Study
Explaining evolution of plant communication by airborne signals
Heil, Martin; Karban, Richard
Trends in Ecology & Evolution, 2010
A synthesis addressing the evolutionary problem at the centre of plant communication: why a plant would emit a compound that benefits a competitor. The authors work through the alternatives — within-plant signalling, eavesdropping, kin selection and mutualism with predators of the herbivore — against the available evidence.
- Studied in
- Plantae
- Sample size
- conceptual and empirical synthesis of volatile signalling
The evidence best supports volatiles having evolved for within-plant signalling, with neighbouring plants acting as eavesdroppers on a cue rather than as addressees of a signal. Emitter benefit with respect to neighbours is not established, and the terminology of communication has been applied more widely than the evidence supports.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Airborne plant-to-plant effects are best described as eavesdropping on cues; whether true between-plant signalling exists remains open.
How NatureHQ reads it
This is the paper that supplies the vocabulary the whole subject needs, and the distinction is not pedantry. A signal is a trait that exists *because* of its effect on a receiver — which requires the sender to benefit from being received. A cue is information that leaks out whether or not anyone gains. Almost everything reported as plants talking is the second. The chemistry is not in question and neither is the effect on neighbours; what is in question is whether anything is being sent, and on the current evidence the answer is that a plant is signalling to itself in the open.
- A conceptual synthesis; the alternatives it weighs have not all been tested directly.
- Kin selection and mutualist attraction remain plausible in specific systems and are not excluded.
- Field tests of emitter fitness benefit are extremely difficult and remain scarce.
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Plant communication
Plants do click under stress, in a range no human can hear, and nothing is known to listen
Plant communication
Plants spend a serious part of their income on chemicals pushed into the soil
Plant communication
A warned plant does not defend itself — it gets ready to, cheaply
Plant communication
The best explanation for plants "warning" each other is that each plant is talking to itself and the neighbours are listening in.
Published by: Cell PressPublished in a Cell Press journal.
doi.org/10.1016/j.tree.2009.09.010
Checked against Crossref and OpenAlex 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 2026-08-11.