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Published on: March 8, 2020
Viviparity and temperature-dependent sex determination
1School of Animal Biology, University of Western Australia, Crawley, WA, Australia. krobert @ cyllene.uwa.edu.au
Summary
Temperature-dependent sex determination (TSD) is now found in viviparous reptiles, challenging previous theories. Differential maternal basking in these species influences offspring sex ratios.
Area of Science:
- Herpetology
- Evolutionary Biology
- Reproductive Biology
Background:
- Temperature-dependent sex determination (TSD) is a well-studied phenomenon in reptiles.
- TSD was previously thought unlikely in viviparous (live-bearing) taxa due to stable developmental temperatures achieved through maternal basking.
- Recent discoveries have identified TSD in viviparous squamates, challenging these long-held assumptions.
Purpose of the Study:
- To explore the recent discovery and implications of TSD in viviparous reptiles.
- To investigate the mechanisms and adaptive significance of TSD in live-bearing squamates.
- To highlight the need for further research into TSD in a diverse range of viviparous species.
Main Methods:
- The abstract does not detail specific experimental methods.
- It synthesizes existing knowledge and identifies gaps in current understanding.
- Focuses on observational data and theoretical considerations regarding viviparity and TSD.
Main Results:
- TSD has been recently discovered in three species of viviparous skinks.
- Pregnant viviparous females exhibit differential body temperature selection compared to non-pregnant individuals, influencing offspring sex.
- The physiological mechanisms underlying TSD in viviparous reptiles remain largely unknown.
Conclusions:
- The occurrence of TSD in viviparous species requires further investigation across a broader phylogenetic range.
- Understanding the role of sex steroid hormones and in utero manipulation is crucial.
- Fast-maturing squamate reptiles offer a valuable model system for studying the adaptive significance of TSD.
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