Figures legends:
Figure 1: Locations of study sites of collection ofAmnicola limosus populations in the St. Lawrence River system and
experimental design of reciprocal transplant experiment. A: The study
sites are located near the island of Montreal, QC, Canada (right of the
map). Sites are colored based on water calcium concentration (mg/L).
Sites with gobies absent are HA-LCGA, OKA-LCGA, IB-LCGA, PB-LCGA,
IPE-LCGA, and sites with gobies present are PG-HCGP, PST-HCGP, PON-HCGP,
BEA-HCGP, GOY -HCGP. The two exceptions are RAF-LCGP (low calcium and
gobies present) and PDC-HCGA (wetland, high calcium, and gobies absent).
B: Experimental design showing the two origin waters (Ottawa River in
grey or St. Lawrence River in blue) with six populations from each river
(replicates), water treatment (OR-LC: Low calcium - Ottawa River; SL-HC:
St. Lawrence River - high calcium) and goby cue treatment (\(+\)/\(-\):
with or without).
Figure 2: Results of the environmental association
analyses. (A) Biplot of the q-values obtained from the poolFreqDiff
analysis testing for consistent differences in allele frequencies
between populations from invaded and uninvaded environments, as a
function of the q-values derived from the C2-statistic
in the STD model in Baypass, assessing the association of SNP allele
frequencies with goby presence/absence. The dashed vertical and
horizontal grey lines indicate the FDR of α 0.01. ( B) Biplot of
the q-values for the poolFreqDiff analysis comparing populations of low
and high calcium habitats as a function of the Bayes Factor (BFis) from
the Baypass STD model (median of three independent runs) testing the
association with calcium concentration. The dashed vertical line (BFis
> 20 dB) indicates outlier SNPs significantly associated
with the calcium covariable and the horizontal line gives the q-value
FDR of α 0.01.
Figure 3: Fecundity (total number of eggs produced) and survival
as a function of water treatment, origin water, and goby cue treatment
in the reciprocal transplant experiment. Each dot represents a
measurement for one population (blue: St. Lawrence populations HCGP,
grey: Ottawa river populations LCGA), summarized by the corresponding
boxplots (showing the median, minimum and maximum, values,
1st and 3rd quartiles, and outliers
as full dots). The black dots are the mean for each treatment, with
squares and triangles for treatments with or without goby cues.
Fecundity was analyzed with a GLM (negative binomial distribution), with
only the origin water being significant (p = 0.015). Survival was
analyzed with a GLMM (binomial distribution), with the origin and
treatment water being significant (p = 0.020 and p = ,
respectively).
Figure 4: Genome-wide diversity indices. (A) violin plots of
nucleotide diversity pi, (B) Watterson’s Theta, (C) and Tajima’s D
according to habitats (Ottawa River LCGA; St. Lawrence River HCGP), with
median and interquartile ranges shown in the box plot insert. (D)
Observed heterozygosity per population, comparing habitat types (black
dots: average per habitat, error bars show one standard error interval),
except for PDC (HCGA, wetland refuge) and RAF (LCGP) which have inverted
calcium concentration and goby presence characteristics.
Figure 5: Population genetic structure. (A) Heatmap of the
scaled covariance matrix Ω (with ρij the correlation
coefficient between pairs of populations) with hierarchical clustering
tree (using the average agglomeration method), obtained from the core
model of Baypass. (B) Pairwise FST matrix between the
twelve study populations. The gray bars correspond to the Ottawa River
populations (LCGA) and the blue bars to the St. Lawrence populations
(HCGP), except for PDC (HCGA, wetland refuge) and RAF (LCGP).