Get access

The genetic effects of Late Quaternary climatic changes over a tropical latitudinal gradient: diversification of an Atlantic Forest passerine

Authors

  • FERNANDO M. D’HORTA,

    1. Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, 05508-090 São Paulo, SP, Brazil
    Search for more papers by this author
  • GUSTAVO S. CABANNE,

    1. Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, 05508-090 São Paulo, SP, Brazil
    2. División de Ornitología, Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”, Ángel Gallardo 470, Ciudad de Buenos Aires (C1405DJR), Argentina
    Search for more papers by this author
  • DIOGO MEYER,

    1. Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, 05508-090 São Paulo, SP, Brazil
    Search for more papers by this author
  • CRISTINA Y. MIYAKI

    1. Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, 05508-090 São Paulo, SP, Brazil
    Search for more papers by this author

Fernando Mendonça d’Horta, Fax: +55 +11 30917553; E-mail: fmhorta@usp.br

Abstract

The increase in biodiversity from high to low latitudes is a widely recognized biogeographical pattern. According to the latitudinal gradient hypothesis (LGH), this pattern was shaped by differential effects of Late Quaternary climatic changes across a latitudinal gradient. Here, we evaluate the effects of climatic changes across a tropical latitudinal gradient and its implications to diversification of an Atlantic Forest (AF) endemic passerine. We studied the intraspecific diversification and historical demography of Sclerurus scansor, based on mitochondrial (ND2, ND3 and cytb) and nuclear (FIB7) gene sequences. Phylogenetic analyses recovered three well-supported clades associated with distinct latitudinal zones. Coalescent-based methods were applied to estimate divergence times and changes in effective population sizes. Estimates of divergence times indicate that intraspecific diversification took place during Middle–Late Pleistocene. Distinct demographic scenarios were identified, with the southern lineage exhibiting a clear signature of demographic expansion, while the central one remained more stable. The northern lineage, contrasting with LGH predictions, exhibited a clear sign of a recent bottleneck. Our results suggest that different AF regions reacted distinctly, even in opposite ways, under the same climatic period, producing simultaneously favourable scenarios for isolation and contact among populations.

Ancillary