Sign in

smishra677.bsky.social

@smishra677.bsky.social
42 followers 44 following 0 posts

PhD student at Hahn Lab IUB. --working on developing algorithms for problems in phylogenetic and population genetics Interest includes #MUFC

PostsRepliesMedia
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 15/09/2026
New paper with Trang Nguyen! Do you have only a single parent and offspring, but still want to calculate mutation rates? We've got the tool for you--OOPS github.com/TrangNg-Th/O... www.biorxiv.org/content/10.6...
biorxiv.org
Estimating de novo mutation rates using parent-offspring pairs
Existing pedigree approaches to identifying de novo mutations (DNMs) require at least two parents and a single offspring, limiting applicability. Here, we introduce OOPS (Only One Parent Sequencing), ...
03716
Reposted by @smishra677.bsky.social
Mark Hibbins, Great Lakes Swashbuckler @rejectresubmit.bsky.social · 14/08/2026
New review from me and @stepheniwright.bsky.social! We argue the time is ripe for a phylogenomic approach to the study of plant sex chromosomes: doi.org/10.32942/X2S...
doi.org
Plant sex chromosome evolution in the phylogenomic era
02814
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 02/06/2026
I’ll end there (there’s a bunch more in the paper), but please try out DAFT. And if you have any problems with the software, let us know! github.com/smishra677/D... 11/11
github.com
GitHub - smishra677/DAFT: Discordant attachment frequency tool
Discordant attachment frequency tool . Contribute to smishra677/DAFT development by creating an account on GitHub.
184
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 02/06/2026
Second, there can be “ghosted” introgression. Even though all species have been sampled, the act of introgression moving branch F leads to a signal of ghosted introgression between D and E (one additional square). We can quantify this, too. 10/n
141
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 02/06/2026
The tail of introgression also shows up in quartet-based tests. Below are the F-branch statistics for the same introgression event. The tail is represented by branches B, C, and (A,B) with recipient F (three additional squares). (The real event is highlighted in red.) 9/n
151
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 02/06/2026
First, introgression has a “tail” that generates discordant attachments due to ILS in the donor lineage. Below, even though species A is the donor, we see signals of introgression for many different branches being associated with recipient F. We can quantify this effect. 8/n
161
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 02/06/2026
Last but not least, the paper has a coalescent model of introgression for (somewhat) larger trees. While the math is simple, some very interesting things pop out that help explain the complex picture quartets give. Two of the most interesting: 7/n
141
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 02/06/2026
djiNNI is straightforward: given introgression between lineages at least two internal branches apart, it carries out a series of NNI moves to reconcile the tree. By keeping track of who is moved during this process, we can determine who the recipient of gene flow is. 6/n
142
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 02/06/2026
The paper (and DAFT) also contains a second method, djiNNI (pronounced as in the figure below). djiNNI can determine the direction of introgression using full gene trees. 5/n
141
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 02/06/2026
DAFT (Discordant Attachment Frequency Tool) carries out two kinds of tests to see whether any attachments appear more often than you’d expect. You just need to supply a species tree and a set of gene trees. The software is here: github.com/smishra677/D... 4/n
github.com
GitHub - smishra677/DAFT: Discordant attachment frequency tool
Discordant attachment frequency tool . Contribute to smishra677/DAFT development by creating an account on GitHub.
142
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 02/06/2026
Instead we use “discordant attachments” in full gene trees. Essentially, are two branches sister to one another in a bunch of gene trees when they shouldn’t be? For instance, the introgression event in the top panel here implies the discordant attachment shown in the bottom panel 3/n
141
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 02/06/2026
The motivation was to move away from quartet-based tests, especially when you’re studying a very large species tree. In such cases it can be hard to make sense of all the tests you have to carry out on many different quartets. e.g. from Suvorov et al. 2022 (a paper I really like!): 2/n
151
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 02/06/2026
Very happy to announce a big new paper from the lab, led by grad students @smishra677.bsky.social and Laia Pomar-Pallarès (in collaboration with @roblanfear.bsky.social). We introduce a new way to study introgression, with accompanying software (DAFT) 1/n 🧵 www.biorxiv.org/content/10.6...
biorxiv.org
49467
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 30/03/2026
New paper led by Yu Mo, with @psudmant.bsky.social Ever wonder how extreme genealogical discordance can help you to find the genetic basis for trait variation? Wonder no more! www.biorxiv.org/content/10.6...
A species tree and a cloudogram, both showing how much gene tree discordance there is in rockfishes
0255
Reposted by @smishra677.bsky.social
German Lagunas-Robles @g-lagunasrobles.bsky.social · 02/02/2026
