Why do societies rely on rigid moral rules? Don't lie. Keep your promises. Don't steal. We all recognize there are good reasons to make exceptions. So why are moral rules so often categorical? Our new paper proposes an answer. 🧵

Last week, we talked to @kris-smith.bsky.social about cooperation in the field. youtu.be/ADvkjnwxasA podcasts.apple.com/us/podcast/e... www.podbean.com/eas/pb-i6c8y...

Cooperation in the field with Kris Smith

YouTube video by Evolutionary Psychology (The Podcast)

youtu.be

(Undergrad here) Wait, journals actually ask authors to suggest peer reviewers??? Is this the researcher version of students having a class presentation and giving their classmates questions to ask them during Q&A so they can prepare answers in advance LOL

New preprint led by @lucasmolleman.bsky.social investigates social information use across the human lifespan. Testing >40,000 participants aged 6-80 in museums in Berlin and Japan. psyarxiv.com/hec96

Another new preprint from my lab, led by Erin McHugh in collaboration with Megan Bontrager. Mutualism has long been thought to expand a species' niche, an idea supported by case studies. We found support (mostly) for this idea across 2600+ legumes from around the globe: doi.org/10.64898/202...

Do you stay home or go out when you're sick? This week, we talk to @joshackman.bsky.social about the psychology of pathogens. youtu.be/Jq3K_Ck0EQY podcasts.apple.com/us/podcast/e... www.podbean.com/eas/pb-29ph7...

Pathogens with Josh Ackerman

YouTube video by Evolutionary Psychology (The Podcast)

youtu.be

Why is lower wealth often associated with greater empathy? New work at SPPS w @jessicadayers.bsky.social Yul Kwon Peter Todd @athenaaktipis.bsky.social shows lower wealth cultivates empathy via challenges and helping - but only among moderate helpers🧵https://doi.org/10.1177/19485506261449280

Helping People in Times of Need Cultivates Empathy Over Time - Diego Guevara Beltran, Jessica D. Ayers, Jung Yul Kwon, Peter M. Todd, Athena Aktipis, 2026

Why is lower social class often associated with greater empathy? We test whether less wealthy people experience more challenges, thereby motivating them to help...

doi.org

Announcing new diacritical improvements in eHRAF hraf.yale.edu/font-selecti...

Thinking about pursuing a career in personality and social psychology? Jessica D. Ayers recommends having fun, finding a topic you're passionate about, and striving to find work-life balance. Learn more in our latest SPSP Member Spotlight: https://ow.ly/MKzi50Z4T5v

Why is lower wealth often linked to greater empathy? New research suggests it comes down to experiencing more challenges, helping others more, and building empathy over time. Read more in #SPPS: https://ow.ly/jXZb50Z4KZE

What makes religious fasting prosocial? Hunger usually makes people more selfish, impulsive, and aggressive — so why does fasting seem to do the opposite? That was the question at the heart of my talk at the 37th meeting of the Human Behavior and Evolution Society in Rabat, Morocco last week.

Maybe it depends on how concerned about germs you are (www.sciencedirect.com/science/arti...)? 😀 Wish we knew about your measure when we did our studies! Cool stuff.

Infectious disease concerns predict narrow friendship networks

Friendship significantly influences our happiness and health, and in ancestral contexts, the support offered by friends would likely have delivered fi…

sciencedirect.com

Do you want a lot of friend, or only a few that your really close with? In our new paper, we ( @psycheddiego.bsky.social D. Mercado & @athenaaktipis.bsky.social) present the concept, structure, and validation of friendship making orientation kwnsfk27.r.eu-west-1.awstrack.me/L0/https:%2F...

Online Now: How developing prosocial motivations shape children’s altruism

How developing prosocial motivations shape children’s altruism

Developmental perspectives are crucial to harnessing the human potential for altruism. We synthesise and highlight recent research on the motivations underlying children’s (costly) prosocial behaviour. The order in which children develop intrinsic, extrinsic, and strategic motivations to benefit others has implications for efforts to positively impact young people’s lives.

dlvr.it

There is a fully-funded PhD position at the Max Planck Institute for Evolutionary Anthropology to pursue dissertation research among the Mayangna of Nicaragua, expanding a longitudinal study of subsistence strategies and behavioral ecology. Please share the posting! www.eva.mpg.de/career/posit...

How do people respond to a partner’s positive and negative outcomes when faced with challenging information? We (Shanshan Ma Erin Maresh Andrea Coppola @mehlmr.bsky.social Jessica Andrews-Hanna & @dsbarra.bsky.social) tackle this in new work at Affective Science: link.springer.com/article/10.1...

