Structure and evolution of the sexually dimorphic integumentary swelling on the hands of dendrobatid poison frogs and their relatives (Amphibia: Anura: Dendrobatoidea)

Androgen-induced plasticity at a “vocal” neuromuscular synapse

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100167895 ◽

1994 ◽

Vol 52 ◽

pp. 32-33

Author(s):

Darcy B. Kelley ◽

Martha L. Tobias ◽

Mark Ellisman

Keyword(s):

Xenopus Laevis ◽

Motor Neurons ◽

Sexual Differentiation ◽

Molecular Basis ◽

Neuromuscular Synapse ◽

Sexually Dimorphic ◽

Intracellular Protein ◽

Developmental Program ◽

Androgen Action ◽

Clawed Frog

Brain and muscle are sexually differentiated tissues in which masculinization is controlled by the secretion of androgens from the testes. Sensitivity to androgen is conferred by the expression of an intracellular protein, the androgen receptor. A central problem of sexual differentiation is thus to understand the cellular and molecular basis of androgen action. We do not understand how hormone occupancy of a receptor translates into an alteration in the developmental program of the target cell. Our studies on sexual differentiation of brain and muscle in Xenopus laevis are designed to explore the molecular basis of androgen induced sexual differentiation by examining how this hormone controls the masculinization of brain and muscle targets.Our approach to this problem has focused on a highly androgen sensitive, sexually dimorphic neuromuscular system: laryngeal muscles and motor neurons of the clawed frog, Xenopus laevis. We have been studying sex differences at a synapse, the laryngeal neuromuscular junction, which mediates sexually dimorphic vocal behavior in Xenopus laevis frogs.

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The Relationship of Digit Ratio (2D:4D) and Gender-Role Orientation in Four National Samples

Journal of Individual Differences ◽

10.1027/1614-0001.28.2.78 ◽

2007 ◽

Vol 28 (2) ◽

pp. 78-87 ◽

Cited By ~ 12

Author(s):

Stefan J. Troche ◽

Nina Weber ◽

Karina Hennigs ◽

Carl-René Andresen ◽

Thomas H. Rammsayer

Keyword(s):

Gender Role ◽

Sex Role ◽

Role Orientation ◽

Sexually Dimorphic ◽

Gender Role Orientation ◽

Left Hand ◽

Fourth Finger ◽

And Gender ◽

Relationship Of ◽

The Relationship

Abstract. The ratio of second to fourth finger length (2D:4D ratio) is sexually dimorphic with women having higher 2D:4D ratio than men. Recent studies on the relationship between 2D:4D ratio and gender-role orientation yielded rather inconsistent results. The present study examines the moderating influence of nationality on the relationship between 2D:4D ratio and gender-role orientation, as assessed with the Bem Sex-Role Inventory, as a possible explanation for these inconsistencies. Participants were 176 female and 171 male university students from Germany, Italy, Spain, and Sweden ranging in age from 19 to 32 years. Left-hand 2D:4D ratio was significantly lower in men than in women across all nationalities. Right-hand 2D:4D ratio differed only between Swedish males and females indicating that nationality might effectively moderate the sexual dimorphism of 2D:4D ratio. In none of the examined nationalities was a reliable relationship between 2D:4D ratio and gender-role orientation obtained. Thus, the assumption of nationality-related between-population differences does not seem to account for the inconsistent results on the relationship between 2D:4D ratio and gender-role orientation.

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