THERMAL VULNERABILITY OF THREE CAATINGA LIZARDS IN FUTURE CLIMATE CHANGE SCENARIOS

• Grant number: 25/06645-0
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: December 01, 2025
• End date: November 30, 2028
• Field of knowledge: Biological Sciences - Zoology - Physiology of Recent Groups
• Principal Investigator: Carlos Arturo Navas Iannini
• Grantee: Patricia Marques do Amaral Oliveira
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Climate change poses significant challenges for ectothermic organisms, such as lizards, especially in arid environments like the Caatinga. This study will investigate the thermal vulnerability of Caatinga lizards through the critical thermal maximum (CTmax), a fundamental indicator of heat tolerance. Three species with different ecological patterns and microhabitat use will be analyzed: Tropidurus cocorobensis, Ameivula ocellifera, and Phyllopezus pollicaris. The experiment will consist of the gradual heating of individuals until thermal failure, using the loss of righting reflex (LOE) as the failure criterion. Data will be analyzed using the Thermal Death Time (TDT) model, which relates temperature and time until thermal failure, allowing the estimation of the thermal resistance factor (z) and comparisons between species. Additionally, we will use climatic data from WorldClim v.2.1 to assess current environmental conditions (1970-2000) and future projections (2081-2100), based on the average of eight general circulation models (GCMs), enabling predictions of the potential impacts of global warming on the species' thermal distribution. The results will contribute to understanding these lizards' thermal resilience and aid in formulating conservation strategies in response to climate change. The dissemination of results will occur through publications in high-impact scientific journals, technical reports, and environmental education initiatives in collaboration with local communities and conservation institutions, aiming to raise awareness of the importance of Caatinga herpetofauna.