Study
Predatory fish select for coordinated collective motion in virtual prey
Ioannou, Christos C.; Guttal, Vishwesha; Couzin, Iain D.
Science, 2012
Presented live bluegill sunfish with virtual prey projected into their tank, whose individual movement rules — attraction to and alignment with neighbours — could be varied directly. Prey "killed" by the fish were removed from the reproducing population, so predation itself selected among movement rules across generations of virtual prey.
- Studied in
- Lepomis macrochirus
- Sample size
- live predators attacking computer-generated virtual prey
Selection by real predators drove the virtual prey towards greater attraction and alignment, producing coordinated collective motion. Prey that grouped and aligned were attacked less successfully.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Predation is sufficient to select for the movement rules underlying schooling, demonstrated directly rather than inferred.
How NatureHQ reads it
An unusually clever design: the prey are simulated so their rules can be manipulated exactly, while the predator is real so the selection is genuine. It closes the loop between individual movement rules and the collective pattern, which observation of real shoals cannot do.
- Virtual prey lack the escape responses, hydrodynamics and appearance of real fish.
- One predator species in a tank, and the projected environment is highly simplified.
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Group defence
A group helps in three separate ways: your share of the risk falls, targeting gets harder for the predator, and you can put somebody between yourself and it. Only the second needs the group to look alike.
Group defence
A predator’s success drops sharply against a large shoal — until a few individuals look different. Odd ones are taken far out of proportion, and their presence restores the predator’s success against the whole group.
Published by: American Association for the Advancement of SciencePublished in Science or Science Advances (AAAS).
doi.org/10.1126/science.1218919
Checked against Crossref on 2026-09-28, and they agree on the title, the authors and the year.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-09-03.