Biogeography, diversification, and evolution of snakes in the Neotropical region

• Grant number: 22/05543-1
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: October 01, 2022
• End date: August 31, 2026
• Field of knowledge: Biological Sciences - Ecology
• Principal Investigator: Ricardo Jannini Sawaya
• Grantee: Matheus Pontes Nogueira
• Host Institution: Centro de Ciências Naturais e Humanas (CCNH). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil
• Associated research grant: 20/12658-4 - Challenges to the conservation of amphibians and squamate reptiles, with emphasis on the Brazilian fauna: from basic information to conservation actions, AP.BTA.TEM
• Associated scholarship(s): 23/06676-8 - Biogeography, evolution and diversification of vipers through modifications in New World habitat types, BE.EP.DR

Abstract

Snakes are interesting models for biogeographical studies due to their morphological characteristics and widegeographical distribution. The families Viperidae (~370 species) and Dipsadidae (~810 species) occur in both theOld and New World. They occupy different ecological niches, habitats, latitudes, and altitudes, being, therefore,ideal models for biogeographical studies in these regions. Currently, there are two competing hypotheses for theemergence of the Isthmus of Panama, one that supports its emergence about three million years ago and theother about 10 million years ago. Another event that must have significantly affected biodiversity was theformation of the diagonal of open vegetation in South America, which must have acted as a vicariant process forseveral forest species. We propose to analyze the influence of different biogeographical processes (dispersal,vicariance, and extinction) and landscape evolution in South America in order to: 1) analyze the diversification ofviperid snakes from the dynamics of the geographic distributions of their species and their hypothetical ancestorsthroughout of time; 2) test the competing hypotheses about the emergence ages of the Isthmus of Panama fromstudies of comparative phylogeography of viperid and dipsadid snakes; 3) test the hypothesis that vicarianceprocesses were generated by the emergence of the South American diagonal of open vegetation; and 4) testwhether the snakes' body size affected their diversification and biogeography. This project will significantlycontribute to a better understanding of the influence of biogeographical processes and body size on the evolutionof snakes in the Neotropical Region, which has the greatest diversity of vertebrates on the planet.