Check out our paper on the neo-sex chromosomes in mountain pine beetle! We assembled THREE neo-Ys that are quite distinct and their corresponding neo-Xs .
196
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 23/01/2026
New paper with @smishra677.bsky.social! How many different trees can be generated by just one duplication event? It turns out A WHOLE LOT, if you consider the coalescent process. 1/ www.biorxiv.org/content/10.6...
biorxiv.org
24717
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 06/02/2025
Also, if you don't want to bother to read the preprint, you can just watch my talk on these results from this past year's Evolution meeting: 2/2 bsky.app/profile/3rdr...
0111
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 08/01/2026
Final version of paper with @smishra677.bsky.social now published in a wonderful issue of GENETICS! academic.oup.com/genetics/art...
academic.oup.com
Estimating recombination using only the allele frequency spectrum
Abstract. Standard methods for estimating the population recombination parameter, ρ, are dependent on sampling individual genotypes and calculating various
02616
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 07/01/2026
While our updated paper is fast approaching book-length, the results remain the same: our method (reconcILS) is still highly accurate. So if you want to reconcile gene trees and species trees--and you might have any ILS at all--this is the best method out there! www.biorxiv.org/content/10.1...
biorxiv.org
reconcILS: A gene tree-species tree reconciliation algorithm that allows for incomplete lineage sorting
Reconciliation algorithms infer the evolutionary history of individual gene trees given a species tree. Many reconciliation algorithms consider only duplication and loss events (and sometimes horizont...
04315
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 17/12/2025
Have you ever wondered: just how strong *is* the evidence for Muller's ratchet on mtDNA? Well, wonder no more! (Project led by Yu Mo, with @smishra677.bsky.social and @yadirapga.bsky.social) "No molecular evidence for Muller's ratchet in mitochondrial genomes" www.biorxiv.org/content/10.6...
biorxiv.org
No molecular evidence for Muller's ratchet in mitochondrial genomes
Muller's ratchet predicts that non-recombining genomes can accumulate deleterious mutations, though molecular evidence for it is rare. Previous studies have tried to detect ratchet-like behavior in mi...
39236
Reposted by @smishra677.bsky.social
bioRxiv Evolutionary Biology @biorxiv-evobio.bsky.social · 17/12/2025
No molecular evidence for Muller's ratchet in mitochondrial genomes www.biorxiv.org/content/10.64898/20…
097
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 07/10/2025
New preprint led by grad student, Yu Mo! We introduce new software to calculate evolutionary rates of quantitative characters in the presence of discordance 1/ www.biorxiv.org/content/10.1...
biorxiv.org
Estimating the rate of quantitative trait evolution in the presence of gene tree discordance by calculating likelihoods across trees
Quantitative traits provide insights into how phenotypes evolve across species. However, standard comparative methods often assume a single species tree and overlook the discordant gene tree histories...
12819
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 30/09/2025
Happy that our new paper is out, led by super-postbacc Daniel Rickert (now a PhD student at UNC). Also kind of excited to have my first TPB paper... 1/2 "Inconsistency of parsimony under the multispecies coalescent" www.sciencedirect.com/science/arti...
sciencedirect.com
Inconsistency of parsimony under the multispecies coalescent
While it is known that parsimony can be statistically inconsistent under certain models of evolution due to high levels of homoplasy, the consistency …
1121
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 01/09/2025
New paper led by @yadirapga.bsky.social! Opossums have babies at 6-months of age, but are still highly male-biased in their mutations academic.oup.com/genetics/adv...
academic.oup.com
Low mutation rate but high male-bias in the germline of a short-lived opossum
Abstract. Age and sex have been found to be important determinants of the mutation rate per generation in mammals, but the mechanisms underlying these fact
03118
Reposted by @smishra677.bsky.social
Genetics Society of America @genetics-gsa.bsky.social · 16/07/2025
In #GENETICS, @3rdreviewer.bsky.social‬ and @smishra677.bsky.social‬ show it is possible to estimate recombination solely using the allele frequency spectrum and provide a genealogical interpretation of the results, showing how #MachineLearning can provide insights into biology. buff.ly/emixz9W
0247
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 06/06/2025
Our paper (w/ @smishra677.bsky.social) is now out in Genetics! academic.oup.com/genetics/adv...
academic.oup.com
Estimating recombination using only the allele frequency spectrum
Abstract. Standard methods for estimating the population recombination parameter, ρ, are dependent on sampling individual genotypes and calculating various
06117
Reposted by @smishra677.bsky.social
Matthew Hahn @3rdreviewer.bsky.social · 06/02/2025
New paper with Sarthak Mishra! Maybe it will bring you some joy given all this (waves arms around). "Estimating recombination using only the allele frequency spectrum" 1/2 www.biorxiv.org/content/10.1...
biorxiv.org
Estimating recombination using only the allele frequency spectrum
Standard methods for estimating the population recombination parameter, rho, are dependent on sampling individual genotypes and calculating various types of disequilibria. However, recent machine lear...
37129