Genomic scanning using AFLP to detect loci under selection in the moss Funaria hygrometrica along a climate gradient in the Sierra Nevada Mountains, Spain

Abstract

The common cord moss Funaria hygrometrica has a worldwide distribution and thrives in a wide variety of environments. Here, we studied the genetic diversity in F. hygrometrica along an abiotic gradient in the Mediterranean high mountain of Sierra Nevada (Spain) using a genome scan method. Eighty-four samples from 17 locations from 24 to 2700 m were fingerprinted based on their amplified fragment length polymorphism (AFLP) banding pattern. Using PCA and Bayesian inference we found that the genetic diversity was structured in three or four clusters, respectively. Using a genome scan method we identified 13 outlier loci, which showed a signature of positive selection. Partial Mantel tests were performed between the Euclidean distance matrices of geographic and climatic variables, versus the pair-wise genetic distance of the AFLP dataset and AFLP-positive outliers dataset. AFLP-positive outlier data were significantly correlated with the gradient of the climatic variables, suggesting adaptive variation among populations of F. hygrometrica along the Sierra Nevada Mountains. We highlight the additional analyses necessary to identify the nature of these loci, and their biological role in the adaptation process.

Maintenance of genetic and morphological identity in two siblingSyrrhopodonspecies (Calymperaceae, Bryopsida) despite extensive introgression

“…These observations contrast with the hypothesis that physiological plasticity prevails over genetic specialization in bryophytes based on experimental work suggesting that, in contrast with the vast majority of angiosperm species, bryophyte species do not tend to develop ecotypes, but rather display an inherent broad ability to cope with environmental variation (Shaw, ). The results presented here contribute to growing evidence for genetic divergence (Szövényi et al, ; Hutsemékers et al, ; Pisa et al, ; Mikulaskova et al, ; Magdy et al, ) and speciation (Johnson et al, ) along environmental gradients in bryophytes, suggesting that adaptation could play a more important role in shaping genetic patterns than previously thought. In particular, an increased role for ecological speciation contrasts with the hypothesis that the failure of bryophytes to radiate is caused by the limited importance of isolation‐by‐environment in the group (Patiño et al, ).…”

Soil Characteristics Influence the Selection of Dominant Plant Genotypes Inhabiting Wadi Sudr, Egypt

“…The 6 loci should reflect the variation continuum among the species and within each species. In Funaria hygrometrica 13 out of 1864 AFLP loci were detected to be under selection using computer software among samples from Sierra Nevada Mountains of Spain, the 13 loci proved to be correlated to the maximum temperatures of each sampled location [16]. However, in the current study the refining was performed and revised manually for each locus.…”

“…The correlation signs (negative or positive) are of no biological relevance, as the genetic variation is not directional and it was generated due to the statistical nature of Mantel test [16] [37].…”

Future directions and priorities for Arctic bryophyte research

“…Elevational gradients are similar to those across latitudes but occur over shorter distances. In an assessment of AFLP signatures in the shuttle life strategist Funaria hygrometrica, genetic structuring along an elevational gradient in the Sierra Nevada Mountains of Spain are suggestive of local adaptation, even in this highly mobile and cosmopolitan species (Magdy et al 2016). One theoretical expectation of local adaptation in species with high migration rates is evolution towards a small number of loci that have a strong effect on local fitness and thus are more likely to undergo strong local selection and remain polymorphic despite the homogenizing effect of migration (Savolainen et al 2013).…”

“…Improvements have been made concerning taxonomy of some Arctic bryophyte species (Hesse et al 2012); however, molecular studies are still needed for most Arctic bryophyte taxa to assess species circumscriptions. DNA barcoding tools (e.g., Hassel et al 2013;Stech et al 2013;Lang et al 2014) would likely standardize identification across the Arctic and combined with other genetic tools promote the study of migration, mating system, and patterns of genetic diversity within consistent taxonomic entities (Zartman et al 2006;McDaniel et al 2013aMcDaniel et al , 2013bMagdy et al 2016). …”