loading page

Barriers to gene flow along the Brazilian coast: a synthesis and data analysis
  • +1
  • Nuno Martins,
  • Leonardo Macagnan,
  • Valéria Cassano,
  • CARLOS GURGEL
Nuno Martins
USP
Author Profile
Leonardo Macagnan
Federal University of Santa Catarina
Author Profile
Valéria Cassano
Universidade de São Paulo
Author Profile
CARLOS GURGEL
Universidade Federal de Santa Catarina
Author Profile

Abstract

Barriers to gene flow (BGF) play a pivotal role in the dynamics of population genetics promoting genetic differentiation, thus, are inexorably associated with the development and maintenance of phylogeographic structure. Phylogeographic structure resulting from BGF represents data that help the management of natural genetic resources, aiding in the recognition of areas of conservation interest. Several geographic and oceanographic processes found along the Brazilian coast have been proposed as BGF. However, no consensus exist identifying which of them represents the most important in shaping biodiversity. Therefore, this study provides a synthesis of the scientific literature on Brazilian marine phylogeography and used published data to build datasets that allowed us apply linear (lm) and generalized additive models (gam) to identify spatially congruent phylogeographic breaks among marine species (as areas of high BGF frequency occurrence). Lm identified a significant negative correlation between the occurrence of BGF and latitude, suggesting that population in the tropics are genetically more structured than in higher latitudes. This result bears strong association with the latitude species diversity gradient observed worldwide. Gam identified Cape São Roque (05° 28’ S) as the main BGF for populations with continuous distribution along the Brazilian coast. Cape São Roque is located near the center point region where the South Equatorial Current splits into the northward North Brazil Current and the southward Brazil Current. This study represents the first literature synthesis of Brazil’s marine phylogeography and provides a novel explicit quantitative approach to comparative phylogeography.

Peer review status:UNDER REVIEW

10 Feb 2021Submitted to Molecular Ecology
11 Feb 2021Assigned to Editor
11 Feb 2021Submission Checks Completed
17 Feb 2021Reviewer(s) Assigned