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Nicolas Bierne

@couplingdmi

CNRS researcher at @isemevol.bsky.social Montpellier Population Genetics, Evolution, Marine Biology, Transmissible Cancers #PopGen #Hybridization #Introgression #MarEvol #Transcan #MusselsAreCool

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17.12.2023
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Latest posts by Nicolas Bierne @couplingdmi

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On the expansion and evolution of a master’s project Academics often lament that hardly any master’s projects – even the best ones – get published. The student moves on. Other research takes priority. No one has time to do the final analyses. Here I tel...

Academics often lament that hardly any master’s projects get published. The student moves on. Other research takes priority. No one has time to do the final analyses. Here I tell how one master’s project was, through persistent teamwork, finally carried over the finish line: go.nature.com/4aKs7N3

04.03.2026 14:24 👍 24 🔁 9 💬 1 📌 1

Un poste MCF en génomique évolutive / écologie moléculaire à ECOBIOP - Université de Pau #PopGen 👇
urlr.me/rVQmN6

05.03.2026 14:21 👍 2 🔁 3 💬 0 📌 0

April Fools’ Day is coming early this year, but really, any day is a good day to poke fun at the system.
Well done @russcd.bsky.social

03.03.2026 17:40 👍 2 🔁 3 💬 0 📌 0

Un poste MCF en évolution de la biodiversité marine à l'Université de La Réunion UMR Entropie #MarEvol 👇
www.univ-reunion.fr/wp-content/u...

03.03.2026 14:47 👍 0 🔁 2 💬 0 📌 0

We are offering a fully funded two-year postdoctoral position focused on sex chromosome evolution and speciation in the *Jaera albifrons* species complex. Please find the advertisement attached. We welcome applications from interested candidates. Join us :-)

03.03.2026 09:44 👍 16 🔁 16 💬 1 📌 0
David Alexander Marques (1984–2026) - Nature Ecology & Evolution Speciation genomics researcher, author of the combinatorial theory of speciation and passionate birder

David Marques was an amazing speciation genomics researcher, a passionate birder, and a wonderful friend, husband, and father. May he rest in peace. www.nature.com/articles/s41...

02.03.2026 13:44 👍 55 🔁 29 💬 2 📌 2
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A Beginner's Guide to Structural Variants in Eco‐Evolutionary Population Genomics Whole-genome sequencing (WGS) has greatly expanded researchers' ability to study structural variants (SVs), that is, the variation in the presence, number, orientation or position of a DNA sequence. ....

New out: A Beginner’s Guide to Structural Variants in Eco-Evolutionary Population Genomics.

We outline how to detect and analyse SVs, discuss key challenges, and provide a practical framework for population-level studies

A resource for students entering SV research.
doi.org/10.1111/mec....

25.02.2026 00:34 👍 7 🔁 3 💬 0 📌 0
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Post doc position in Evolutionary biology and bioinformatics - work environment: This postdoctoral position will be supervised by Aline Muyle and hosted at the Institute of Evolutionary Sciences of Montpellier (ISEM), within the CHANGE department and the Plant ...

I am hiring a Postdoc (18 months contract in Montpellier, France) to study how polyploidy affects sex chromosomes in the plant Silene latifolia, using bioinformatic analyses of RNA-seq and DNA-seq data. Deadline for applications March 24th. euraxess.ec.europa.eu/jobs/412961

24.02.2026 15:57 👍 18 🔁 36 💬 0 📌 0

New work from the lab: Miles @milesroberts.bsky.social tried out machine learning to estimate sweep times to fixation and (spoilers) it didn't really help www.biorxiv.org/content/10.6... As always, we'd appreciate any feedback!

18.02.2026 13:59 👍 22 🔁 10 💬 0 📌 0

Results of this work suggest 1- that episodic windows of adaptive introgression can generate new admixed lineages and 2- repeatability arises from multi-genic positive selection favouring the same introgressed variants borrowed from semi-isolated related species.

24.02.2026 10:52 👍 1 🔁 0 💬 0 📌 0

Here we found three admixed lineages, each derived from three parental species. 3-way admixture !
We show that repeatability is not primarily driven by systematic depletion of minor ancestry. It is instead shaped by recurrent enrichment of the same shared minor-parent ancestry peaks.

24.02.2026 10:52 👍 2 🔁 0 💬 1 📌 0

With only two parents, we lack one degree of freedom. When we observe repeatable patterns of ancestry across hybrid zones, we can map chromosome regions affected by selection. However, we cannot determine the direction of selection. Is foreign ancestry purged or favoured?

24.02.2026 10:52 👍 1 🔁 0 💬 1 📌 0

A more technical point, but an even more fascinating one.
In hybridization genomics, we usually scan admixed genomes for:
• minor ancestry deserts → candidate barrier loci
• minor ancestry peaks → adaptive introgression

But we almost always study 2-parent admixture.

24.02.2026 10:52 👍 1 🔁 0 💬 1 📌 0

We often think of hybridisation as occurring after long periods of allopatry. In this case, however, isolation is maintained in sympatry, with species barriers suddenly breaking down at a range limit.

24.02.2026 10:52 👍 1 🔁 0 💬 1 📌 0

Cryptic coral species can remain reproductively isolated in the same reefs with only minimal gene exchange for over 300 KY ... and then suddenly interbreed at the edge of their range.
For a fan of post-glacial secondary contacts as I am, this was a real surprise.

24.02.2026 10:52 👍 1 🔁 0 💬 1 📌 0

A huge thank you to Iva and Cynthia @seaprof.bsky.social and the all Riginos lab for inviting me to make a modest contribution to this study.
My first coral paper 🌊🪸 🎉 A dream come true 😊.

