# Combat behaviors predictive of fight outcome in Gromphadorhina portentosa

## TL;DR

This study explores how prior wins affect future combat outcomes in Madagascar hissing cockroaches, even when they face much larger opponents.

## Contribution

The study investigates the winner effect in Madagascar hissing cockroaches, focusing on combat behaviors predictive of success in mismatched size contests.

## Key findings

- Smaller winner-affected males showed increased chances of winning against larger males.
- Certain combat behaviors were predictive of winning regardless of treatment group.
- The study identifies behavioral indicators of combat success in Gromphadorhina portentosa.

## Abstract

In the winner effect, animals that have previously won an aggressive encounter gain an increased probability of winning subsequent aggressive interactions. This effect has been studied in males of various species, from crickets to humans. However, the effects are under-studied in Madagascar hissing cockroaches,
Gromphadorhina portentosa.
Here, we aimed to determine the influence of the winner effect in unfavorable conflicts. To test this, smaller winner-affected male
G. portentosa
were placed in combat trials against substantially larger males. We tested the limits of the winner effect, and identified behaviors that were predictive to winning a match regardless of treatment group.