Is a population of rare cress found near Bristol, UK, a remnant of an ice age population, or is it part of a wider European population that survived in refugia somewhere?Continue reading ‘Out of Iberia’: How Bristol rock cress got to where it is today
Tagged: evolutionary history
Analysis of over 3300 single copy genes has produced a well-supported topology with some significant changes.Continue reading Single copy genes produce a clearer phylogeny of the Apioideae
The Qinghai-Tibetan Plateau (QTP) is extremely rich in species, but why? One recent explanation is the mountain‐geobiodiversity hypothesis (MGH) by Mosbrugger et al. The argument is that biodoversity happens when you have a large range of elevations, in close proximity, with climatic change that acts as a ‘species-pump’. In a recent paper, Peng-Cheng Fu and colleagues investigated the evolutionary history of three closely related Gentiana endemic species, to see if it was compatible with this hypothesis. Gentiana is found around the world in montane habitats. It’s often prized by gardeners for its deep trumpet flowers with petals of striking blue....Continue reading What creates Gentiana diversity in mountains?
In southeast China there is a puzzle. Pseudotaxus chienii lives as a relict, a plant that used to have a much wider geographic range. Now it’s limited to comparatively few locations. This is common for many plants that have found past climate change a challenge. The puzzle is that these relict populations appear to be the same species. If these plants have been isolated, why hasn’t distance, and evolution, driven a wedge between them? Yixuan Kou and colleagues have been examining the evolutionary history of P. chienii to find out. The team examined fourteen nuclear loci as well as two...Continue reading Evolutionary history of Pseudotaxus: old lineage, young populations
Phylogenetic and demographic analyses were employed to shed light on the species boundaries, evolutionary history and species diversity of genus Aubrieta (Brassicaceae). DNA sequence based mismatch-distribution and climate-niche analyses were performed to explain various radiations in space and time during the last 2.5 million years since the Pleistocene in the Eastern Mediterranean and Asia Minor. Koch et al. demonstrate that Anatolia served as the primary centre for subsequent diversification in Greece and expansion South to Lebanon and West to the Balkans and Italy. Early expansion and diversification showed adaptation trends towards higher temperature and drier conditions with subsequent secondary diversification...Continue reading Evolution of Rainbow rockcress highlights Anatolia as a cradle of biodiversity
Hordeum marinum (sea barley) is a complex species that is usually recognized as having two subspecies, marinum (2n = 2x = 14) and gussoneanum (2n = 2x =14 and 2n = 2x = 28). Carmona et al. use comparative physical mapping of repetitive DNA to determine the genome structure of several H. marinum accessions representing all taxa and cytotypes. They detect two subgenomes in the tetraploids, which appear to have come about through a cross between a diploid gussoneanum progenitor and a second, related – but unidentified – diploid ancestor. They conclude that the allopolyploids are segmental in nature with two...Continue reading Evolutionary history of sea barleys (Hordeum marinum)