Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal. (29th November 2013)

• Record Type: Journal Article
• Authors: Korall, Petra; Pryer, Kathleen M.; Parmakelis, Aristeidis
• Is Part Of: Journal of biogeography. Volume 41:Number 2(2014:Feb.)
• Page Start: 402
• Page End: 413
• Publication Date: 2013-11-29
• Subjects: Biogeography -- Periodicals; 578.09
• DOI: 10.1111/jbi.12222
• Languages: English
• ISSNs: 0305-0270

Abstract

<abstract abstract-type="main" id="jbi12222-abs-0001"> <title>ABSTRACT</title> <sec id="jbi12222-sec-0001" sec-type="section"> <title>Aim</title> <p>Scaly tree ferns, Cyatheaceae, are a well‐supported group of mostly tree‐forming ferns found throughout the tropics, the subtropics and the south‐temperate zone. Fossil evidence shows that the lineage originated in the Late Jurassic period. We reconstructed large‐scale historical biogeographical patterns of Cyatheaceae and tested the hypothesis that some of the observed distribution patterns are in fact compatible, in time and space, with a vicariance scenario related to the break‐up of Gondwana.</p> </sec> <sec id="jbi12222-sec-0002" sec-type="section"> <title>Location</title> <p>Tropics, subtropics and south‐temperate areas of the world.</p> </sec> <sec id="jbi12222-sec-0003" sec-type="section"> <title>Methods</title> <p>The historical biogeography of Cyatheaceae was analysed in a maximum likelihood framework using <sc>Lagrange</sc>. The 78 ingroup taxa are representative of the geographical distribution of the entire family. The phylogenies that served as a basis for the analyses were obtained by Bayesian inference analyses of mainly previously published DNA sequence data using <sc>MrBayes</sc>. Lineage divergence dates were estimated in a Bayesian Markov chain Monte Carlo framework using <sc>beast</sc>.</p> </sec> <sec id="jbi12222-sec-0004" sec-type="section"> <title>Results</title> <p>Cyatheaceae originated in the Late Jurassic in either South America or Australasia. Following a range expansion, the ancestral distribution of the marginate‐scaled clade included both these areas, whereas <italic>Sphaeropteris</italic> is reconstructed as having its origin only in Australasia. Within the marginate‐scaled clade, reconstructions of early divergences are hampered by the unresolved relationships among the <italic>Alsophila</italic>, <italic> Cyathea</italic> and <italic>Gymnosphaera</italic> lineages. Nevertheless, it is clear that the occurrence of the <italic>Cyathea</italic> and <italic>Sphaeropteris</italic> lineages in South America may be related to vicariance, whereas transoceanic dispersal needs to be inferred for the range shifts seen in <italic>Alsophila</italic> and <italic>Gymnosphaera</italic>.</p> </sec> <sec id="jbi12222-sec-0005" sec-type="section"> <title>Main conclusions</title> <p>The evolutionary history of Cyatheaceae involves both Gondwanan vicariance scenarios as well as long‐distance dispersal events. The number of transoceanic dispersals reconstructed for the family is rather few when compared with other fern lineages. We suggest that a causal relationship between reproductive mode (outcrossing) and dispersal limitations is the most plausible explanation for the pattern observed.</p> </sec> </abstract>