Figure legends
Fig. 1. Design of range expansion evolutionary experiment and
long-term time series of dispersal in the experimental treatments. (A)
Starting from a mix of 20 Paramecium caudatum founder strains,
experimental population were allowed to disperse in 2-patch dispersal
systems. For the range front treatment (red), only the dispersers were
maintained and propagated for 1 week, until the next dispersal episode.
In the core treatment (blue), only the non-dispersing residents were
maintained at each cycle. In the control treatment, both residents and
dispersers were maintained. (B) Observed levels of dispersal over the
whole duration of the experiment (161 cycles, ca. 3 years). Lines show
the trajectories for the individual lines (n = 15), the circles indicate
the mean dispersal per treatment and cycle.
Fig. 2 . Model endpoint predictions for (A) dispersal, (B)
growth rate (r0), and (C) equilibrium density (N ̵̅). In each panel, left:
model predictions for the 3 treatments; right: posteriors distributions
of the most likely winner strains in the range core (AMF_11_11A) and
range front (goe_14) treatment. Circles are the average values measured
for each experimental lines after 15-25 cycles (“short term”).
Different colours represent the different treatments. The black circles
represent the ancestral means (founder population).
Fig. 3. Winning probability (frequency of going to fixation in
10k model runs) of each of 20 strains from the founder population, as a
function of its dispersal, growth rate (r0) and equilibrium density (N
̅), shown for range front (A-C), range core (D-F) and control (G-I)
treatments. Full circles denote the potentially fixed and open circles
the eliminated strains, according to genetic analysis (COI genotype).
Regression lines obtained from multiple regression models. Different
colours represent the different treatments.
Fig. 4. Short- and long-term traits associations observed in
the experiment, in relation to short-term predictions in the model.
(A-C) Bivariate correlations between dispersal, growth rate
(r0) and equilibrium density
(\(\overset{\overline{}}{N}\)). Circles are the average values measured
for each experimental line in year 1 (cycles 15-25; “short term”).
Stars refer to year 2 (cycles 74-84) and cross symbols to year 3 (cycles
154-161). From the distributions of the model predictions (outer part of
graphs), the central range of each trait (50% high density probability
interval, HDPI; thin lines) can be defined; the overlap zones of the
HDPI (shaded square areas) represent the predicted trait association for
each treatment, after short-term evolution. Observations falling outside
of the overlap areas indicate deviation from the model, possibly due to
de novo evolution (year 2 and 3). The black circles represent the mean
ancestral trait association (founder population). (D) Principal
Component Analysis (PCA) of all three traits combined according to the
first two principal components of the PCA. The arrow length represents
the loading value of the trait, while opposite arrow direction indicates
opposite trend between traits. Different symbols correspond to the
different years (circles, year 1; stars, year 2; cross, year 3). The
ellipses are the 95 % containment probability region per treatments and
year. Different colours represent the different treatments.