DATA of mating pairs from 32 samples in L. saxatilis

The data provide size distribution of male (size1) and female (size2) in Littorina saxatilis mating pairs from 32 samples (pop). The samples are classified in two groups (area), those representing bimodal populations with tw ecotypes living in sympatry and able to meet for mating (area 1) and those living in unimodal populations with only one ecotype present. For every mating pair the ecotype type of each sex, mor1 (for male) and mor2 (for female) is also provided (1 shelter, 2 intermediate and 3 exposed ecotypes)

Historical Biogeography of the Marine Snail <i>Littorina saxatilis</i> Inferred from Haplotype and Shell Morphology Evolution in NW Spain

<div><p>The marine snail <i>Littorina saxatilis</i> exhibits extreme morphological variation between and within geographical regions and represents an excellent model for assessing local adaptation. Previous studies support the hypothesis of parallel evolution in sympatry of two morphologically different ecotypes (named as RB and SU) that co-inhabit different habitats from Galician rocky shores (NW Spain), and which are interrupted by sheltered areas inhabited by a different morph never studied before (named as SRB). Here, we use morphological and mitochondrial DNA (mtDNA) sequence data to test hypotheses on the origin and diversification of SRB snails and to assess their evolutionary relationships with RB and SU ecotypes. Our results show that the SRB morph displays the largest size and shell elongation and the smallest relative shell aperture, representing an extreme type of the RB vs. SU polymorphism, which has been linked to adaptation to sheltered ecological factors. Phylogenetic analysis shows that the SRB morph shares ancestry with RB and SU ecotypes, rejecting the hypothesis that the SRB morph marks relict populations from which these ecotypes evolved in Galician coasts. Our data support that genetic differentiation among SRB, RB and SU morphs results from a general pattern of restricted gene flow and isolation by distance linked to the colonization of Galician coasts by two independent mtDNA lineages, rather than from a random fragmentation of the initial distributional range. Therefore, the confinement of distinct lineages to specific geographical areas denote evident limits to the distances these snails can disperse. Morphological analysis indicates no association between mtDNA lineage and a specific morphotype, and suggests the independent gain of convergent morphological patterns within each mtDNA lineage in populations occupying contrasting habitats following the colonization of Galician coasts.</p></div

Phylogenetic relationships among Galician snails.

<p>(a) Phylogram of Galician <i>L</i>. <i>saxatilis</i>. Numbers above branches indicate bootstrap node support in RAxML/Bayesian posterior probability in MrBAYES. Only bootstrap values and posterior probabilities of, respectively, 60% and 0.7 or greater are depicted. (b) Location of sampling sites. (c) Statistical parsimony network. Pie charts represent the frequencies at each locality. Each white circle represents a mutational step. Note that clade I specimens from Tapia are clustered together with Arealonga clade I specimens in the same pie chart. In all panels, colour and symbol designation indicates geographic origin.</p

Mean (±SD) of the significant variables derived from the geometric morphometrics analyses.

<p>Results are given for each morphotype and locality, including the results from both the randomization (ignoring the origin of the localities) and the nested (including the geographical origin) ANOVAS, indicating the existence of significant differences among morphotypes.</p

2-DE spot volumes_Proteomic data Littorina

Normalised and log10-transformed data obtained from two-dimensional electrophoresis (2-DE) image analyses by using SameSpots v3.3 software (Nonlinear Dynamics Ltd). 2-DE gels were silver stained

Geometric morphometrics analysis.

<p>a) Individuals from different ecotypes (SRB, RB and SU) and localities plotted for size (CS) and the relative shell aperture (RW1) of shell shape. b) Photo and corresponding thin-plate spline representation of the geometric deformations explained by RW1 for the three ecotypes (SRB, RB and SU). Percentages correspond to aperture size values.</p

LittorinaSaxatilis_AFLPs

LittorinaSaxatilis_AFLP

ThioPer-2_Final-NoIndel_Intron

ThioPer-2_Final-NoIndel_Intro

Lsaxatilis_AFLPs-1

AFLP data file. See 'readme' for additional descriptio

Cal-1_Final-NoIndel_Intron

Cal-1_Final-NoIndel_Intro