Johan A. A. Nylander
Publications (Showing 2 of 2)
An evaluation of new parsimony-based versus parametric inference methods in biogeography: a case study using the globally distributed plant family Sapindaceae
Journal of Biogeography
2010
Vol. 38, Issue 3
pp. 531-550
Aim Recently developed parametric methods in historical biogeography allow researchers to integrate temporal and palaeogeographical information into the reconstruction of biogeographical scenarios, thus overcoming a known bias of parsimony-based approaches. Here, we compare a parametric method, dispersal–extinction–cladogenesis (DEC), against a parsimony-based method, dispersal–vicariance analysis (DIVA), which does not incorporate branch lengths but accounts for phylogenetic uncertainty through a Bayesian empirical approach (Bayes-DIVA). We analyse the benefits and limitations of each method using the cosmopolitan plant family Sapindaceae as a case study.
Location World-wide.
Methods Phylogenetic relationships were estimated by Bayesian inference on a large dataset representing generic diversity within Sapindaceae. Lineage divergence times were estimated by penalized likelihood over a sample of trees from the posterior distribution of the phylogeny to account for dating uncertainty in biogeographical reconstructions. We compared biogeographical scenarios between Bayes-DIVA and two different DEC models: one with no geological constraints and another that employed a stratified palaeogeographical model in which dispersal rates were scaled according to area connectivity across four time slices, reflecting the changing continental configuration over the last 110 million years.
Results Despite differences in the underlying biogeographical model, Bayes-DIVA and DEC inferred similar biogeographical scenarios. The main differences were: (1) in the timing of dispersal events – which in Bayes-DIVA sometimes conflicts with palaeogeographical information, and (2) in the lower frequency of terminal dispersal events inferred by DEC. Uncertainty in divergence time estimations influenced both the inference of ancestral ranges and the decisiveness with which an area can be assigned to a node.
Main conclusions By considering lineage divergence times, the DEC method gives more accurate reconstructions that are in agreement with palaeogeographical evidence. In contrast, Bayes-DIVA showed the highest decisiveness in unequivocally reconstructing ancestral ranges, probably reflecting its ability to integrate phylogenetic uncertainty. Care should be taken in defining the palaeogeographical model in DEC because of the possibility of overestimating the frequency of extinction events, or of inferring ancestral ranges that are outside the extant species ranges, owing to dispersal constraints enforced by the model. The wide-spanning spatial and temporal model proposed here could prove useful for testing large-scale biogeographical patterns in plants.
DOI:
10.1111/j.1365-2699.2010.02432.x
Plastid and nuclear DNA markers reveal intricate relationships at subfamilial and tribal levels in the soapberry family (Sapindaceae)
Molecular Phylogenetics and Evolution
2009
Vol. 51, Issue 2
pp. 238-258
The economically important soapberry family (Sapindaceae) comprises about 1900 species mainly found in the tropical regions of the world, with only a few genera being restricted to temperate areas. The infrafamilial classification of the Sapindaceae and its relationships to the closely related Aceraceae and Hippocastanaceae – which have now been included in an expanded definition of Sapindaceae (i.e., subfamily Hippocastanoideae) – have been debated for decades. Here we present a phylogenetic analysis of Sapindaceae based on eight DNA sequence regions from the plastid and nuclear genomes and including 85 of the 141 genera defined within the family. Our study comprises 997 new sequences of Sapindaceae from 152 specimens. Despite presenting 18.6% of missing data our complete data set produced a topology fully congruent with the one obtained from a subset without missing data, but including fewer markers. The use of additional information therefore led to a consistent result in the relative position of clades and allowed the definition of a new phylogenetic hypothesis. Our results confirm a high level of paraphyly and polyphyly at the subfamilial and tribal levels and even contest the monophyletic status of several genera. Our study confirms that the Chinese monotypic genus Xanthoceras is sister to the rest of the family, in which subfamily Hippocastanoideae is sister to a clade comprising subfamilies Dodonaeoideae and Sapindoideae. On the basis of the strong support demonstrated in Sapindoideae, Dodonaeoideae and Hippocastanoideae as well as in 14 subclades, we propose and discuss informal groupings as basis for a new classification of Sapindaceae.
DOI:
10.1016/j.ympev.2009.01.012