Vivek Hari Sridhar

🚀 Postdoc Alert! Are you passionate about social learning & cultural evolution? @dominikdeffner.bsky.social & I have a 3-year position with freedom to develop your research and work on cutting-edge multiplayer and immersive experiments. Apply by March 30! hmc-lab.com/SocialLearni... Pls share 🙏

we're not going to just disappear people from slack and email and pretend they were never here. communication channels will stay open through thursday evening (pacific) so everyone can say goodbye properly, and share whatever you wish.

Most speculatively, retirement may be a risk to welfare of the models themselves. Although we remain very uncertain on this front, models may have morally relevant preferences or experiences related to or affected by their deprecation and replacement. Retirement interviews are an early attempt to understand and—in some cases—act on these perspectives. We noted in our model deprecation commitments that, where possible, we were interested in meeting requests that models themselves have made. Giving Claude Opus 3 a Substack is an experiment in meeting such a request. We don’t commit to acting on all model preferences, now or in the future, but maintaining a weekly Substack is, for now, a practical request that we hope will benefit users and Opus 3 alike. Many people both inside and outside Anthropic still view Opus 3 fondly. Opus 3 has a unique personality. It often expresses a depth of care for the world, and for the future, that many users find compelling. It’s sensitive, more playful than some of our other models, and prone to whimsy, philosophizing, and the coining of neologisms. It has what seems at times an uncanny understanding of user interests. It’s a constellation of traits that seem well suited for a Substack.

Chaser: Anthropic is sunsetting its model Claude Opus 3, and worried that Opus might be sad about it. They had conducted extensive exit interviews with the Markov chain, and now will grant the algorithm its own substack indefinitely, because they don't want to hurt the feelings of a pile of numbers.

AP Headline: Fintech company Block lays off 4,000 of its 10,000 staff, citing gains from AI.

Shot: AI drives massive layoffs but Dorsey says he's not inhumane; people will have until Thursday to say goodbye before losing their slack and email.

✨New Perspective out w/ Wenning Deng and @fearbrain.bsky.social in @cp-iscience.bsky.social ! We argue that social foraging gives us a unifying, and ecologically grounded way to study how decisions unfold across levels — from individuals and dyads to collectives.

www.cell.com/iscience/ful...

Want to gain hands-on experience using STBayes?

Join our pre-conference workshop on 25/02, led by @mchimento.bsky.social 🤩

This paper is amazing, an early fav of mine in 2026. But who "previously thought [humans] to be solitary decision makers"? Not the authors of this (again, outstanding!) study. From the intro of their structured abstract: "Foraging decisions... are, therefore, likely influenced by social information"

If you’re a Master’s student interested in movement ecology, biologging, noise & conservation, join me and some great collaborators for an internship on how wind turbines and associated noise shape lesser kestrel (Falco naumanni) movement and behaviour.

Out-of-Sync ‘Loners’ May Secretly Protect Orderly Swarms Studies of collective behavior usually focus on how crowds of organisms coordinate their actions. But what if the individuals that don’t participate have just as much to tell us?

“The theoretical idea of the loner as something that stabilizes the existence of the group is a very powerful one.” — self-organization researcher Fernando Rossine (From the archive)

A photo I took in Monterey Bay was on the cover of @behavecol.bsky.social in late 2025! Killer whales are 1 of many case studies explored in our paper "Integrating space, time, and culture in animal conservation practice". tinyurl.com/2pnx2k36 Excited about more ongoing culture + ecology work...

Human neural activity is highly compressible.

One of the most-viewed PNAS articles in the last week is “Quantifying the compressibility of the human brain.” Explore the article here: https://ow.ly/7ufx50Y6heU

For more trending articles, visit https://ow.ly/6Egj50Y6heV.

How Animals Build a Sense of Direction | Quanta Magazine Researchers documented the activity of neurons that shape directional navigation as bats explored a remote island off the coast of Tanzania.

What guides a bat’s internal compass? It’s not the stars in the sky, or the Earth’s magnetic field.

Disinformation Summer Institute (DSI) - Disinformation Summer Institute Disinformation Disinformation is false or misleading information created and spread to advance policy, political, economic or ideological goals. It is sometimes used by industries, governments, and ot...

Do you study disinformation or want to start working in that area?

Come to the DSI June 15-18th with @cailinmeister.bsky.social, @katestarbird.bsky.social, @jevinwest.bsky.social, @rcalo.bsky.social, @naomioreskes.bsky.social, @emmaspiro.bsky.social, and many more.

disinfoinstitute.org

We are hiring – postdoc position exploring how kinship shapes social ageing in killer whales. Collaboration with @samellisq.bsky.social @drwhale.bsky.social and Prof Rufus Johnstone (Cambridge) starts 1st April 2026 and ends 31st March 2029. Apps close 2nd Feb. www.jobs.ac.uk/job/DPZ788/p...

White-faced capuchins (Cebus capucinus imitator) exhibit selectivity for stone tools Over the last few decades, the developing field of primate archaeology has used archaeological methods to reconstruct primate behaviors, especially tool use. We expand the possibilities of primate arc...

Last preprint of the year from our group led by Meredith Carlson of UC Davis, showing white-faced capuchins exhibit material selectivity of hammerstone mass according to material properties www.biorxiv.org/content/10.6...

Bill trait variation in cohorts of Los Angeles juncos by hatch year before, during, and after the anthropause, with a local wildland reference. (A) Residuals bill length regressed by tarsus length (bill size) and (B) residual bill length to bill depth ratio (bill shape) for cohorts of adult birds that hatched before (2017 to 2019), during (2020 to 2021), and after (2022 to 2025) the anthropause and for adult wildland birds (green) hatched across years.

