We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Sexual Selection on Accessory Glands, Genitalia and Protarsal Pads in the Whirligig Beetle Dineutus nigrior Roberts (Coleoptera: Gyrinidae).
- Authors
Fairn, Evan R.; Schulte-Hostedde, Albrecht I.; Alarie, Yves
- Abstract
Sexual selection is a potent force in the evolution of morphology in sexually reproducing species. When large size in a trait is favored by sexual selection the trait often exhibits positive allometry. Mating behavior in whirligig beetles consists of males attempting to grasp reluctant females using enlarged protarsi (protarsal pads). Here we use allometry and a mating experiment to investigate sexual selection pressures on accessory glands, intromittant genitalia (aedeagus), and protarsal pads in males of the whirligig beetle Dineutus nigrior Roberts. Accessory gland size exhibited positive allometry and males with larger accessory glands were more likely to copulate suggesting that larger size in this trait is favored by sexual selection. Males with larger accessory glands attempted to copulate more often but did not exhibit fewer failed mating attempts before copulating. This suggests that the increased probability of mating in males with large accessory glands is due to higher mating attempt frequency and not to increased ability to overcome female resistance. The length of the aedeagus exhibited negative allometry and males with a longer aedeagus did not have increased mating success. This is consistent with stabilizing selection favoring an intermediate size in this trait. The allometric slope of the protarsal pad did not differ from isometry and males with larger protarsal pads did not have increased mating success. This suggests that larger protarsal pads are not favored by sexual selection.
- Subjects
GYRINIDAE; SEXUAL selection; GLANDS; GENITALIA; BEETLES; ANIMAL morphology
- Publication
Ethology, 2007, Vol 113, Issue 3, p257
- ISSN
0179-1613
- Publication type
Article
- DOI
10.1111/j.1439-0310.2006.01315.x