explored (1)? The answer, drawn from an analysis of thousands of protein families across vertebrates and bacteria, revisits this puzzle. The region of functional sequence space occupied by natural proteins is orders of magnitude smaller than models of protein evolution predict. Why is this so? What is the dominant constraint on how far evolution has percolated through the space of possible proteins? It turns out to be neither the difficulty of traversing the embedded fitness landscape, nor the efficiency of natural selection, but descent from a single common ancestor. The leash of shared origin, the authors demonstrate, matters more than any property of the landscape, or force of evolution.

reddit.com
u/jnpha — 4 days ago

Wilson and Sarich (1969): The birth of a molecular evolution research paradigm

u/jnpha — 4 days ago

Puente-Lelievre et al. (2025) - using homology searches, Bayesian phylogenetics, ancestral sequence reconstruction, AlphaFold structural predictions, and experimental validation - find that the flagellar stator motor complex evolved from an ancestral ion transporter

This is the change of function (Darwin 1859) or exaptation as the theory of evolution says when it comes to complex multi-part systems; open access educational article: The Evolution of Complex Organs | Evolution: Education and Outreach | Springer Nature Link.

u/jnpha — 6 days ago

On the "most important debate in the history of Genetic Entropy"

6 weeks ago:

We are 6 weeks out from the most important debate in the history of Genetic Entropy : DebateEvolution

I watched the debate, start to finish. And it was my first experience with the debate channel "SFT".
And I was pleased with the moderation and well-timed segments (credit where credit is due).

Of course I have many gripes, mostly to do with the lack of real-world data from Mr. Price, his use of AI to create a comic of Dr. Zach (the theatrics of the debate! - it may score points on the creationist side, but it was, at best, very childish), and how he basically kept talking past the points Dr. Zach made, but I was glad Dr. Zach pointed that out - namely: zero response to the models that actually match reality, and the food we eat.

 

Now, a point that stood out to me that I'd like to share is when Mr. Price said:

> I will say it is a pet peeve of mine. Evolutionists constantly accuse creationists of quote mining. When you make that accusation, what you're essentially saying is that I took a quote out of context and I misrepresented the intended meaning of the author. So, if you're making a claim like that, you've got to back it up. You can't just throw it out and say I was quote mining. And in fact, I would also answer the claim that the quotes that I had were unfortunately - it's quite common in the literature for people to speak in a shorthand way and just say neutral [theory]. But if you read the literature closely, it is well understood that no mutations are strictly neutral. All the way back to the 70s. Kimura's 1979 paper had zero strictly neutrals and that is confirmed by the Walker and Keightley paper that my opponent cited in his published work. So no, when these scientists say neutral, they don't mean strictly neutral. They mean effectively neutral.

 

To take two excerpts from that for my commentary:

  • RE:

> unfortunately - it's quite common in the literature for people to speak in a shorthand

It's because they are addressing their fellow subject-matter experts. If they weren't, each paper would be book length, defeating the purpose.

  • And RE:

> when these scientists say neutral, they don't mean strictly neutral. They mean effectively neutral.

This is what philosophers do - they keep guessing what X or Y philosopher said and meant.
So on the one hand: a subject-matter expert (with real-world data); and on the other: a layperson who is treating a model (a spherical cow) as an edict.

 

On that point, here's from an academic review on 50 years of work on neutral theory:

> ... we have reached this peculiar situation where the analysis of amino acid substitution rates has both led to a clear rejection of a major claim of the neutral theory—that most observable changes are neutral—and at the same time indisputably demonstrated the importance of drift in protein evolution. > > Of note, this research was sustained by a remarkable effort to develop models of sequence evolution and statistical methods of substitution rate estimation (e.g. Thorne et al. 1998; Yang and Nielsen 2008; Lartillot and Poujol 2011), which, in turn, opened exciting opportunities such as, among other things, the characterization of the distribution of fitness effects of mutations (Castellano et al. 2019), the reconstruction of ancestral Ne and ancestral traits (Brevet and Lartillot 2021), and the connection between the biochemistry and the evolution of amino acids and proteins (Glaser et al. 2003; Goldstein 2013).
https://doi.org/10.1093/gbe/evae003

 

This is what the "debate" should have been about; e.g. whether drift can account for evolution at the molecular level - the evolution of the so-called molecular "machines". And the answer is yes.

