How do temperate bryophytes face the challenge of a changing environment? Lessons from the past and predictions for the future

Abstract

Bryophytes are a group of early land plants, whose specific ecophysiological and biological features, including poikilohydry, sensitivity to moderately high temperature and high dispersal ability, make them ideal candidates for investigating the impact of climate changes. Employing a combined approach of species distribution modelling (SDM) and molecular phylogeography in the temperate moss Homalothecium sericeum, we explore the significance of the Mediterranean refugia, contrasting the southern and northern refugia hypotheses, determine the extent to which recolonization of previously glaciated areas has been facilitated by the high dispersal ability of the species and make predictions on the extent to which it will be impacted by ongoing climate change. The Mediterranean areas exhibit the highest nucleotidic diversities and host a mixture of ancestral, endemic and more recently derived haplotypes. Extra-Mediterranean areas exhibit low genetic diversities and Euro-Siberian populations display a significant signal of expansion that is identified to be of Euro-Siberian origin, pointing to the northern refugia hypothesis. The SDMs predict a global net increase in range size owing to ongoing climate change, but substantial range reductions in southern areas. Presence of a significant phylogeographical signal at different spatial scales suggests, however, that dispersal limitations might constitute, as opposed to the traditional view of spore-producing plants as efficient dispersers, a constraint for migration. This casts doubts about the ability of the species to face the massive extinctions predicted in the southern areas, threatening their status of reservoir of genetic diversity.

Modeling Species Distributions from Heterogeneous Data for the Biogeographic Regionalization of the European Bryophyte Flora

“…The presence of such hyper-oceanic species as Saccogyna viticulosa and Dicranum scottianum in western Scandinavia and western Iberian Peninsula should hence be considered as an irradiation of an Atlantic element into regions that otherwise belong to the core Alpine and Mediterranean regions, respectively. This spatial congruence found between biogeographic regions defined for vascular plants and bryophytes reinforces the notion that, despite the substantial differences in ecophysiology and dispersal ability between the two groups, post-glacial migration patterns might have been much more similar between them than previously thought [68].…”

Conservation of Portuguese red-listed bryophytes species in Portugal: Promoting a shift in perspective on climate changes

“…Employing a combined approach of SDMs and molecular phytogeography, the significance of the Mediterranean refugia, contrasting the southern and northern refugia hypotheses, has been highlighted for some mosses such as the temperate species Homalothecium sericeum (Désamoré et al 2012). …”

Glacial refugia and post-glacial colonization patterns in European bryophytes

“…long before the LGM). Désamoré et al (2012) found northern refugia the most likely origin of the northern European colonization. Haplotype groups restricted to southwestern genetic clusters are also found in Kindbergia praelonga (Hedw.)…”