A Southern Hemisphere origin for campanulid angiosperms, with traces of the break-up of Gondwana

Abstract

BackgroundNew powerful biogeographic methods have focused attention on long-standing hypotheses regarding the influence of the break-up of Gondwana on the biogeography of Southern Hemisphere plant groups. Studies to date have often concluded that these groups are too young to have been influenced by these ancient continental movements. Here we examine a much larger and older angiosperm clade, the Campanulidae, and infer its biogeographic history by combining Bayesian divergence time information with a likelihood-based biogeographic model focused on the Gondwanan landmasses.ResultsOur analyses imply that campanulids likely originated in the middle Albian (~105 Ma), and that a substantial portion of the early evolutionary history of campanulids took place in the Southern Hemisphere, despite their greater species richness in the Northern Hemisphere today. We also discovered several disjunctions that show biogeographic and temporal correspondence with the break-up of Gondwana.ConclusionsWhile it is possible to discern traces of the break-up of Gondwana in clades that are old enough, it will generally be difficult to be confident in continental movement as the prime cause of geographic disjunctions. This follows from the need for the geographic disjunction, the inferred biogeographic scenario, and the dating of the lineage splitting events to be consistent with the causal hypothesis.

A well-sampled phylogenetic analysis of the polystichoid ferns (Dryopteridaceae) suggests a complex biogeographical history involving both boreotropical migrations and recent transoceanic dispersals

“…The biogeographical matrix is presented in Appendix 1. Ancestral area reconstruction (AAR) was done using two different methods: S-DIVA (Yu et al, 2010), and Dispersal-Extinction-Cla dogenesis (hereafter DEC; Beaulieu et al, 2013;Ree et al, 2005;Ree and Smith, 2008;Yu et al, 2013).…”

“…The paleogeographical model (i.e., Q-matrix) is presented in Appendix 2. To account for dating and phylogenetic uncertainties, we used a modified version of the DEC analysis (hereafter S-DEC) described by Beaulieu et al (2013) and implemented in RASP 3.0 (Yu et al, 2013). S-DEC inferred AARs over 100 trees random post-burnin trees from the BEAST analysis.…”

“…S-DEC inferred AARs over 100 trees random post-burnin trees from the BEAST analysis. Then biogeographic reconstructions across these 100 trees were summarized using a composite Akaike weight (Beaulieu et al, 2013) and trace on the MCC BEAST tree.…”

A living fossil tale of Pangaean biogeography

“…The recent biogeographic literature has swarmed with examples refuting the role of continental split in shaping the current patterns of species distribution, but this might simply be a result of the following factors. As recently noted by Beauliey et al [6], most biogeographic studies addressing the question of continental vicariance are based on low-level taxonomic groups (such as genera or families) exhibiting a particular disjunction pattern. In those cases, the inferred dispersal scenario is simply a consequence of the group not being old enough to be influenced by tectonic movement in the first place.…”

Anatomía comparada de la madera de Cupressaceae y su correspondencia con los estudios de filogenia

“…En este escenario, las angiospermas no son lo suficientemente antiguas para verse influenciadas por la deriva continental (Beaulieu et al 2013), empleando para ello coníferas. Debido a su antigüedad, la distribución de las coníferas se ha visto fuertemente influencia por eventos como la deriva continental o los procesos del cambio climático.…”