0000000000388748
AUTHOR
Pieter B. Pelser
Patterns and causes of incongruence between plastid and nuclear Senecioneae (Asteraceae) phylogenies
One of the longstanding questions in phylogenetic systematics is how to address incongruence among phylogenies obtained from multiple markers and how to determine the causes. This study presents a detailed analysis of incongruent patterns between plastid and ITS/ETS phylogenies of Tribe Senecioneae (Asteraceae). This approach revealed widespread and strongly supported incongruence, which complicates conclusions about evolutionary relationships at all taxonomic levels. The patterns of incongruence that were resolved suggest that incomplete lineage sorting (ILS) and/or ancient hybridization are the most likely explanations. These phenomena are, however, extremely difficult to distinguish beca…
An ITS phylogeny of tribe Senecioneae (Asteraceae) and a new delimitation of Senecio L.
Senecioneae is the largest tribe ofAsteraceae, comprised ofca. 150 genera and 3,000 species. Approximately one-third of its species are placed in Senecio, making it one of the largest genera of flowering plants. Despite considerable efforts to classify and understand the striking morphological diversity in Senecioneae, little is known about its intergeneric relationships. This lack ofphylogenetic understanding is predominantly caused by conflicting clues from morphological characters, the large size ofthe tribe, and the absence of a good delimitation of Senecio. Phylogenetic analyses of nrITS and plastid DNA sequence data were used to produce a hypothesis of evolutionary relationships in Se…
The genetic ghost of an invasion past: colonization and extinction revealed by historical hybridization inSenecio
Hybridization is an important evolutionary factor in the diversification of many plant and animal species. Of particular interest is that historical hybridization resulting in the origin of new species or introgressants has occurred between species now geographically separated by great distances. Here, we report that Senecio massaicus, a tetraploid species native to Morocco and the Canary Islands, contains genetic material of two distinct, geographically separated lineages: a Mediterranean lineage and a mainly southern African lineage. A time-calibrated internal transcribed spacer phylogeny indicates that the hybridization event took place up to 6.18 Ma. Because the southern African lineage…
The Global Naturalized Alien Flora (GloNAF) database.
This dataset provides the Global Naturalized Alien Flora (GloNAF) database, ver-sion 1.2. Glo NAF represents a data compendium on th e occurrence and identit y of naturalizedalien vascular plant taxa across geographic regions (e.g. countries, states, provinces, districts,islands) around the globe. The dataset includes 13,939 taxa and covers 1,029 regions (including381 islands). The dataset is based on 210 data sources. For each ta x on-b y-region combination, wepr ovide information on whether the tax on is consider ed to be naturalized in the specific region(i.e. has established self-sustaining popula tions in the wild). Non-native taxa are marked as“alien”, when it is not clear whether the…