Sexual selection after gamete release in broadcast spawning invertebrates

Area of Science:

• Evolutionary biology
• Reproductive biology
• Animal behavior

Background:

• Broadcast spawning invertebrates exhibit external fertilization, an ancestral reproductive strategy.
• This strategy allows for the study of sexual selection acting after gamete release.
• These systems are valuable for understanding the evolution of sexual reproduction.

Purpose of the Study:

• To synthesize progress in understanding sperm competition and sexual selection in broadcast spawners.
• To highlight the potential of these models for evolutionary and mechanistic insights.
• To test and extend classic theories of sexual selection.

Main Methods:

• Review and synthesis of existing research on broadcast spawning invertebrates.
• Analysis of sexual selection dynamics in external fertilization systems.
• Comparative approach across diverse invertebrate taxa.

Main Results:

• Broadcast spawners are highly tractable models for sperm competition and gamete-level mate choice.
• Sexual selection strength and direction can vary considerably due to dynamic reproductive conditions.
• These systems offer insights into the evolution of sexual reproduction and sexual conflict.

Conclusions:

• Broadcast spawning invertebrates provide unique opportunities to study gamete-level sexual selection.
• Further research can enhance our understanding of evolutionary processes in sexual reproduction.
• These models are crucial for challenging and extending contemporary theories in sexual selection.