Study
Arms races between and within species
Dawkins, Richard; Krebs, John R.
Proceedings of the Royal Society of London B, 1979
Sets out the logic of reciprocal evolutionary escalation between predators and prey, and introduces the asymmetry that a failed escape is fatal for the prey while a failed hunt is a missed meal for the predator.
- Studied in
- Animalia
- Sample size
- conceptual paper
Selection on prey to escape is typically stronger than selection on predators to catch, because the two sides are not playing for the same stakes — the life–dinner principle.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Arms races are asymmetric, and that asymmetry predicts which side tends to be ahead on any particular trait.
How NatureHQ reads it
The conceptual backbone of the arms-race page, and the source of its central caution: an arms race is a description of reciprocal selection, not a plan. Neither side is trying to do anything. The paper is also careful that the metaphor can mislead, which is the part popular retellings drop.
- A conceptual paper: it frames a research programme rather than reporting measurements.
- The life–dinner principle is a tendency with well-known exceptions, particularly where a failed hunt is itself dangerous.
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Predator–prey arms races
Prey do not evolve defences in order to defeat a predator. Each side changes because the other side has changed, over generations, with nothing aiming at anything.
Armour and spines
Armour costs weight, speed and flexibility, so it pays where those matter less than being bitten. In marine snails the escalation is visible in the fossil record: shells thickened as shell-crushers diversified.
Armour and spines
A shell keeps the record of what happened to it. Repaired breakage scars are attacks the animal survived; drill holes are attacks it did not — so a fossil assemblage preserves both outcomes.
Published by: The Royal SocietyPublished by the Royal Society.
doi.org/10.1098/rspb.1979.0081
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.