Also I'm yet to square the circle that is design and genetic entropy - as in: Is life "intelligently" designed to deteriorate? I'm betting it's one of those, Who knows his wisdom kind of topics, while ignoring the internal inconsistency with the whole "design" thing.

N.B. needless to say re all the above: I'm commenting on the argument, NOT the person.

u/jnpha — 7 days ago

[Historical lit. review] Sibley & Ahlquist's 1984 resolution of the hominoid phylogeny

Initially I wanted to post something about Fitch & Margoliash's (1967) first application of statistical phylogenetics to a molecule, cytochrome c.
But One Rabbit Hole Later, I present Sibley & Ahlquist (1984).

  • On the left:
    The situation at the time (just 42 years ago); up until then the "problem of the trichotomy of man, chimpanzee and gorilla" was unresolved (TIL!).

  • On the right:
    The resolution and the remarkably-accurate(??)* dating; another "TIL" (besides the recency of the resolution) was about the DNA clock, as opposed to the molecular clock.
    (*more + excerpts in the comments)

Source:
- Sibley, Charles G., and Jon E. Ahlquist. "The phylogeny of the hominoid primates, as indicated by DNA-DNA hybridization." Journal of molecular evolution 20.1 (1984): 2-15. https://link.springer.com/article/10.1007/BF02101980

u/jnpha — 7 days ago

Beyond Genomes: Functional Signatures Reveal Evolutionary Patterns Across the Tree of Life (Muñoz-Mérida & Muñoz-Pajares 2026)

> Protein function evolution provides a powerful lens to uncover biological complexity. Here, we introduce the concept of the pan-functionome—the full set of protein functions encoded by the proteome of individuals belonging to a taxonomic group—and explore its evolutionary implications. By analyzing over 1,000 annotated proteomes across major branches of life, we identify systematic differences in functional composition that reflect deep evolutionary patterns. The number of biological processes per protein increases non-linearly over time, with functional diversification rather than protein expansion driving organismal complexity. Distinct taxonomic divisions invest differently in biological processes, highlighting signatures of multicellularity, metabolism, and stress response. Phylogenetic analyses suggest that the evolution of protein functions follows a non-neutral model. Furthermore, functional profiles allow robust taxonomic classification and reveal unique adaptations in individual organisms. Our findings suggest that the functionome provides a complementary perspective on evolution, with potential applications in taxonomy, evolutionary biology, and comparative genomics.

  • A Muñoz-Mérida, A J Muñoz-Pajares, Beyond Genomes: Functional Signatures Reveal Evolutionary Patterns Across the Tree of Life, Molecular Biology and Evolution, 2026;, msag121, https://doi.org/10.1093/molbev/msag121

(accepted yesterday; in press; open access)

u/jnpha — 8 days ago

The 1-Domain Hypothesis (based in part on discoveries related to membrane coat proteins, and of phagocytosis-related processes in Planctomycetes)

> The relationship between the three domains of life—Archaea, Bacteria, and Eukarya—is one of Biology’s greatest mysteries. Current favored models imply two ancestral domains, Bacteria and Archaea, with eukaryotes originating within Archaea. This type of models has been supported by the recent description of the Asgardarchaeota, the closest prokaryotic relatives of eukaryotes.
However, there are many problems associated with any scenarios implying that eukaryotes originated from within the Archaea, including genome mosaicism, phylogenies, the cellular organization of the Archaea, and their ancestral character. By contrast, all models of eukaryogenesis fail to consider two relevant discoveries: the detection of membrane coat proteins, and of phagocytosis-related processes in Planctomycetes, which are among the bacteria with the most developed endomembrane system.

