Study
Biochemistry at 100 °C: explosive secretory discharge of bombardier beetles (Brachinus)
Aneshansley, Daniel J.; Eisner, Thomas; Widom, Joanne M.; Widom, Benjamin
Science, 1969
Measured the temperature of the bombardier beetle’s defensive discharge directly, and established the chemistry: hydroquinones and hydrogen peroxide stored separately, mixed with catalytic enzymes in a reaction chamber at the moment of use.
- Studied in
- Brachinus
- Sample size
- beetles with discharge temperature measured directly
The discharge leaves the beetle at approximately 100 °C. The reactants are stored apart and are harmless together only until enzymes are added; the reaction converts hydroquinones to benzoquinones and releases enough heat to bring the mixture to boiling point.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
The beetle stores the components of an exothermic reaction separately and combines them on demand, producing a hot, chemically irritant spray.
How NatureHQ reads it
The measurement behind a claim that is usually exaggerated in one direction and dismissed in the other. It really does reach about 100 °C — that is measured, not folklore — and it is a small volume in brief pulses rather than a jet of boiling liquid. Both halves matter.
- Temperature measured at discharge under laboratory conditions; what an attacker experiences depends on distance and volume.
- One genus, and bombardier beetles vary in chemistry and delivery.
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.165.3888.61
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.