Magic mushroom chemical calms fighting fish? Or just slows them
- Claim
- MAGIC MUSHROOMS CALM FIGHTS?
- Catch
- CALMER, OR JUST SLOWER?
- Verdict
- A FISH CLUE, NOT A CURE
Headlines said a "magic mushroom ingredient takes the fight out of aggressive fish." The study, by researchers at Acadia University and the University of British Columbia in Frontiers in Behavioral Neuroscience (2026), tested the mangrove rivulus, a small killifish known for attacking its own kind. Each fish was filmed facing a rival behind a mesh barrier, then soaked for 20 minutes in water containing psilocybin (3,000 µg/L) or plain water, and filmed again. With 16 fish per group, the psilocybin fish made fewer high-energy swimming bursts, the lunging moves that mark an escalating attack (a medium-sized effect), and spent less time moving overall. The catch: other aggressive behaviours, including head-on and lateral threat displays, time near the barrier and time interacting, fell over time in the plain-water fish too, with no clear psilocybin-specific effect. Because treated fish also moved less in general, part of the "calming" may simply be reduced activity. The study used 32 fish, a single dose and a single short exposure, and measured no brain chemistry or serotonin receptors. The researchers themselves say this is not evidence of a treatment for human aggression.
SOURCES
- Forsyth, Faraone, Lamarre & Currie (2026), "The magic of mushrooms: psilocybin influences behavior in the mangrove rivulus fish, Kryptolebias marmoratus," Frontiers in Behavioral Neuroscience 20. DOI: 10.3389/fnbeh.2026.1767175
- Frontiers news release, May 2026
For information only. Psilocybin is a controlled substance in most countries; this is not a recommendation to use it.
For information only, not medical advice. Talk to a qualified health professional before changing your diet, supplements or treatment.
