The role of vicariance and dispersal on the temporal range dynamics of forest vipers in the Neotropical region

PLoS One. 2021 Sep 17;16(9):e0257519. doi: 10.1371/journal.pone.0257519. eCollection 2021.

Abstract

The emergence of the diagonal of open/dry vegetations, including Chaco, Cerrado and Caatinga, is suggested to have acted as a dispersal barrier for terrestrial organisms by fragmenting a single large forest that existed in South America into the present Atlantic and Amazon forests. Here we tested the hypothesis that the expansion of the South American diagonal of open/dry landscapes acted as a vicariant process for forest lanceheads of the genus Bothrops, by analyzing the temporal range dynamics of those snakes. We estimated ancestral geographic ranges of the focal lancehead clade and its sister clade using a Bayesian dated phylogeny and the BioGeoBEARS package. We compared nine Maximum Likelihood models to infer ancestral range probabilities and their related biogeographic processes. The best fitting models (DECTS and DIVALIKETS) recovered the ancestor of our focal clade in the Amazon biogeographic region of northwestern South America. Vicariant processes in two different subclades resulted in disjunct geographic distributions in the Amazon and the Atlantic Forest. Dispersal processes must have occurred mostly within the Amazon and the Atlantic Forest and not between them. Our results suggest the fragmentation of a single ancient large forest into the Atlantic and Amazon forests acting as a driver of vicariant processes for the snake lineage studied, highlighting the importance of the diagonal of open/dry landscapes in shaping distribution patterns of terrestrial biota in South America.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bayes Theorem
  • Bothrops / classification
  • Bothrops / physiology*
  • Forests
  • Phylogeny
  • Phylogeography
  • Population Dynamics
  • South America
  • Tropical Climate

Grants and funding

MPN was granted by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP; https://fapesp.br/) with the grant numbers Proc. 2014/23677-9 and Proc. 2017/11796-1. RJS was granted by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP; https://fapesp.br/) with the grant number proc. 2014/23677-9 and by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq; https://www.gov.br/cnpq/pt-br) with the grant number 312795/2018-1. MM was granted by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP; https://fapesp.br/) with the grant number proc. 2018/14091-1 and by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq; https://www.gov.br/cnpq/pt-br) with the grant number 306961/2015-6. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.