Repeated evolution of net venation and fleshy fruits among monocots in shaded habitats confirms a priori predictions: evidence from an ndhF phylogeny.

We present a well-resolved, highly inclusive phylogeny for monocots, based on ndhF sequence variation, and use it to test a priori hypotheses that net venation and vertebrate-dispersed fleshy fruits should undergo concerted convergence, representing independent but often concurrent adaptations to shaded conditions. Our data demonstrate that net venation arose at least 26 times and was lost eight times over the past 90 million years; fleshy fruits arose at least 21 times and disappeared 11 times. Both traits show a highly significant pattern of concerted convergence (p<10(-9)), arising 16 times and disappearing four times in tandem.

An expanded plastid DNA phylogeny of Orchidaceae and analysis of jackknife branch support strategy.

An expanded plastid DNA phylogeny for Orchidaceae was generated from sequences of rbcL and matK for representatives of all five subfamilies. The data were analyzed using equally weighted parsimony, and branch support was assessed with jackknifing. The analysis supports recognition of five subfamilies with the following relationships: (Apostasioideae (Vanilloideae (Cypripedioideae (Orchidoideae (Epidendroideae))))).

The phylogeny of Gaura (Onagraceae) based on ITS, ETS, and trnL-F sequence data.

Gaura (Onagraceae: Onagreae) is a small North American genus of 21 species consisting mostly of night-blooming, moth-pollinated annuals and perennials. The current infrageneric classification based on differences in habit, floral symmetry, and fruit morphology recognizes eight sections within the genus. We examine the phylogenetic relationships of all 21 species of Gaura using DNA sequence data from the internal transcribed spacer region (ITS), the external transcribed spacer region (ETS), and the plastid trnL-F region.

Molecular systematics and biogeography of the amphibious genus Littorella (Plantaginaceae).

Littorella (Plantaginaceae) is a disjunct, amphibious genus represented by three closely related species. Littorella uniflora occurs in Europe including Iceland and the Azores, L. americana is found in temperate North America, and L.