Noah Egan

Cultural evolution · computational social science

I'm a PhD student in Biology at Stanford, advised by Marc Feldman, where I study cultural evolution. Cultural variants like songs, words and political ideas spread through populations, get copied with variation, and are taken up unevenly. That makes culture an evolutionary system, and I'm interested in how recent structural changes, like the internet and now generative AI, are reshaping how it evolves. Before Stanford I studied computer science at Georgia Tech and worked on collective behavior in social insects.

Projects

Cultural differentiation and city size

Do people in larger cities become more culturally different from one another, or does a city just look more diverse because it holds more people? Using the BookCrossing, MovieLens, and Steam datasets, I measure how between-individual differences in books, movies, and video games scale with city size (up to ~370K users). Larger cities show convergence on popular variants alongside divergence on niche ones, a stronger monoculture and more individual exploration at the same time.

The speed of cultural change in chess and Go

How quickly do top players change their opening moves, and what happened when online servers and superhuman engines arrived? Across 50 years of tournament records (3.45M chess and 116K Go games), I decompose year-over-year change into a shared, population-wide component and an individual one. Chess change is driven mostly by individual exploration, while Go's post-AlphaGo spike reflects shared, population-wide adoption.

Self-assembly in fire ant pontoon bridges

With the Goldman and Randall labs at Georgia Tech, I studied how fire ants build bridges out of their own bodies using only local information. I built an agent-based model and a computer-vision pipeline to quantify the behavior, and helped prove that a Markov-chain model of bridge formation matches experiments.

DISC paper

Coexistence under higher-order interactions

At Princeton I built a spatial Lotka-Volterra model and its mean-field PDE approximation, and found spatial patterns that promote species coexistence only when higher-order interactions between species are present.

Publications

  1. Denton, K., Heinrich-Mora, E., Egan, N., Feldman, M. (2025). Culture is not ecology. Evolution and Human Behavior.
  2. Oh, S., Briones, J., Calvert, J., Egan, N., Randall, D., & Richa, A. W. (2024). Single bridge formation in self-organizing particle systems. International Symposium on Distributed Computing (DISC).
  3. Egan, N., Peixoto, N., & Matto, H. (2020). Creating a personalized cognitive-bias modification therapy exercise in virtual reality using simulated reaction time data. Journal of Student Scientists' Research, 2.

In preparation

  1. Egan, N.*, Zeng, H.*, Platnick, J., Avinery, R., Bagheri, H., Li, S., Sasaki, T., Randall, D., Goldman, D. (2026). Multimodal mechanisms of self-assembly in ant pontoon bridging.

Selected talks & posters

  1. Egan, N., Zeng, H., Avinery, R., Li, S., Bagheri, H., Sasaki, T., & Goldman, D. (2023). Global coordination using local information in fire ant pontoon bridges. Bulletin of the American Physical Society (APS).
  2. Egan, N., Zeng, H., Avinery, R., Bagheri, H., Li, S., Sasaki, T., Goldman, D. (2023). Global coordination using local information in fire ant pontoon bridge simulations. Society for Integrative and Comparative Biology (SICB).