Does the Dear Enemy Hypothesis hold true in a sex role reversed system, Sygnathus scovelli?

• In Event: Systematics and Evolutionary Biology Oral Session & Section Meeting

Abstract

One mechanism organisms have evolved to reduce the costs of prolonged aggression is the Dear Enemy Hypothesis, stating that aggressive behaviors will decrease over time between neighboring individuals of a given species and increase when a novel individual is introduced. Most studies to date on the Dear Enemy Hypothesis focus on territorial males. Here, we tested its applicability in a sex role reversed female, the gulf pipefish Syngnathis scovelli. We predicted these territorial females would display fewer aggressive behaviors to neighbors over time, and more aggressive behaviors toward novel females. We also predicted that aggressive behaviors of dominant females would decrease toward subordinate females after a dominance hierarchy had been established. To test this, we collected mature female S. scovelli from Port Aransas, TX. We used repeated measures ANOVA to observe behaviors across 3 days, measuring aggression and activity of females on both days, allowing time to establish dominance. On day 3, either a novel or familiar female was introduced to the dominant female. To date, data show that dominance is not clearly established across two days. However, for some behaviors, dominant females performed more aggression toward the novel female as predicted. This study sheds light on the general applicability of an established ecological theory in a novel system (sex role reversal) whereby females are territorial and aggressive, rather than males.

Authors

• Sarah Joanne Morton, St. Edward's University

• Briana Martinez, St. Edward's University

• Claire Adams, St. Edward's University

• Ciara Crochet, St Edward's University

• Pam Cisneros, St. Edward's University

• Raelynn Deaton Haynes, St. Edward's University

• Sunny Scobell, St. Edward's University