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Sex Determination, Sexual Development, and Sex Change in Slipper Snails.
Maryna P Lesoway1, Jonathan Q Henry2
1Department of Cell and Developmental Biology, University of Illinois, Urbana-Champaign, Urbana, IL, USA.
Results and Problems in Cell Differentiation
|October 11, 2019
Summary
Calyptraeid gastropods, or slipper snails, offer a unique model for studying sequential hermaphroditism. Social cues influence their sex change timing, but the underlying mechanisms require further investigation.
Area of Science:
- Evolutionary Biology
- Developmental Biology
- Marine Biology
Background:
- Sexual development exhibits significant diversity across taxa, with hermaphroditism being widespread despite dioecy being the norm in animals.
- Current understanding of sexual development relies heavily on a few model systems, limiting broader evolutionary conclusions.
- Calyptraeid gastropods, marine snails, are sequential hermaphrodites (protandrous) that transition from male to female, offering a valuable model for studying sex determination evolution.
Purpose of the Study:
- To review current knowledge on sexual development and sex determination in calyptraeid gastropods and other molluscs.
- To highlight factors influencing the timing of sex change and explore potential underlying mechanisms.
- To consider the embryonic origins of the germ line and the impact of environmental contaminants on sexual development.
Main Methods:
- Review of existing literature on calyptraeid gastropods and molluscan sexual development.
- Analysis of environmental and social factors influencing sex change timing in sequential hermaphrodites.
- Examination of germ line development and the effects of environmental contaminants.
Main Results:
- Sex change in calyptraeids is typically environmentally controlled, often mediated by social interactions.
- Males in proximity to females delay sex change, transitioning at larger sizes, while isolated males change sex earlier and at smaller sizes.
- The precise molecular and developmental mechanisms controlling this environmentally induced sex change remain poorly understood.
Conclusions:
- Calyptraeid gastropods provide a powerful model system for investigating the evolution of sex determination in sequentially hermaphroditic species.
- Understanding the mechanisms of sex change in these snails can offer insights into broader principles of sexual development and evolution.
- Further research is needed to elucidate the molecular pathways and environmental triggers governing sex determination and development in molluscs.
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