00430nas a2200145   4500008004100000020001400041245005200055210005000107300001400157490000800171100002100179700002200200700002100222856004100243       2011                        eng d  a0305-736400aDNA barcoding: a new tool for palm taxonomists?0 aDNA barcoding a new tool for palm taxonomists  a1445-14510 v1081 aJeanson, Marc, L1 aLabat, Jean-Noël1 aLittle, Damon, P  uhttps://palms.myspecies.info/node/3702732nas a2200157   4500008004100000020001400041245013100055210006900186300000700255490000600262520220300268100002802471700001802499700001602517856004102533       2011                        eng d  a1741-700700aOrigin and global diversification patterns of tropical rain forests: inferences from a complete genus-level phylogeny of palms0 aOrigin and global diversification patterns of tropical rain fore  a440 v93 aBACKGROUND:Understanding how biodiversity is shaped through time is a fundamental question in biology. Even though tropical rain forests (TRF) represent the most diverse terrestrial biomes on the planet, the timing, location and mechanisms of their diversification remain poorly understood. Molecular phylogenies are valuable tools for exploring these issues, but to date most studies have focused only on recent time scales, which minimizes their explanatory potential. In order to provide a long term view of TRF diversification, we constructed the first complete genus-level dated phylogeny of a largely TRF-restricted plant family with a known history dating back to the Cretaceous. Palms (Arecaceae/Palmae) are one of the most characteristic and ecologically important components of TRF worldwide, and represent a model group for the investigation of TRF evolution.RESULTS:We provide evidence that diversification of extant lineages of palms started during the mid-Cretaceous about 100 million years ago. Ancestral biome and area reconstructions for the whole family strongly support the hypothesis that palms diversified in a TRF-like environment at northern latitudes. Finally, our results suggest that palms conform to a constant diversification model (the 'museum' model or Yule process), at least until the Neogene, with no evidence for any change in diversification rates even through the Cretaceous/Paleogene mass extinction event.CONCLUSIONS:Because palms are restricted to TRF and assuming biome conservatism over time, our results suggest the presence of a TRF-like biome in the mid-Cretaceous of Laurasia, consistent with controversial fossil evidence of the earliest TRF. Throughout its history, the TRF biome is thought to have been highly dynamic and to have fluctuated greatly in extent, but it has persisted even during climatically unfavourable periods. This may have allowed old lineages to survive and contribute to the steady accumulation of diversity over time. In contrast to other plant studies, our results suggest that ancient and steady evolutionary processes dating back to the mid-Cretaceous can contribute, at least in part, to present day species richness in TRF.1 aCouvreur, Thomas, L. P.1 aForest, Felix1 aBaker, W.J.  uhttps://palms.myspecies.info/node/2202866nas a2200241   4500008004100000245007500041210006900116260002200185300001400207490000800221520212900229100002302358700002102381700002402402700002802426700001902454700002002473700002902493700002402522700001802546700002002564856004002584       2011                        eng d00aPhylogenetic relationships among arecoid palms (Arecaceae: Arecoideae)0 aPhylogenetic relationships among arecoid palms Arecaceae Arecoid  cFebruary 16, 2011  a1417-14320 v1083 aBackground and Aims The Arecoideae is the largest and most diverse of the five subfamilies of palms (Arecaceae/Palmae), containing >50 % of the species in the family. Despite its importance, phylogenetic relationships among Arecoideae are poorly understood. Here the most densely sampled phylogenetic analysis of Arecoideae available to date is presented. The results are used to test the current classification of the subfamily and to identify priority areas for future research.Methods DNA sequence data for the low-copy nuclear genes PRK and RPB2 were collected from 190 palm species, covering 103 (96 %) genera of Arecoideae. The data were analysed using the parsimony ratchet, maximum likelihood, and both likelihood and parsimony bootstrapping.Key Results and Conclusions Despite the recovery of paralogues and pseudogenes in a small number of taxa, PRK and RPB2 were both highly informative, producing well-resolved phylogenetic trees with many nodes well supported by bootstrap analyses. Simultaneous analyses of the combined data sets provided additional resolution and support. Two areas of incongruence between PRK and RPB2 were strongly supported by the bootstrap relating to the placement of tribes Chamaedoreeae, Iriarteeae and Reinhardtieae; the causes of this incongruence remain uncertain. The current classification within Arecoideae was strongly supported by the present data. Of the 14 tribes and 14 sub-tribes in the classification, only five sub-tribes from tribe Areceae (Basseliniinae, Linospadicinae, Oncospermatinae, Rhopalostylidinae and Verschaffeltiinae) failed to receive support. Three major higher level clades were strongly supported: (1) the RRC clade (Roystoneeae, Reinhardtieae and Cocoseae), (2) the POS clade (Podococceae, Oranieae and Sclerospermeae) and (3) the core arecoid clade (Areceae, Euterpeae, Geonomateae, Leopoldinieae, Manicarieae and Pelagodoxeae). However, new data sources are required to elucidate ambiguities that remain in phylogenetic relationships among and within the major groups of Arecoideae, as well as within the Areceae, the largest tribe in the palm family.1 aBaker, William, J.1 aNorup, Maria, V.1 aClarkson, James, J.1 aCouvreur, Thomas, L. P.1 aDowe, John, L.1 aLewis, Carl, E.1 aPintaud, Jean-Christophe1 aSavolainen, Vincent1 aWilmot, Tomas1 aChase, Mark, W.  uhttps://palms.myspecies.info/node/8