Dataset Information

Divergence in androgen sensitivity contributes to population differences in sexual dimorphism of electrocommunication behavior.

ABSTRACT: Weakly-electric fish (Apteronotidae) produce highly diverse electrocommunication signals. Electric organ discharges (EODs) vary across species, sexes, and in the magnitude and direction of their sexual dimorphism. Gonadal steroid hormones can modulate EODs, and differences in androgen sensitivity are hypothesized to underlie variation in the degree of sexual dimorphism across species. In this study, we asked whether variation in androgen sensitivity explained variation in sexual dimorphism of EODs within species, at the population level. We examined two populations of black ghost knifefish (Apteronotus albifrons), one from the Orinoco and the other from the Amazon River Basin. EOD frequency (EODf) and chirp rates were measured to characterize diversity in sexual dimorphism across populations. The magnitude of sexual dimorphism in EODf differed significantly across populations, and was more pronounced in the Orinoco population than in the Amazon population. Chirp rates were sexually monomorphic in both populations. 11-Ketotestosterone (11-kT) was administered over a two-week period to assess population differences in sensitivity to androgens. 11-kT masculinized EODf significantly more in the population with the greater degree of sexual dimorphism. 11-kT had no effect on the sexually monomorphic chirping rates. We conclude that population divergence in androgen sensitivity contributes to variation in sexual dimorphism of EODf in A. albifrons.

SUBMITTER: Ho WW

PROVIDER: S-EPMC3570824 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Divergence in androgen sensitivity contributes to population differences in sexual dimorphism of electrocommunication behavior.

Ho Winnie W WW Rack Jessie M JM Smith G Troy GT

Hormones and behavior 20121108 1

Weakly-electric fish (Apteronotidae) produce highly diverse electrocommunication signals. Electric organ discharges (EODs) vary across species, sexes, and in the magnitude and direction of their sexual dimorphism. Gonadal steroid hormones can modulate EODs, and differences in androgen sensitivity are hypothesized to underlie variation in the degree of sexual dimorphism across species. In this study, we asked whether variation in androgen sensitivity explained variation in sexual dimorphism of EO ...[more]

PMID: 23142327

Similar Datasets

Project description:Sexual selection and aerodynamic forces affecting structural properties of the flight feathers of birds are poorly understood. Here, we compared the structural features of the innermost primary wing feather (P1) and the sexually dimorphic outermost (Ta6) and monomorphic second outermost (Ta5) tail feathers of barn swallows (Hirundo rustica) from a Romanian population to investigate how sexual selection and resistance to aerodynamic forces affect structural differences among these feathers. Furthermore, we compared structural properties of Ta6 of barn swallows from six European populations. Finally, we determined the relationship between feather growth bars width (GBW) and the structural properties of tail feathers. The structure of P1 indicates strong resistance against aerodynamic forces, while the narrow rachis, low vane density and low bending stiffness of tail feathers suggest reduced resistance against airflow. The highly elongated Ta6 is characterized by structural modifications such as large rachis width and increased barbule density in relation to the less elongated Ta5, which can be explained by increased length and/or high aerodynamic forces acting at the leading tail edge. However, these changes in Ta6 structure do not allow for full compensation of elongation, as reflected by the reduced bending stiffness of Ta6. Ta6 elongation in males resulted in feathers with reduced resistance, as shown by the low barb density and reduced bending stiffness compared to females. The inconsistency in sexual dimorphism and in change in quality traits of Ta6 among six European populations shows that multiple factors may contribute to shaping population differences. In general, the difference in quality traits between tail feathers cannot be explained by the GBW of feathers. Our results show that the material and structural properties of wing and tail feathers of barn swallows change as a result of aerodynamic forces and sexual selection, although the result of these changes can be contrasting.

Project description:To decipher hormonal from chromosomal factors we compared DNA-methylation of 27,568 CpG-loci in genital fibroblasts from 46,XY feminized individuals (AIS) with inactivating androgen receptor mutations to those of normal males. The results of the following two subset comparisons are linked to the Series record below: CpG loci differentially methylated (q<0.04) between AIS and male controls (primary human genital fibroblasts): To decipher hormonal from chromosomal factors we compared DNA-methylation of 27,568 CpG-loci in genital fibroblasts from 46,XY feminized individuals (AIS) with inactivating androgen receptor mutations to those of normal males. Cell culture of primary fibroblasts from scrotum/ labia majora from donors with PAIS (n=13), MAIS (n=1) or CAIS (n=13) and 9 controls were analyzed using the HumanMethylation27 Bead Chip. 13 AIS samples and all controls were analyzed in duplicates. Samples with gene call rates <95% as analyzed with BeadStudio software (Illumina, Inc.) and CpGs with detection p-values >0.05 in at least one experiment were excluded from analyses. 54 hybridizations with 25,988 CpGs entered the analysis. Differential methylation analysis (DMA) was performed based on average beta-values were performed using OMICS Explorer (v.2.1(25); Qlucore, Sweden). This file contains CpG loci found differentially methylated (q<0.04) by this approach. CpG loci characterized by a high varibility in their DNA methylation value in AIS compared to male controls (primary human genital fibroblasts): To decipher hormonal from chromosomal factors we compared DNA-methylation of 27,568 CpG-loci in genital fibroblasts from 46,XY feminized individuals (AIS) with inactivating androgen receptor mutations to those of normal males. Cell culture of primary fibroblasts from scrotum/ labia majora from donors with PAIS (n=13), MAIS (n=1) or CAIS (n=13) and 9 controls were analyzed using the HumanMethylation27 Bead Chip. 13 AIS samples and all controls were analyzed in duplicates. Samples with gene call rates <95% as analyzed with BeadStudio software (Illumina, Inc.) and CpGs with detection p-values >0.05 in at least one experiment were excluded from analyses. 54 hybridizations with 25,988 CpGs entered the analysis. CpG loci with beta-values ranged in control samples up to 0.34 and a difference of the interquartiles between controls and AIS samples above 0.16 were considered as being variably methylated in AIS and are included in this file.

Dataset Information

Divergence in androgen sensitivity contributes to population differences in sexual dimorphism of electrocommunication behavior.

Publications

Divergence in androgen sensitivity contributes to population differences in sexual dimorphism of electrocommunication behavior.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets