title: Androgenic control of male-typical behavior, morphology and sex recognition is independent of the mode of sex determination: A case study on Lichtenfelder's gecko (Eublepharidae: Goniurosaurus lichtenfelderi).
abstract: Previous work on lizards has shown that many sexually dimorphic traits depend on testosterone (T), but the details of this control can vary among species. Here, we tested the role of T on the expression of morphological, physiological, and behavioral traits in Lichtenfelder's gecko (Goniurosaurus lichtenfelderi), from the lizard family Eublepharidae notable for interspecific variation in sexually dimorphic traits and the mode of sex determination. Experiments included three groups of males (intact control, surgically castrated, castrated with T replacement) and two groups of females (intact control, T supplemented). In males, castration caused reductions in 1) the size of hemipenes, 2) offensive aggression, 3) male sexual behavior in a neutral arena, 4) activity of precloacal glands, and 5) loss of male chemical cues for sex recognition. These reductions were not observed in castrated males with T replacement. Interestingly, castrated males performed sexual behavior in their home cages, which shows that the effect of T depends on the environmental context. Notably, tail vibration, previously reported as a courtship behavior in other eublepharids, is displayed by males of G. lichtenfelderi during interactions with conspecifics of both sexes, suggesting an evolutionary shift in the meaning of this signal. In females, T induced growth of hemipenes and male-typical courtship but did not induce precloacal pore activity, aggression, or mounting. In comparison to previous reports on Eublepharis macularius, our results indicate that effects of T do not depend on the mode of sex determination. Further, our results extend our understanding of the complexity of control of male traits and illustrate how lability in the effects of T can be a general mechanism causing evolutionary changes in the components of suites of functionally correlated traits.
authors.affiliation: Graduate Program in Endocrinology and Animal Biosciences, Rutgers University, 84 Lipman Drive, New Brunswick, NJ 08901, USA.
authors.forename: Alison
authors.initials: A
authors.lastname: Golinski
authors.affiliation: Faculty of Science, Charles University in Prague, Department of Ecology, Viničná 7, 128 44 Praha 2, Czech Republic.
authors.forename: Lukáš
authors.initials: L
authors.lastname: Kubička
authors.affiliation: Department of Ecology, Evolution, and Natural Resources, Rutgers University, 14 College Farm Road, New Brunswick, NJ 08901, USA.
authors.forename: Henry
authors.initials: H
authors.lastname: John-Alder
authors.affiliation: Faculty of Science, Charles University in Prague, Department of Ecology, Viničná 7, 128 44 Praha 2, Czech Republic. Electronic address: lukas.kratochvil@natur.cuni.cz.
authors.forename: Lukáš
authors.initials: L
authors.lastname: Kratochvíl
mesh_terms: D000374:Aggression / Q000502:physiology; D000728:Androgens / Q000494:pharmacology / Q000502:physiology*; D000818:Animals; D002369:Castration; D003380:Courtship; D005260:Female; D008116:Lizards / Q000502:physiology*; D008297:Male; D012727:Sex Characteristics; D019849:Sex Determination Processes / Q000187:drug effects / Q000502:physiology*; D012737:Sex Factors; D012726:Sexual Behavior, Animal / Q000187:drug effects / Q000502:physiology*; D013739:Testosterone / Q000494:pharmacology / Q000502:physiology*
chemical_list: D000728:Androgens; D013739:Testosterone
keywords: Aggressive behavior; Androgens; Eublepharis macularius; Lizard; Pore secretions; Sex recognition; Sexual behavior; Sexual dimorphism; Signal evolution