Androgenic signaling systems and their role in behavioral evolution

Area of Science:

• Evolutionary biology
• Endocrinology
• Animal behavior

Background:

• Sex steroids influence reproductive phenotypes across vertebrates.
• The effects and mechanisms of sex steroid action vary significantly, even among related species.
• Understanding this variation is key to explaining the diversity of sexual traits.

Purpose of the Study:

• Introduce the Evolutionary Potential Hypothesis for androgen-dependent reproductive behavior evolution.
• Shift focus from circulating steroid levels to molecular mechanisms of hormone action.
• Provide empirical data on co-factors as evolutionary substrates.

Main Methods:

• Literature review and hypothesis framework development.
• Presentation of new empirical data on androgen action modulators.
• Case study analysis of the golden-collared manakin (Manacus vitellinus).

Main Results:

• The Evolutionary Potential Hypothesis posits that cellular mechanisms of androgen action evolve independently.
• Evolution acts on molecular components like co-factors, leading to diverse signaling pathways.
• In manakins, androgen signaling in skeletal muscle enhances courtship display motor performance.

Conclusions:

• Molecular mechanisms of androgen action provide a flexible substrate for the evolution of reproductive behaviors.
• Focusing on cellular mechanisms offers a more comprehensive understanding of steroid-dependent trait evolution.
• This framework aids in understanding the diversification of complex animal behaviors.