Our work investigating how sources of fitness interdependence are associated with shared fate (summary estimate of interdependence) and guide cooperation in a small-scale subsistence society is available at EHB (see thread for summary) www.sciencedirect.com/science/article/pii/S1090513825001515

Sources of fitness interdependence associated with shared fate and cooperation in a small-scale horticultural society

Cooperation often relies on people's ability to discern in whom to invest their limited resources. One solution to this partner choice dilemma entails…

sciencedirect.com

Diego Guevara Beltran@psycheddiego.bsky.social · last yr.

How do people know whom, and how much, to help? we (@jessicadayers.bsky.social @leecronk.bsky.social Daniel Balliet @jeremykoster.bsky.social & @athenaaktipis.bsky.social) tackle this question among the Mayangna of northern Nicaragua, who rely primarily on horticulture for subsistence 🧵(1/10).

How do people know whom, and how much, to help? we (@jessicadayers.bsky.social @leecronk.bsky.social Daniel Balliet @jeremykoster.bsky.social & @athenaaktipis.bsky.social) tackle this question among the Mayangna of northern Nicaragua, who rely primarily on horticulture for subsistence 🧵(1/10).

Application still open! Are you interested in interdependence and cooperation, understanding the psychology of people living in subsistence communities, cross-cultural generalizability + variation? This might be the right place for you!

Diego Guevara Beltran@psycheddiego.bsky.social · 7mo ago

The SPECIEs Lab (Psychology department - UArizona) is looking for a postdoctoral fellow to join the team (please share)! Start date: Summer-Fall 2026 Review: until filled Duration: 3-years Materials: 1-2 page cover letter, CV, 2-3 reference contacts Send materials to: dguevarabeltran@arizona.edu

Updated application portal is now live! arizona.csod.com/samldefault....

Diego Guevara Beltran@psycheddiego.bsky.social · 7mo ago

The SPECIEs Lab (Psychology department - UArizona) is looking for a postdoctoral fellow to join the team (please share)! Start date: Summer-Fall 2026 Review: until filled Duration: 3-years Materials: 1-2 page cover letter, CV, 2-3 reference contacts Send materials to: dguevarabeltran@arizona.edu

The SPECIEs Lab (Psychology department - UArizona) is looking for a postdoctoral fellow to join the team (please share)! Start date: Summer-Fall 2026 Review: until filled Duration: 3-years Materials: 1-2 page cover letter, CV, 2-3 reference contacts Send materials to: dguevarabeltran@arizona.edu

I’m happy to announce that our paper "The Meanings and Dividends of Man the Hunter" has now been published in Evolution and Human Behavior. www.sciencedirect.com/science/arti...

New paper with Ben Morris and Alex Shaw out last week in @cognitionjournal.bsky.social! We find that children are sensitive to who has better evidence when evaluating how people behave in disagreements. www.sciencedirect.com/science/arti... 1/3

Calibrated deference: Children's evaluations of responses to disagreement across knowledge gaps

Declaring that you are right or wrong is not merely a factual matter, but often a deeply social decision about when to own up to the limits of your kn…

sciencedirect.com

New study just out! 🚨 We created a way to rewind and fast forward through cultural differences in China. www.nature.com/articles/s41... @natureportfolio.nature.com

Interdependence strongly guides partner choice, giving help, and getting help from people in your network #EPatSPSP2026 @spspnews.bsky.social

@psycheddiego.bsky.social talks to us about cooperation and interdependence in the Mayangna

New article out exploring great ape name recognition! We find partial evidence that zoo-living chimps & bonobos know each other's names 👀 Huge thanks to Animal Behavior and Cognition (a great open-access journal) & co-authors for your collaboration!🎉🐵 unsvr1.com/web/abc/work...

Do Great Apes Know Each Other's Names? Probing Great Ape Comprehension of Social Vocal Labels — Animal Behavior and Cognition

unsvr1.com

How do people decide whom to help when cooperation is costly and resources are limited? Kinship and reciprocity are not the full story—research by @psycheddiego.bsky.social et al suggests shared fate (the other person’s outcomes influences one’s own) complements: buff.ly/fRinBjR

Introducing PowerLMM.js! A new tool for power analysis of longitudinal linear mixed-effects models (LMMs) – with support for missing data, plus non-inferiority and equivalence tests. powerlmmjs.rpsychologist.com Would really appreciate your feedback as I refine this app! Details below 🧵👇

As we head toward #SAS2026 we are excited to partner with @inclivio.com to support EMA research in affective science. If you’re attending the conference, like (1 entry) and repost (3 entries) this post to enter a drawing for 1 of 3 licenses to run your study on Inclivio for *free*. inclivio.com