Study
Plant "primary perception": electrophysiological unresponsiveness to brine shrimp killing
Horowitz, Kenneth A.; Lewis, Donald C.; Gasteiger, Edgar L.
Science, 1975
A direct replication of the widely publicised claim that plants respond electrically to the death of nearby organisms. Brine shrimp were killed automatically at randomised times while plant electrical activity was recorded continuously, with the plants electrically shielded and the analysis performed without knowledge of when killings occurred.
- Studied in
- Philodendron
- Sample size
- replicated automated trials with blind analysis
No relationship was found between the killings and the plants' electrical activity. Apparent responses of the kind previously reported appeared in the records regardless of whether anything had been killed, and disappeared once timing was randomised and the analysis blinded.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
The reported phenomenon of plant "primary perception" does not survive controlled replication; the original observations are explicable as unblinded interpretation of ordinary electrical noise.
How NatureHQ reads it
Worth carrying half a century later, because the claim it killed has never stopped circulating. The original was a polygraph examiner reporting that his houseplant reacted to harm — a story that went round the world and is still the ancestor of most "plants sense your intentions" material. The replication is a small model of how to test something like this: automate the killing so no human decides when, shield the plant, and analyse the trace without knowing what happened when. All three matter, and the effect vanished. The plant electrical signalling that *is* real, and that the modern papers describe, is a different phenomenon entirely — a wound response with a known mechanism, not perception at a distance.
- A negative result, which cannot exclude an effect smaller than the design could detect.
- One plant type in one laboratory.
- Addresses the specific claim as originally framed rather than every subsequent variant of it.
The houseplant, the polygraph and the brine shrimp
Do plants react electrically when something is killed nearby?
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Published by: American Association for the Advancement of SciencePublished in Science or Science Advances (AAAS).
doi.org/10.1126/science.189.4201.478
This reference was resolved automatically against Crossref on 2026-08-11.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-08-11.