Title: | Parthenogenetic Females of the Stick Insect Clitarchus hookeri Maintain Sexual Traits |
Author(s): | Nakano M; Morgan-Richards M; Godfrey AJR; Clavijo McCormick A; |
Address: | "School of Agriculture and Environment, Massey University, Palmerston North 4474, New Zealand. School of Fundamental Sciences, Massey University, Palmerston North 4474, New Zealand. School of Agriculture and Environment, Massey University, Palmerston North 4474, New Zealand. a.c.mccormick@massey.ac.nz" |
ISSN/ISBN: | 2075-4450 (Print) 2075-4450 (Electronic) 2075-4450 (Linking) |
Abstract: | "The New Zealand stick insect Clitarchus hookeri has both sexual and parthenogenetic (all-female) populations. Sexual populations exhibit a scramble competition mating system with distinctive sex roles, where females are signalers and males are searchers, which may lead to differences in the chemical and morphological traits between sexes. Evidence from a range of insect species has shown a decay of sexual traits is common in parthenogenetic lineages, especially those traits related to mate attraction and location, presumably due to their high cost. However, in some cases, sexual traits remain functional, either due to the recent evolution of the parthenogenetic lineage, low cost of maintenance, or because there might be an advantage in maintaining them. We measured morphological and chemical traits of C. hookeri to identify differences between males and females and between females from sexual and parthenogenetic populations. We also tested the ability of males to discriminate between sexual and parthenogenetic females in a laboratory bioassay. Our results show that male C. hookeri has morphological traits that facilitate mobility (smaller body with disproportionately longer legs) and mate detection (disproportionately longer antennae), and adult females release significantly higher amounts of volatile organic compounds than males when this species is sexually active, in accordance with their distinctive sex roles. Although some differences were detected between sexual and parthenogenetic females, the latter appear to maintain copulatory behaviors and chemical signaling. Males were unable to distinguish between sexual and parthenogenetic females, suggesting that there has been little decay in the sexual traits in the parthenogenetic lineage of C. hookeri" |
Keywords: | Gc-ms chemical signals male choice morphometrics parthenogenetic reproduction scramble competition sexual reproduction sexual traits; |
Notes: | "PubMed-not-MEDLINENakano, Mari Morgan-Richards, Mary Godfrey, A Jonathan R Clavijo McCormick, Andrea eng -/Orthopterists' Society/ -/George Mason Charitable Trust/ Switzerland 2019/07/13 Insects. 2019 Jul 10; 10(7):202. doi: 10.3390/insects10070202" |