Jean-Baptiste André

New @aeon.co essay just out! On how institutions let us scale trust and cooperation - and when things start to unravel.

Big thanks to editor Sam Dresser.

For the more technical version, see thread & paper below👇

#voxprimato #master #sciencescognitives
inscription au Master de sciences cognitives de l'ENS / UPS / EHESS de Paris, avec spécialité en Psychological science, Cognitive neuroscience, Cognitive modeling, neurotheory & AI, Social sciences & humanities, Philosophy, Linguistics
date limite 24/02/2026
👇🏽

Only a few days left to apply to the Cognitive Science Master’s. !!!! Deadline: Feb 24 !!!!

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🗓 Deadline: February 24, 2026 (11:59 pm CET)

🌐 Find more information and apply here: master-cognitive-science.ens.psl.eu/en

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🎓 We welcome candidates from all academic backgrounds, whether in the sciences or humanities.
🌍 Applications are open to both French and international students (all courses are taught in English), and whether you come from a university, a grande école, or have a professional background.

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🧠 Our program offers training at the highest level across all major fields of cognitive science:
- Psychological science
- Cognitive neuroscience
- Cognitive modeling, neurotheory & AI
- Social sciences & humanities
- Philosophy
- Linguistics

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📢 Come study cognitive science in Paris!
The Master’s program in Cognitive Science at @ENS_ULM, @psl_univ, and @EHESS_fr is now accepting applications for the next academic year.

🗓 Deadline: February 24, 2026
💻 Apply here: master-cognitive-science.ens.psl.eu/en/applicati...

Don’t forget to submit your #EHBEA2026 abstract before Dec 15! See you in beautiful Leiden in April! @ehbea2026.bsky.social @ehbea.bsky.social

PhD track in cognitive science | PSL Faire un don

[PhD track in Cognitive Science at Département d'Études Cognitives, ENS-PSL]

Applications are now open for the PSL PhD Track 2026–2027 in Cognitive Science!
This 5-year integrated program is aimed at talented students eager to tackle the scientific challenges of the future and to start shaping 1/2

Help us strengthen trust in climate scientists in the US! Join our megastudy 👇

Overview | EHBEA2026

🚨𝗔𝘁𝘁𝗲𝗻𝘁𝗶𝗼𝗻 𝗲𝘃𝗼𝗹𝘂𝘁𝗶𝗼𝗻 𝗲𝗻𝘁𝗵𝘂𝘀𝗶𝗮𝘀𝘁𝘀!
www.ehbea2026.com is now live for our 2026 European Human Behaviour & Evolution Association (EHBEA) conference in Leiden (NL🇳🇱) Check for 𝗮𝗯𝘀𝘁𝗿𝗮𝗰𝘁 𝘀𝘂𝗯𝗺𝗶𝘀𝘀𝗶𝗼𝗻, first 𝗽𝗹𝗲𝗻𝗮𝗿𝗶𝗲𝘀 & the [𝗔𝗜]𝘃𝗼𝗹𝘂𝘁𝗶𝗼𝗻 𝘁𝗵𝗲𝗺𝗲 𝘁𝗿𝗮𝗰𝗸!
🗓️ 14–17 Apr 2026 | CBEN pre-conf 14 Apr
📍Pesthuis
#EHBEA2026

EHBEACommitteeNominationForm_Pres_Sec.doc EHBEA Committee 2026-2029: Nomination Form The EHBEA Steering Committee is calling for nominations for the following open committee positions for 2026-2029. You are invited to nominate one or more c...

EHBEA is looking for new PRESIDENT and SECRETARY for 2026-2029! 👀

If you know of anybody who could represent EHBEA, nominate them as president!

If you know with good organisational skills, nominate them as secretary!

DEADLINE: 16/12/2026

HERE IS THE FORM 👇

docs.google.com/document/d/1...

Evolutionary parsimony: an equilibrium refinement that sharply constrains the space of outcomes in games with multiple equilibria | Proceedings of the Royal Society B: Biological Sciences Evolutionary game theory loses much of its predictive power in games with multiple equilibria. For such games, this article introduces a simple and general refinement principle, grounded in evolutiona...

6/ Read the article @royalsocietypublishing.org
👉 doi.org/10.1098/rspb...

5/ Main consequence: in plausible evolutionary equilibria, reciprocal cooperation is guided by real cues of mutual benefit, never by bizarre rules tied to arbitrary cues unrelated to payoffs.

