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ABSTRACT AimFerns are globally distributed, yet the number of studies examining the historical evolution of African taxa is relatively low. Investigation of the evolution of African fern diversity is critical in order to understand patterns and processes that have global relevance (e.g., the pantropical diversity disparity [PDD] pattern). This study aims to examine when and from where a globally distributed fern lineage arrived in sub‐Saharan Africa, to obtain a better understanding of potential processes contributing to patterns of diversity across the region. LocationGlobal, sub‐Saharan Africa. TaxonAsplenium(Aspleniaceae). MethodsWe analysed five loci from 537Aspleniumtaxa using a maximum likelihood (IQ‐Tree) phylogenetic framework. For age estimation, we performed penalised likelihood as implemented in treePL, and executed a Bayesian analysis using BEAST. Biogeographical analyses were carried out using BioGeoBEARS. ResultsMost dispersals into Africa occurred within the last ~55 myr, with the highest diversity of sub‐Saharan African taxa concentrated in two clades, each of which descended from an Asian ancestor. Additional dispersals to sub‐Saharan Africa can be found throughout the phylogeny. Lastly, potential cryptic species diversity exists withinAspleniumas evidenced by several polyphyletic taxa. Main ConclusionsWe recover multiple dispersals ofAspleniumto sub‐Saharan Africa, with two major lineages likely diversifying after arrival.
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Old origin for an European‐African amphitropical disjunction pattern: New insights from a case study on wingless darkling beetles
Abstract AimThe origin of the amphitropic Mediterranean Basin and southern African disjunction (European–African amphitropical disjunction; EAAD) pattern is generally attributed to recent dispersal events. However, our knowledge is limited because the origin of the EAAD pattern has been almost exclusively studied in plants. Here, we investigate the origin of this wide‐ranging disjunction pattern in a group of wingless insects, consisting of two major clades, both of which have EAAD distributions. LocationSub‐Saharan Africa and Mediterranean region. TaxonTribe Dendarini (Coleoptera: Tenebrionidae). MethodsWe reconstructed a dated molecular phylogeny of major lineages within Dendarini using maximum likelihood and Bayesian inference. The employed dataset included sequences of six genes (two mitochondrial and four nuclear fragments) generated for 72 species. To investigate the sequence and timing leading to present‐day wide‐ranging disjunction patterns, we conducted parametric historical biogeography analyses. ResultsThe dated phylogenetic framework supports the monophyly of all major Dendarini lineages and highlights the origin of the tribe in sub‐Saharan Africa during the Middle Eocene. From there, representatives of the two major lineages colonized the Mediterranean region at the Oligocene‐Miocene boundary, with one lineage first reaching North Africa, whilst the other reached southern Europe. Main conclusionsThe origin of the EAAD in Dendarini beetles is ancient and better explained by the progressive fragmentation of the pan‐African rainforest that started in the Early Eocene than by other scenarios. This and the increased aridification associated with the global long‐term cooling trend that took place at that time had a strong influence on the diversification and distribution of xerophilic organisms such as dendarine beetles. This challenges the understanding of the origin of EAAD patterns, highlighting that they do not only result from recent dispersal events between the Pliocene and Pleistocene.
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- Award ID(s):
- 2009247
- PAR ID:
- 10445268
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Biogeography
- Volume:
- 49
- Issue:
- 1
- ISSN:
- 0305-0270
- Page Range / eLocation ID:
- p. 130-141
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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