  • Devos, Damien P. "Reconciling asgardarchaeota phylogenetic proximity to eukaryotes and planctomycetes cellular features in the evolution of life." Molecular Biology and Evolution 38.9 (2021): 3531-3542.
    https://doi.org/10.1093/molbev/msab186 (open access)

Those who research this area, share your thoughts!

u/jnpha — 9 days ago

One Graph Attempts to Connect Every Object in the Universe (Steward & Hedman 2026)

This was a fun read: One Graph Attempts To Connect Every Object In The Universe - Universe Today

Based on:
- Steward, Gabriel M., and Matthew Hedman. "The Cohesive Object Sequence: The Mass–Density Distribution of Astronomical Objects from Asteroids to Stars." Publications of the Astronomical Society of the Pacific 138.4 (2026): 041001. https://arxiv.org/abs/2604.06029

u/jnpha — 10 days ago

Evolutionary History of Mammalian Ancestor Chromosomes (Damas et al 2022)

The images in order:

  1. Damas et al 2022
    The synteny diagram shows a reconstruction of the chromosomal rearrangements Mammalia has went through (n.b. these are not single generation events); a close to home one is the crash fusion leading to our chromosome 2 (bottom of the image);
  2. Schematic of said chr2 fusion from Vorob'eva et al 2006;
  3. 20 Years Later
    Details galore of said fusion from Yang et al 2026;
  4. I'll come back to that (Schultz et al 2023) in the comments.

(comments section for more)

u/jnpha — 10 days ago

Human/Chimp Difference - Nucleotide Visualization of Whole Genomes

Human-Chimp chromosome 19 alignment
A colored pixel in the difference columns is a single letter change. For the two big differences shown above (areas annotated A and E on the left):

> (A) Chimpanzee has a ∼1700 bp sequence not present in Human, (B,D) followed by an inversion, (E) which ends at a AAAC tandem repeat where Human has twice as many copies.

Source: Fig. 3 in:

  • Seaman, Josiah, and Richard JA Buggs. "FluentDNA: Nucleotide visualization of whole genomes, annotations, and alignments." Frontiers in Genetics 11 (2020): 292.
    https://doi.org/10.3389/fgene.2020.00292

1-hour explanation from last year by Erika (Gutsick Gibbon): Okay How Similar are Humans and Chimps Genetically Now That We Have Full Genomes? - YouTube.

u/jnpha — 11 days ago
▲ 167 r/evolution

Our evolutionary history

Sources:

The first diagram is based on the second after incorporating the latest findings as of around 2017 (they are listed in the Wikimedia link). And doubtless the phylogeny is even clearer now; this is where your insights come in :)

u/jnpha — 12 days ago

Evo-devo Gene Toolkit

Image source:

  • Stefanie D. Hueber, Georg F. Weiller, Michael A. Djordjevic, Tancred Frickey, CC BY 4.0, via Wikimedia Commons

Quick background:

> [Hox genes] are general purpose in the sense that they are similar in many organisms; it doesn’t matter if it’s a mouse’s head or a fly’s head that is being built, the same gene directs the process. Small changes in such powerful regulatory genes, or changes in the genes turned on by them, could represent a major source of evolutionary change.
- berkeley.edu's Hox genes

Some links:

u/jnpha — 13 days ago

The silliness of "common design" and this or that "irreducibly complex" molecule

This is a short one for a change, and what I find as the shortest rebuttal.
And since Darwin lives rent free in their heads, I'll start there:

> It is so easy to hide our ignorance under such expressions as the “plan of creation,” “unity of design,” etc., and to think that we give an explanation when we only restate a fact.

(emphasis mine)
- Darwin, Origin, 1st ed., 1859.

 

Oh, look; he had considered it.
Restating facts is never an explanation. Imagine an engineer tasked with reverse engineering a competitor's device, and all they could state is, "It has interdependent components; I infer a designer made it". Or as Dr. Padian remarked during Dover, no one has gotten a Nobel for stating what an eight-year-old knows - yes! it has parts, and we've worked out the how.

This is how silly both arguments are.

 

And given the purpose of this sub, some links for the 99%:

 

(also I'm curious to see if any will attempt to back up ID's rhetoric instead of deflecting)

u/jnpha — 13 days ago

Spindle diagrams are based on the extensive fossil record, with the number of families as a measure of diversity (width of each lineage) at each moment in time (y-axis)

Sources:

  • Petter Bøckman, Public domain, via Wikimedia Commons
  • Benton, Michael J., and David AT Harper. Introduction to paleobiology and the fossil record. John Wiley & Sons, 2020.

(for why I love them, see the comments)

u/jnpha — 14 days ago