Get access

Exploring the origin of the latitudinal diversity gradient: Contrasting the sister fern genera Phegopteris and Pseudophegopteris

Authors

  • Harald SCHNEIDER,

    Corresponding author
    1. Department of Life Sciences, Natural History Museum, London SW7 5BD, UK
    • State Key Laboratory of Systematic and Evolutionary Biology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    Search for more papers by this author
  • Li-Juan HE,

    1. State Key Laboratory of Systematic and Evolutionary Biology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    2. Graduate University of Chinese Academy of Sciences, Beijing 100049, China
    Search for more papers by this author
  • Jeannine MARQUARDT,

    1. Department of Life Sciences, Natural History Museum, London SW7 5BD, UK
    Search for more papers by this author
  • Li WANG,

    1. State Key Laboratory of Systematic and Evolutionary Biology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    2. Department of Life Sciences, Natural History Museum, London SW7 5BD, UK
    3. Graduate University of Chinese Academy of Sciences, Beijing 100049, China
    Search for more papers by this author
  • Jochen HEINRICHS,

    1. Department of Systematic Botany, Albrecht-von-Haller Institute of Plant Sciences, Georg-August-University, 37073 Göttingen, Germany
    Search for more papers by this author
  • Sabine HENNEQUIN,

    1. UMR 7207 UPMC CNRS MNHN ‘Centre de recherche sur la Paléobiodiversité et les Paléoenvironnements’, 43 rue de Buffon, 75005 Paris, France
    Search for more papers by this author
  • Xian-Chun ZHANG

    1. State Key Laboratory of Systematic and Evolutionary Biology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    Search for more papers by this author

Author for correspondence. E-mail: h.schneider@nhm.ac.uk. Tel.: 44-20-79426058. Fax: 44-20-79425501.

Abstract

The origin of the latitudinal biodiversity gradient has been studied using various approaches. Here, we employ a comparative phylogenetic approach to infer evidence for the hypothesis that differences in diversification rates are one of the main factors contributing to the assembly of this gradient. We infer the phylogeny of the two sister genera Phegopteris and Pseudophegopteris. The two genera are distinct in their species richness (4 vs. 20 spp.) and their preferences to temperate to subtropical (Phegopteris) or tropical climates (Pseudophegopteris). Using sequences of three plastid DNA regions, we confirm the monophyly of each genus and infer the inter- and intra-generic phylogenetic differentiation of the sister clades. We recover evidence for distinct net-diversification rate between the two genera, which may be caused either by a higher extinction risk of temperate Phegopteris or a higher speciation rate of tropical Pseudophegopteris. We discuss our results in the context of our current knowledge on the speciation processes of ferns. We conclude on the crucial influence of other factors such as the rise of the Himalaya on the diversification of these ferns.

Ancillary