I really encourage you to read it #MustRead

Two major take-home messages for hybridization genomics 👇

24.02.2026 10:52 👍 7 🔁 2 💬 1 📌 0
Table coral

Table coral

Three-way hybridization of table corals in the Acropora hyacinthus group from the southern Great Barrier Reef results in parallel adaptive introgression. Check out our new preprint: doi.org/10.64898/202...

#CoralSky #MarEvol #coral #popgen #consgen #genomics

17.02.2026 04:15 👍 13 🔁 6 💬 1 📌 1

Led by Iva Popovic, with Katharine Prata, @melissanaugle.bsky.social le.bsky.social, @ilhabyrne.bsky.social habyrne.bsky.social, Sam Howitt, Tom Bridge, Vero Mocellin, Emily Howells, Line Bay & @couplingdmi.bsky.social lingdmi.bsky.social

#RRAP #AIMS @uq-cbcs.bsky.social

17.02.2026 04:16 👍 3 🔁 2 💬 0 📌 1

This is heartbreaking news. My thoughts are with you and with his loved ones. May he be fondly remembered.

17.01.2026 15:36 👍 2 🔁 0 💬 0 📌 0
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Genomic analyses in Drosophila do not support the classic allopatric model of speciation Abstract. The allopatric model of speciation has dominated our understanding of speciation biology and biogeography since the Modern Synthesis. It is uncon

New paper out: “allopatric” Drosophila species aren’t so allopatric after all. We show that most currently allopatric species pairs probably overlapped in the past and exchanged genes at levels similar to sympatric pairs. @evolletters.bsky.social

doi.org/10.1093/evle... [1/6]

15.01.2026 11:58 👍 57 🔁 26 💬 1 📌 0

Two-way native-invasive introgression and structural variants in invasive moth species. Admixture and exchange of adaptive alleles can facilitate adaptation, but this is also true for pests. Amazing work by @henrylnorth.bsky.social, @chrisjiggins.bsky.social and others, with a lot to think about.

04.01.2026 11:19 👍 11 🔁 3 💬 0 📌 0
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The collision of two genomes threatens global food security Human activity alters selection pressures and species' ranges, creating opportunities for hybridisation through secondary contact. Ancient hybridization has enabled adaptive radiation, but its role in...

Excited about our new preprint showing bidirectional adaptive introgression between invasive and native crop pests over ecological timescales www.biorxiv.org/content/10.6...

26.12.2025 11:21 👍 67 🔁 18 💬 1 📌 4
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What sets the mutation rate of a cell type in an animal species? Germline mutation rates per generation are strikingly similar across animals, despite vast differences in life histories. Analogously, in at least one somatic cell type, mutation rates at the end of l...

Happy to highlight an essay I wrote together with @marcdemanuel.bsky.social,
@natanaels.bsky.social and Anastasia Stolyarova, trying to think through what sets the mutation rate of a cell type in an animal species: www.biorxiv.org/content/10.6... 1/n

22.12.2025 15:09 👍 123 🔁 63 💬 2 📌 1

New preprint from the lab on bioRxiv, led by Grace Zhang!

Quick summary: Lots of studies have examined costs and benefits associated with resistance. Most focus on a single stressor, leaving unclear how resistance shapes fitness and evolution under multiple interacting stresses.

23.12.2025 14:53 👍 10 🔁 5 💬 1 📌 0
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Soyons Nature - 10/12/25 - Radio Campus Montpellier Dans cette émission nous recevons Nicolas Bierne, directeur de recherche au CNRS à l'Institut des Sciences de l'Évolution de Montpellier dans l'équipe biologie évolution marine, venu nous parler de la...

J'ai été interviewé dans l'émission Soyons Nature sur radio campus Montpellier pour expliquer comment l'analyse de l'ADN révèle l'impact des activités humaines sur la biodiversité et l'évolution des espèces marines. www.radiocampusmontpellier.fr/podcast/soyo...

11.12.2025 12:15 👍 5 🔁 0 💬 0 📌 0

"les cellules buissonnières" now translated into English with the title "Hidden Guests". I loved this reading and I offered 5 to friends and family for christmas last year, a suggestion for you folks.

04.12.2025 19:29 👍 3 🔁 1 💬 0 📌 0

Fatigue 😩
"Conditions d’éligibilité - L’appel est ouvert à des jeunes chercheurs ou chercheuses, de toute nationalité, ayant soutenu leur thèse depuis moins de deux ans à la date de prise de fonction. Cette règle des « moins de deux ans » doit impérativement être respectée"

04.12.2025 16:26 👍 0 🔁 0 💬 0 📌 0
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This one is another oyster species (Magallana gigas) and Chr 2, 5, 8 and 9 seems different from the others the same way as >5 and <5 in O. edulis.

03.12.2025 19:59 👍 0 🔁 0 💬 1 📌 0

Thanks for your input, Trevor. What do these kinds of differences mean? No recent genome duplication in this species (Ostrea edulis). The first five chromosomes are metacentric, while the last five are submeta- or subtelocentric. They have more repeats and are preferentially lost in aneuploid cells.

03.12.2025 19:41 👍 0 🔁 0 💬 1 📌 0
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Does anyone here know about Hi-C heatmaps? What do you think of this one? I feel like the patterns of the first and last five chromosomes are different. Would you agree? What do you think that is? Asking for a friend.

02.12.2025 22:52 👍 4 🔁 2 💬 1 📌 0