Safeguarding Tortoises: Diapause and Biobanking for Conservation

Endangered Burmese Star Tortoise

Tortoises lack sex chromosomes; instead, their sex is determined by the temperature at which their eggs are incubated. As climate change affects environmental temperatures, tortoise sex ratios are increasingly imbalanced, placing these ancient species at risk. Moving beyond the mammalian model, this project seeks to elucidate the mechanisms of embryonic diapause in tortoises to improve incubation protocols, focusing on the endangered Burmese star tortoise and the radiated tortoise.

By leveraging the unique process of embryonic diapause, the project aims to uncover novel insights into reproductive timing and resilience under shifting climatic conditions. This cross-continental team will collaborate with Revive & Restore’s Biotechnology for Bird Conservation P.I., Dr. Guojun Sheng, to isolate and culture germline stem cells, known as primordial germ cells, from tortoise embryos. This will enable the development of in vitro models to study both diapause and temperature-dependent sex determination (TSD). In partnership with Prague Zoo, Plzeň Zoo, and Turtle Island, the project will generate optimised and standardised incubation protocols aimed at increasing hatch success and restoring balanced, healthy sex ratios in captive breeding programs.