---
title: "Fish shoals · Collective systems · Entities · Simulation Hypothesis"
url: https://simulation-hypothesis.com/entities/c-fish
description: "Shoals use quorum rules to decide. Large groups can sense environmental gradients that no single fish can."
license: https://creativecommons.org/licenses/by/4.0/
credit: "Ross Allan Dahl, Simulation Hypothesis (simulation-hypothesis.com)"
---

[Entities](https://simulation-hypothesis.com/entities) › Collective systems

# Fish shoals

Shoals use quorum rules to decide. Large groups can sense environmental gradients that no single fish can.

What’s measured

The rules individual fish follow when they interact, and the quorum-based decisions shoals make.

## Evidence

* Shoals use quorum rules to decide. Large groups can sense environmental gradients that no single fish can.  
Ward AJW, Sumpter DJT, Couzin ID, Hart PJB, Krause J (2008) Quorum decision-making facilitates information transfer in fish shoals. Proc Natl Acad Sci USA 105(19):6948-6953\. doi:10.1073/pnas.0710344105.

Research on collective intelligence studies how groups decide. It doesn't claim that the group itself has experiences.