10.5061/DRYAD.9ZW3R22F0
Neto-Bradley, Barbara
0000-0002-6061-208X
University of British Columbia
Muir, Christopher
University of Hawaiʻi
Whitton, Jeannette
0000-0003-1609-5203
University of British Columbia
Pennell, Matthew
University of British Columbia
Data from: Phylogenetic history of vascular plant metabolism revealed
using a macroevolutionary common garden
Dryad
dataset
2021
2021-05-13T00:00:00Z
2021-05-13T00:00:00Z
en
93851015 bytes
1
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
While the fundamental biophysics of C3 photosynthesis is highly conserved
across plants, substantial variation in leaf structure and enzymatic
activity translates into variability in rates of photosynthesis. Although
this variation is well-documented, it remains poorly understood how
photosynthetic rates evolve over short and long time scales, and whether
these macroevolutionary changes are related to the evolution of key
morphological and biochemical leaf traits. Large-scale comparative studies
have been hampered by the substantial logistical and statistical
challenges in disentangling evolutionary adaptation from environmental
acclimation. Here we get around this limitation with a ‘macroevolutionary
common garden’ approach in which we measured the metabolic traits Jmax and
Vcmax from 111 phylogenetically diverse species in a shared environment.
Using several phylogenetic comparative methods, we find substantial
phylogenetic signal in these traits at shallow phylogenetic scales, but
this signal dissipates quickly at deeper time scales. Leaf morphological
traits exhibit phylogenetic signal over much deeper time scales,
suggesting that these traits are less evolutionarily constrained than
metabolic traits. Furthermore, we find that while morphological and
biochemical traits (LMA, Narea and Carea) are weakly predictive of Jmax
and Vcmax, evolutionary changes in these traits are mostly decoupled from
changes in metabolic traits. This lack of tight evolutionary coupling
implies that it may not be possible to use changes in these functional
traits in response to global change to infer that photosynthetic strategy
is also evolving.
There are 3 sets of data files, corresponding to measurements taken for
138 individuals growing at the UBC and Van Dusen Botanical Gardens in
Vancouver, BC, Canada. All of these data have been measured on the same
set of leaves, between May and September of 2019. n.b. Following data
processing and quality checks, only data for 111 species were used in the
final analysis. 1. Rapid A/Ci Response (RACiR) data Find these data in
neto-bradley_et_al_2021_physiological_data.zip Files are named in the
following format yyyy-mm-dd-hhmm_genus_species Provided in .txt format, as
output by the LiCor6800 machine. Blurb: RACiR curves (as described in
Stinziano et al. 2017) characterize the change in Net photosynthesis A
relative to changes in CO2. Functionally this describes the physiological
constraints of how quickly and efficiently a plant can take up CO2. During
our RACiR curve measurements, CO2 is ramped from 10 ppm to 1010 ppm at a
rate of + 100 ppm per minute. While this is ongoing, CO2 accumulates in
the chamber such that the true CO2 contents of the chamber are slightly
out of sync with the concentration of CO2 measured by the machine. In
order to correct for this lag, two curves are measured - a data curve and
an empty curve for callibrating the data curve. Data Specifics: The
RACiR data is comprised of 2 data files: an "empty curve" and a
"data curve" (see above.) The empty curve characterizes how CO2
accumulates in an empty chamber throughout the course of the A/Ci
measurement, and the data curve characterizes a leaf's photosynthetic
rates change in response to increasing CO2. Empty curves were collected
every hour to two hours - for every empty curve multiple that were
collected in close temporal proximity can be corrected (for the lag in CO2
measured - as described above.) Every measurement has its own txt file
that was generated by the LiCor6800 machine when the measurement was
finalized. Time & Place: RACiR curves were measured on the
youngest fully expanded leaves of each of the 138 species studied here.
These measurements were taken between May 5th and July 18th 2019 at the
UBC and VanDusen Botanical Garden. 2. Morphological data Find these data
in neto-bradley_et_al_2021_morphological_data.csv Blurb: After each
RACiR curve was measured, the leaf (or several leaves in the case of small
leaves/needles) on which this was taken were harvested and put in a sealed
bag, which was stored in a cooler overnight. The next morning, the leaves
were measured for fresh mass and leaf area. The leaves were then dried for
48 hours in an oven at 60 degrees Celsius. After this the leaves were
weighed for dry mass. Time & Place: These measurements were
taken the day of, or the following day at the Beaty Biodiversity Research
Centre at the UBC Vancouver Campus. 3. Biochemical data Find these data
in neto-bradley_et_al_2021_biochemical_data.csv Blurb: Once the leaf
tissues were dried, these were sent off for chemical analysis for the
Nitrogen and Carbon contents by combustion. Time & Place: These
measurements were done at the Analytical Chemical Services Laboratory (at
the BC Ministry of Environment and Climate Change Strategy), during
September 2019.