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Pleistocene changes in the flora of the high tropical Andes
Geological data show that high Andean habitats have been available for plant colonization only since the end of the Tertiary. The manner in which plant species moved into these habitats, the timesExpand
The Phylogeny of Linum and Linaceae Subfamily Linoideae, with Implications for Their Systematics, Biogeography, and Evolution of Heterostyly
Abstract The genus Linum consists of over 180 species, the most famous being L. usitatissimum, the source of linen and linseed oil. The eight genera of Linaceae subf. Linoideae, of which Linum isExpand
The phylogenetic history and biogeography of the frankincense and myrrh family (Burseraceae) based on nuclear and chloroplast sequence data.
Molecular phylogenies of an eudicotyledon family previously hypothesized to have a Gondwanan origin, the Burseraceae, are used to test this and other alternative biogeographical hypotheses in light of recalibrated geological events. Expand
Phylogenetic Relationships and Chromosome Number Evolution in Passiflora
The results of phylogenetic analyses of the trnL/trnT sequence data support the reduction of Killip's 22 subgenera to four as proposed in a new classification system by Feuillet and MacDougal (2004), and character optimization of chromosome numbers on the phylogenetic tree supports x=12 as the base chromosome number for Passiflora. Expand
High-resolution phylogeny for Helianthus (Asteraceae) using the 18S-26S ribosomal DNA external transcribed spacer.
This work reveals for the first time a highly resolved gene tree for Helianthus and suggested multiple independent hybrid speciation events that gave rise to at least four polyploids and three diploid hybrids. Expand
Paraphyly of Tarasa (Malvaceae) and Diverse Origins of the Polyploid Species
It is suggested that the unusual morphological features of the tetraploids are the result of convergent evolution and not shared ancestry, and neither the nuclear nor the chloroplast phylogeny supports monophyly of Tarasa as currently circumscribed. Expand
Floral Rewards: Alternatives to Pollen and Nectar
The occurrence of oil production in the Solanaceae (Nierembergia) is reported here for the first time and it is apparent that oil production has evolved independently many times, but plants which produce oils that are collected by female anthophorine bees show similarities in the chemistry of the oils and the types of structures that produce them. Expand