4/ What this article shows:

In reality, the bizarre strategies of the folk theorem simply have no chance of ever emerging in the first place. So there is no need for mechanisms to choose between them—the problem is essentially an artefact of misapplied game theory.

3/ The most common solution in the literature: group selection.

Since equilibria are too many, you (supposedly) need group selection to pick the most cooperative ones.

2/ Why is this a problem?
Because it prevents game theory from making precise predictions about social behavior.

1/ The old problem: the folk theorem and the extravagant diversity of equilibria in repeated games.
Game theory allows a proliferation of bizarre, counterintuitive patterns of behavior to qualify as equilibria.

Ever wanted to read about an old problem almost nobody cares about anymore?

Well, I wrote about it.

🧵

Research Fellowships Each year, IAST invites applications for post-doctoral Research Fellowships, which offer candidates an opportunity to devote themselves full-time to their research at the start of their careers. Fello...

📢 Apply to our (2-year) research fellowships at @iast.fr

Join a multidisciplinary, interdisciplinary, transdisciplinary, and indisciplinary group of scholars in Toulouse, walkable/cyclable pink city of chocolatines in the South of France.

Deadline: November 15, 2025.

www.iast.fr/research-fel...

Our #study finds that #male #dominance isn't the norm among #primates, and starts to unravel what shapes flexibility in intersexual power

paper (OA) https://www.pnas.org/doi/10.1073/pnas.2500405122

press release https://www.mpg.de/24986976/0630-evan-beyond-the-alpha-male-150495-x?c=2249

a man in a red jacket is eating a sandwich ALT: a man in a red jacket is eating a sandwich

EHB commentaries on Baumard and André's "The ecological approach to culture" are growing (see "Commentaries" section at the end). Good.
www.sciencedirect.com/journal/evol...

Reconciling Our Three Traditions: Human Behavioral Ecology, Evolutionary Psychology, and Cultural Evolution - HBES – by Nicolas Baumard & Jean-Baptiste André The evolutionary social sciences are grounded in the idea that evolutionary theory provides a unified framework to explain human behavior, including social n...

"a forest is not treated as the output of a second inheritance system or as a group-level adaptation... culture is not a transmitted substance; it is the structured context that emerges from repeated and overlapping individual actions"

Reconciling Our Three Traditions: Human Behavioral Ecology, Evolutionary Psychology, and Cultural Evolution - HBES – by Nicolas Baumard & Jean-Baptiste André The evolutionary social sciences are grounded in the idea that evolutionary theory provides a unified framework to explain human behavior, including social n...

Nicolas Baumard & Jean-Baptiste Andre’s “ecological view of culture” provides an exciting new perspective that links Behavioral Ecology, Evolutionary Psychology, & Cultural Evolution. Read more in their HBES blog post: www.hbes.com/reconciling-...

Here, weird guy from X, I fixed it for you:

"If a scientific society wants to be welcoming to [...] students & researchers [from the Global South], does it make sense to hold its next annual conference in a country that's notorious for [being located in the Global South]?"

The answer is Yes.

We have a lovely new paper out, showing that even ignorant people can be very good at recognising who's knowledgeable based on minimal cues

We often have to judge who is knowledgeable—precisely when we are not. Can humans really do that? Our new paper in Psychological Science shows that, surprisingly, we can. drive.google.com/file/d/1b15E...

figure 2 from our preprint, reporting the results from two experiments we measure moral judgments about dividing money between two parties and manipulate the degree of asymmetry in the outside options each party has we find that moral judgments track predictions from rational bargaining models like the nash bargaining solution and the kalai-smorodinsky solution in a negotiation context by contrast, in a donation context, moral intuitions completely reverse, instead tracking redistributive and egalitarian principles preprint link: https://osf.io/preprints/psyarxiv/3uqks_v1

the functional form of moral judgment is (sometimes) the nash bargaining solution

new preprint👇

I think the BabyLM Challenge is really interesting, but also feel that there is something fundamentally ill-posed about how it maps onto the challenge facing human children. It's true that babies only get a relatively limited amount of linguistic experience, but...

🧵New paper out in Cognition

Why do people moralize harmless carnal sins (e.g. gluttony, masturbation)?

@danielnettle.bsky.social & I find that these behaviors activate reciprocity-based moral judgment—no need for a distinct "purity" module.

50 days free link: authors.elsevier.com/a/1l18D2Hx2-...