title: Suppression pheromone and cockroach rank formation.
abstract: Although agonistic behaviors in the male lobster cockroach (Nauphoeta cinerea) are well known, the formation of an unstable hierarchy has long been a puzzle. In this study, we investigate how the unstable dominance hierarchy in N. cinerea is maintained via a pheromone signaling system. In agonistic interactions, aggressive posture (AP) is an important behavioral index of aggression. This study showed that, during the formation of a governing hierarchy, thousands of nanograms of 3-hydroxy-2-butanone (3H-2B) were released by the AP-adopting dominant in the first encounter fight, then during the early domination period and that this release of 3H-2B was related to rank maintenance, but not to rank establishment. For rank maintenance, 3H-2B functioned as a suppression pheromone, which suppressed the fighting capability of rivals and kept them in a submissive state. During the period of rank maintenance, as the dominant male gradually decreased his 3H-2B release, the fighting ability of the subordinate gradually developed, as shown by the increasing odds of a subordinate adopting an AP (OSAP). The OSAP was negatively correlated with the amount of 3H-2B released by the dominant and positively correlated with the number of domination days. The same OSAP could be achieved earlier by reducing the amount of 3H-2B released by the dominant indicates that whether the subordinate adopts an offensive strategy depends on what the dominant is doing.
authors.affiliation: Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan 115, Republic of China. kourong@gate.sinica.edu.tw
authors.forename: Rong
authors.initials: R
authors.lastname: Kou
authors.forename: Huan-Wen
authors.initials: HW
authors.lastname: Chang
authors.forename: Shu-Chun
authors.initials: SC
authors.lastname: Chen
authors.forename: Hsiao-Yung
authors.initials: HY
authors.lastname: Ho
mesh_terms: D000374:Aggression; D000375:Aging / Q000502:physiology; D000378:Agonistic Behavior / Q000502:physiology; D000818:Animals; D003058:Cockroaches / Q000502:physiology*; D004291:Dominance-Subordination; D008297:Male; D008121:Nephropidae / Q000469:parasitology; D010675:Pheromones / Q000032:analysis / Q000037:antagonists & inhibitors / Q000502:physiology*; D012919:Social Behavior; D012930:Social Dominance
chemical_list: D010675:Pheromones