Recent lineage diversification in a venomous snake through dispersal across the Amazon River

Author(s)

Gibbs, H. Lisle ^{[1, 2]} ; Sovic, Michael ^[1] ; Amazonas, Diana ^[3] ; Chalkidis, Hippocrates ^[4] ; Salazar-Valenzuela, David ^[5] ; Moura-Da-Silva, Ana M. ^[3]

Affiliation

^[1] Ohio State Univ, Dept Evolut Ecol & Organismal Biol, Columbus, OH 43210 - USA

^[2] Ohio State Univ, Ohio Biodivers Conservat Partnership, Columbus, OH 43210 - USA

^[3] Inst Butantan, Lab Imunopatol, Sao Paulo - Brazil

^[4] Fac Integradas Tapajos, Santarem, Para - Brazil

^[5] Univ Tecnol Indoamer, Ctr Invest Biodiversidad & Cambio Climat, Quito - Ecuador

• Document type: Journal article
• Source: Biological Journal of the Linnean Society; v. 123, n. 3, p. 651-665, MAR 2018.
• Web of Science Citations: 6

Abstract

Identifying the evolutionary and ecological mechanisms that drive lineage diversification in the species-rich tropics is of broad interest to evolutionary biologists. Here, we use phylogeographical and demographic analyses of genome-scale RADseq data to assess the impact of a large geographical feature, the Amazon River, on lineage formation in a venomous pitviper, Bothrops atrox. We compared genetic differentiation in samples from four sites near Santarem, Brazil, that spanned the Amazon and represented major habitat types. A species delimitation analysis identified each population as a distinct evolutionary lineage while a species tree analysis with populations as taxa revealed a phylogenetic tree consistent with dispersal across the Amazon from north to south. Phylogenetic analyses of mitochondrial DNA variation confirmed this pattern and suggest that all lineages originated during the mid- to late Pleistocene. Historical demographic analyses support a population model of lineage formation through isolation between lineages with low ongoing migration between large populations and reject a model of differentiation through isolation by distance alone. The results provide a rare example of a phylogeographical pattern demonstrating dispersal over evolutionary timescales across a large tropical river and suggest a role for the Amazon River as a driver of in situ divergence both by impeding (but not preventing) gene flow and through parapatric differentiation along an ecological gradient. (AU)

• FAPESP's process: 16/50127-5 - Dimensions US-BIOTA São Paulo: scales of biodiversity: integrated studies of snake venom evolution and function across multiple levels of diversity
• Grantee: Inácio de Loiola Meirelles Junqueira de Azevedo
• Support Opportunities: BIOTA-FAPESP Program - Thematic Grants