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Michael Muthukrishna

@michael.muthukrishna.com
1.2K followers 517 following 82 posts

Prof. #NYU & #LSE. Author: A Theory of Everyone. Researching & spreading the word on how humans evolved & what that means for us today. www.atheoryofeveryone.com

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Michael Muthukrishna @michael.muthukrishna.com · 25/08/2026
It's not so much that education makes you American, just more Western. We re-ran the analysis using every country as the reference point & found the same effect for Sweden, the Netherlands, & other Western countries. There's no such correlation w/ non-Western powers such as China, Russia or India 4/
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Michael Muthukrishna @michael.muthukrishna.com · 25/08/2026
Previous studies showed that socioeconomic status can shape people's values & behaviors. Here, we're able to break down SES into education, income & status. Only education seems to make you WEIRDer. 3/
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Michael Muthukrishna @michael.muthukrishna.com · 25/08/2026
🚨 New paper in @NatureComms: (annoyingly) using college students to study cross-cultural effects underestimates the size of cultural differences. More education predicts more Westernization. Income & status don't. w/ Cindel White. 1/
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Michael Muthukrishna @michael.muthukrishna.com · 29/07/2026
Nepotism, cronyism, and other forms of corruption aren't failures of cooperation - they *are* cooperation, but on a lower scale. Our new model extends P&B (2004) but puts people in 2 groups - a local group (L) & a global group (G), w/ the choice to contribute to either or none. 4/
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Michael Muthukrishna @michael.muthukrishna.com · 29/07/2026
In a landmark Nature paper, Panchanathan & Boyd (2004) developed an elegant model showing how reputation can sustain large-scale cooperation: we prefer to help those who've contributed to the public good. If I know you're a patriot or support climate action, I'm more likely to help you elsewhere 2/
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Michael Muthukrishna @michael.muthukrishna.com · 29/07/2026
🚨 PNAS paper: "Indirect reciprocity undermines indirect reciprocity destabilizing large-scale cooperation" w/ Eric Schnell How do we achieve global cooperation on climate or conflict reduction? The problem isn't selfishness as much as it is cooperation itself - at a smaller scale. 1/
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Michael Muthukrishna @michael.muthukrishna.com · 15/07/2026
Important caveats: data and phylogenetically controlled models alone don't tell you the causal mechanism. That's why formal theory is useful - you can model assumptions and logic for possible mechanisms. A lot of the paper explains the role of theory in helping us interpret non-causal analyses. 10/
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Michael Muthukrishna @michael.muthukrishna.com · 15/07/2026
Sociality is the main difference b/w the ABH and SBH. SBH predicts more social species should have larger brains. Sociality was not reliably associated w/ larger brains - in fact perhaps the opposite. 9/
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Michael Muthukrishna @michael.muthukrishna.com · 15/07/2026
Depth also indicates shallower-living species tended to have larger brains. This fits the idea that shallower habitats are generally more calorie-rich, biodiverse, & more cognitively demanding than open-water habitats. Again, consistent w/ the ABH. 8/
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Michael Muthukrishna @michael.muthukrishna.com · 15/07/2026
Results: consistent w/ ABH, ecology predicted brain size. Sociality didn't. The strongest predictor was habitat: cephalopods living on or near the shallow seafloors had larger brains than open water species. The relationship was enormous, ~2/3 as large as the body-brain size relationship. 7/
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Michael Muthukrishna @michael.muthukrishna.com · 15/07/2026
Prior to the CBH, the dominant theory for the evolution of large brains was the social brain hypothesis - brains evolved to cope w/ the demands of group living. Cephalopods are smart - use tools, solve problems, deceive - but they're short-lived, die after reproducing, & even cannibalistic. 3/
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Michael Muthukrishna @michael.muthukrishna.com · 15/07/2026
🚨 New paper in iScience: "Ecological not social factors explain brain size in cephalopods" In 2017, we published the Cultural Brain Hypothesis, a model of human brain evolution. It made an unexpected prediction: non-social animals could evolve big brains too, if their ecology was rich enough. 1/
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Michael Muthukrishna @michael.muthukrishna.com · 14/04/2026
How do you align AI in a world of plural, conflicting, and evolving human values? A starting point is human society itself. @sydneylevine.bsky.social and I are hiring a postdoc at NYU to combine insights from cultural evolution, computational moral cognition, and AI safety. Please share widely!1/
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Michael Muthukrishna @michael.muthukrishna.com · 01/07/2025
Any recommendations for a good evolution oriented intro psych textbook? Gray & Bjorkland's Psychology isn’t being renewed.
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Michael Muthukrishna @michael.muthukrishna.com · 15/11/2024
The first foreign translation book cover is... Korea! Blends elements of the US and UK covers. What do you think?
Theory of Everyone Korean translation book cover
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Michael Muthukrishna @michael.muthukrishna.com · 05/12/2023
The Silk Roads is the best of Big History by the way - an exploration of how people, knowledge, and ideas have flowed back and forth across Eurasia reshaping its civilizations. It meant a lot that Peter read A Theory of Everyone, let alone was willing to blurb it.
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Michael Muthukrishna @michael.muthukrishna.com · 02/10/2023
I love when readers send me their feedback! I'm sure most authors do... Here's a message I received this morning (sharing anonymously with permission) about the section on inequality and inheritance taxes (Chapter 9). atheoryofeveryone.com
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