A review of studies on the fire millipede genus centrobolus (diplopoda: trigoniulidae)

Abstract

Studies on Centrobolus spp. were reviewed in which mechanisms of selection, sperm competition and cryptic female choice were studied. Approaches (1) quantify size dimorphism and find the selection pressures operating on the sexes, (2) determine the functional significance of male and female genitalia, (3) understand why there should be a conflict of sexual interests in prolonged copulations, and (4) resolve the mechanisms of sperm competition and cryptic female choice in comparing male mating strategies to female sperm usage were included. 1. Introduction Originally, sexual selection was conceived as operating in two distinct processes of male-male competition and female choice [1]. The distinction between the two processes became modified into male-male competition and epigamic selection because all selections were considered between sexes [2]. Further major theoretical changes took place, one of which was to show how the strength of selection could be measured as offspring production relative to mating success [3]. Sperm competition was the manifestation of male-male competition whereby rival males competed for fertilizations rather than mating per se [4]. Cryptic female choice involved selection for courtship, elaborate male genitalia, and post-copulation products [5, 6]. The dynamics within a mating system may be an evolutionary stable balance between the two mechanisms or the outcome of a conflict of interests between the sexes [7]. Different forms of sperm storage, and the sperm storage organs themselves, determine the use of the remaining rivals' sperm in fertilization [6]. 34 studies on the Centrobolus genus were reviewed in which mechanisms of selection; sperm competition and cryptic female choice were studied. Approaches to: (1) quantify size dimorphism and find the selection pressures operating on the sexes, (2) determine the functional significance of male and female genitalia, (3) understand why there should be a conflict of sexual interests in prolonged copulations, and (4) resolve the mechanisms of sperm competition and cryptic female choice in comparing male mating strategies and sperm precedence to female mating strategies and sperm usage were included. The conclusions from 25 studies were moderated and tabulated here.