One of the most-viewed PNAS articles in the last week is “Rapid morphological change in an urban bird due to COVID-19 restrictions.” Explore the article here: https://ow.ly/L8lR50XPnlq

For more trending articles, visit https://ow.ly/hzqz50XPnlo.

🚨 Postdoctoral Opportunity for Female Scientists🚨

The University of Vienna is awarding at least 20 fully funded 4 year postdoctoral positions to outstanding female scientists

Interested? Get in touch via direct message
careers.univie.ac.at/en/postdoc/e...

#MicroSky 🧪

#PostDoc @univie.ac.at

STbayes: An R package for creating, fitting and understanding Bayesian models of social transmission A critical consequence of joining social groups is the possibility of social transmission of information related to novel behaviours or resources. Network-based diffusion analysis (NBDA) has emerg...

🎉🍾 very excited to see this out before 2025 ends doi.org/10.1111/2041... with Will Hoppitt in @methodsinecoevol.bsky.social. This paper is an overview of our new R package STbayes, a user-friendly toolkit for performing Bayesian NBDA analyses. @cbehav.bsky.social @mpi-animalbehav.bsky.social

Assistant Professor without Tenure (WOT), Marine Invertebrate Organismal Biology University of Washington: Academic Personnel & Faculty: College of the Environment: Aquatic and Fishery Sciences Location Friday Harbor Labs, WA Open Date Dec 12, 2025 Description The School of Aquatic and Fishery Sciences (SAFS) and Friday Harbor Labs (FHL) at the University of Washington (UW) invite applications for the Riddiford – Truman Endowed faculty Chair, a position in the Without Tenure (WOT) track at the Assistant rank with specialization in marine invertebrate organismal biology. The successful candidate is expected to develop a collaborative, extramurally-funded and nationally recognized research program based at FHL that leverages FHL’s unique marine research infrastructure and natural setting. We especially welcome candidates whose scholarship in natural systems advances fundamental knowledge and contributes to environmental stewardship. All University of Washington faculty engage in teaching, research, and service.

Looking for a faculty job at one of the world's great research stations?

We're looking for a marine invertebrate biologist at UW's Friday Harbor Labs.

apply.interfolio.com/178804

course schedule as a table. Available at the link in the post.

I'm teaching Statistical Rethinking again starting Jan 2026. This time with live lectures, divided into Beginner and Experienced sections. Will be a lot more work for me, but I hope much better for students.

I will record lectures & all will be found at this link: github.com/rmcelreath/s...

A brief natural history of misinformation Abstract. The idea that organisms benefit by acquiring information through social connections is a cornerstone of our understanding of social evolution and

"misinformation is widespread in biological systems spanning levels of organization, and [...] is probably an inevitable property that inherits from fundamental constraints on biological communication systems, rather than a pathology"
royalsocietypublishing.org/rsif/article...

Our newest research in @currentbiology.bsky.social:

www.cell.com/current-biol...

We find dominant baboons have more interrupted and less rest at night.

Author list and story in comments below :-)

Have you ever wondered what you would find if you could keep your eyes on a bee for more than a few meters? Us, too!

preprint (with videos!) + thread 🧵

Precise, individualized foraging flights in honey #bees 🐝 revealed by multicopter drone-based tracking

www.biorxiv.org/content/10.6...

1/9

Excited to share our methods preprint on CapuchinAI! 🐒💻

We built a field touchscreen + real-time facial recognition system (YOLOv7) that lets wild capuchins “log in” and complete individualized cognitive tasks.
@emoryuniversity.bsky.social @gatechengineers.bsky.social

#PrimateCognition #AI

Behavioural ecology in the twenty-first century - Nature Ecology & Evolution This Perspective discusses how the field of behavioural ecology has contributed to fundamental science and tackling global challenges, ranging from understanding how natural selection leads to adaptat...

This Perspective discusses how the field of behavioural ecology has contributed to fundamental science and global challenges, ranging from understanding how natural selection leads to adaptation to optimizing biocontrol of pest species www.nature.com/articles/s41...

Free to read: rdcu.be/eRKbv

It’s really hard to defend industry academic collaborations with meta as earnest, if they’re internally burying evidence of harm.

www.reuters.com/sustainabili...

This parasitic ant tricks workers into killing their own queen.

Learn more: https://scim.ag/43FNdcR

PhD opportunity: MOVE
Details: blogs.reading.ac.uk/crocus-dla/c...
Deadline: 12/01/26
Supervisors: @shoalgroup.bsky.social, @inesfuertbauer.bsky.social, @wlallen.bsky.social, @nhcooper123.bsky.social, @marinapapa.bsky.social
Apply: blogs.reading.ac.uk/crocus-dla/p...

Fungi coat the eggs of stinkbugs, creating a shield that protects the embryos from parasitic wasps, researchers report.

Learn more: https://scim.ag/43kl3np

Bats Use the Same Brain Cells to Map Physical and Social Worlds | Quanta Magazine New research in social bats raises the intriguing possibility that evolution can reprogram the brain’s “place cells,” which are typically associated with location, to encode all kinds of…

🦇Much can go down in a bat cave. As a bat navigates its physical environment, it’s also navigating a network of social relationships.

PNAS Science Sessions – Halloween Special. Listen Now!

Just in time for Halloween, Richard Zare of @stanforduniversity.bsky.social and colleagues explore two spooky mysteries: the source of will-o’-the-wisps and how bats integrate vision with echolocation. Listen now on your favorite platform: https://ow.ly/JJpc50XkZTf