The Influence of Size Differential On Agonistic Encounters in the Mantis Shrimp, Gonodactylus Viridis

Abstract

AbstractThe influence of size on the aggressive behavior of Gonodactylus viridis was examined by matching large animals against others 50, 60, 70, 80, 90, and 100% their size. With size discrepancies of 10% or greater, the larger animals won significantly more of their fights. The smaller participants of a contest avoided more, attacked less, and threatened more than did their larger opponents. When the contestants were evenly matched, attack and avoid values were intermediate, but the animals threatened as often as did the smaller animals. These results are reviewed in light of recent game theory analyses which suggest that threat should be used by the smaller contestant or when the risk of escalation is great compared to the expected pay-off.