It isn't a scream

In March 2023, a lab at Tel Aviv University reported something no one had recorded before: thirsty plants make noise, and the noise carries. Sealed in an acoustic chamber, dehydrated tomato plants clicked dozens of times an hour; cut tomato and cut or dehydrated tobacco clicked too, a little less often, at 40–80 kHz — roughly one to two octaves above the top of human hearing (Khait, Lewin-Epstein, Sharon, Saban et al., led by Lilach Hadany and Yossi Yovel, Cell 186(7), 2023). A machine-learning model trained on the recordings could tell a thirsty plant from a cut one, and one species from another, from the clicks alone. The team's own estimate: a moth or a mouse could pick the sound up from as far as five metres away — well outside the plant's own reach.

None of that is what put the word “scream” in a thousand headlines. A click a model can classify is not the same thing as a signal a plant means to send, and the paper itself claims only that the sound exists, carries, and is informative — never that anything sent it on purpose. What actually makes the noise is still, by the researchers' own account, a guess: air bubbles nucleating and collapsing inside the plant's water-conducting tissue as drought tension pulls the water column past its breaking point, a process called cavitation. It's a good guess with real company — cavitation's own clicks have been recorded directly, transducer clipped straight to the wood, since at least Ponomarenko, Vincent, Pietriga, Cochard, Badel & Marmottant caught individual bubbles that way in 2014 (J. R. Soc. Interface 11(99)), itself standing on decades of contact acoustic-emission work before it. But a transducer touching the wood and a moth hearing a click across open air are not the same claim, and nobody has yet shown the two are the same event.

So the study that got to keep “scream” in a thousand headlines is careful, in its own text, not to use it — and the mechanism most of those headlines quietly assumed is sitting exactly where cavitation left it in 2014: the leading explanation, not a confirmed one. This garden's own rule is to name a gap like that rather than paper over it with a mechanism that sounds more finished than the evidence is. It turns out a research team can hold that same line under a much brighter spotlight than this one ever gets.