Supplemental material for
Long-term culture at elevated atmospheric CO2 fails to evoke specific adaptation in
seven freshwater phytoplankton species
Content:
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Supplemental Figure 1: Aqueous CO2 concentration
Supplemental Figure 2: Growth curves for final reciprocal transplant
Supplemental Figure 3: pH in final growth cycle
Supplemental Figure 4: pH in final growth cycle
Growth curves and parameter plots for all reciprocal transplants and using a exponential
fitting, logistic least squares fitting and maximum likelihood fitting are available and can
be rendered from the data using the accompanying R scripts. Results from all reciprocal
transplants, parameters and fitting methods are consistent with the results presented in the
manuscript.
Anabaena
Chlamy−
domonas
Navicula
Nitzschia
Pseudo−
kirchneriella
Scenedesmus Synechococcus
100
Regime 1
80
60
40
20
1000
800
Regime 2
Aqueous CO2 (ppm)
120
600
400
200
0
ambient high
ambient high
ambient high
ambient high
ambient high
ambient high
ambient high
CO2 environment
Supplemental figure 1: Aqueous CO2 concentration at the end of the final transfer cycle.
Results for regime 1 are presented in the top panel (1) and for regime 2 in the lower panel
(2), no aqueous phase to measure in regime 3. There is an overall difference in CO2
between treatment in both regimes and ambient CO2 lines are exposed to lower CO2
minima.
Anabaena
Chlamy−
domonas
Navicula
Nitzschia
Pseudo−
kirchneriella
Scenedesmus
Synechococcus
2.0
Regime 1
1.5
1.0
0.0
0.6
Regime 2
Absorbance
0.5
0.4
0.2
Regime 3
0.6
0.5
0.4
0.3
0.2
0.1
0 2 4 6 8
0 2 4 6 8
0 2 4 6 8
0 2 4 6 8
0 2 4 6 8
0 2 4 6 8
0 2 4 6 8
Time (days)
Supplemental figure 2: Growth curves for final reciprocal transplant. From top to
bottom, panels present values for regime 1 (high nutrient liquid culture), for regime 2
(lower nutrient liquid culture) and for regime 3 (solid agar culture). Vertical lines denote
the duration of a transfer cycle in each regime. Points are measured values; lines are fitted
values, values presented individually for each selection line. Red indicates growth at high
CO2, blue indicates growth at ambient CO2; the separating of red and blue points
represents the fertilization effect of CO2. Solid lines indicate ambient selection history,
dashed lines indicate elevated CO2 selection history; the lack of consistent separation
between solid and dashed lines of the same color reflects the lack of an evolutionary
response.
Supplemental figure 3: pH of media after 5 days of growth in final transfer. Results for
regime 1 are presented in the top panel (1) and for regime 2 in the lower panel (2), no
aqueous phase to measure in regime 3. There is an overall difference in pH between
treatment only in regime 2 and in this regime; pH changes will compound the effect of
elevated CO2, by increase the amount of carbon available as CO2 in the media.
Supplemental figure 4: CO2 concentration in the air between the media surface and the
stopper after 5 days of growth in final transfer. Results for regime 1 are presented in the
top panel (1) and for regime 2 in the lower panel (2), the air space is too small to measure
in the regime 3. In regime 1, the phytoplankton can draw CO2 concentration down to
equivalent levels in both treatments. In regime 2, the phytoplankton can lower the CO2
concentration, but the difference between treatments remains.