The role of rivers as barriers in the evolution of neotropical biodiversity - a multi-taxon approach based on coalescent models

• Grant number: 24/06959-2
• Support Opportunities: Scholarships in Brazil - Master
• Start date: October 01, 2024
• End date: September 30, 2026
• Field of knowledge: Biological Sciences - Genetics
• Principal Investigator: Isabel Aparecida da Silva Bonatelli
• Grantee: João Roberto Fentanes Machado
• Host Institution: Instituto de Ciências Ambientais, Químicas e Farmacêuticas (ICAQF). Universidade Federal de São Paulo (UNIFESP). Campus Diadema. Diadema , SP, Brazil

Abstract

The hypothesis of rivers as barriers is a classic explanation for the origin and maintenance of high diversity in various ecosystems of the Neotropical region. However, the incorporation of analyses describing shared evolutionary patterns among co-distributed species is still scarce. Studies testing simultaneous divergence among multiple taxa and including abiotic and biotic variables as predictors of contrasting evolutionary responses in population structuring are rare. In this study, comparative phylogeography analyses will be combined with a machine learning predictive approach to investigate the existence of synchronous divergence events among species/populations showing evidence of phylogeographic breaks consistent with the presence of rivers. The main objective of this study is to test the synchronicity of evolutionary divergences among species distributed on opposite sides of three Neotropical rivers that are among the most cited in the literature (Amazonas, Doce, and São Francisco). The work consists of five main activities: (i) obtaining genetic data available in public repositories for species whose diversification seems to have been impacted by the presence of rivers; (ii) inference of species genetic structure and validation of rivers as barriers to gene flow; (iii) testing demographic isolation and migration models; (iv) testing co-divergence; and (v) identifying predictor variables of the role of rivers as barriers. The results should enhance understanding of demographic responses observed in species of the Neotropical region, especially regarding the structural influence of rivers on taxa.