John Smout

Research title: The Genetic and Cellular Basis of Viviparity

Research Summary

My PhD project addresses the genetic and cellular basis of oviparity and viviparity using the common lizard, Zootoca vivipara, as a model for the transition between reprodutive modes in squamates in other amniotes.

The evolution of viviparity from oviparity represents a major innovation in amniote life history, but the cellular and molecular changes that underlie this transition are presently poorly understood. The majority of oviparity-viviparity transitions have occurred in squamate reptiles (snakes, lizards, and their relatives), more than in all other amniote lineages. Z. vivipara is highly unusual as this species is reproductively bimodal, with both oviparous and viviparous lineages, allowing for comparisons between oviparity and viviparity in otherwise genetically similar animals. My research exploits this remarkable model system to study the genetic and cellular foundations of this important evolutionary transition.

Research Aims:

  • Validate candidate genes linked to oviparity and viviparity, using tissue cultures derived from Z. vivipara primary oviduct cells
  • Investigate the cellular basis of oviparity and viviparity, using single-cell RNA sequencing of Z. vivipara reproductive tissue
  • Investigate the molecular evolution of oviparity and viviparity across squamates, by analysing shifts in selection in different taxa which have undergone oviparity-viviparity transitions