Figure 2 Caption:
Comparison of model
parameters for onset (panels A, B, C) and termination (panels D, E, F)
dates as a function of latitude. Panels A and D show latitude
coefficients for 22 species onset and termination phenology. Values
extracted from Fric et al. (2020) Supplemental Table 2 using regression
of residuals against latitude, corrected for year and altitude, are
shown as squares. Circles are parameters from the reanalysis. Filled
symbols indicate significant slopes with latitude. Panels B and E show
values and boxplots of the model coefficients for DOY ~
latitude, colored by response: positive (green), non-significant (gray),
or negative (blue) correlations. Panels C and F are stacked barplots of
the response signs representing the number of datasets demonstrating
positive (green), non-significant (gray), or negative (blue)
correlations with latitude. Panels B, C, E, and F show four sets of
model results extracted from Fric et al. Supplemental Table 2, and one
set of reanalysis results. For Fric et al. (2020) results, “SR”
represents single regressions for DOY ~ latitude, while
“RR” represents regression of residuals against latitude, corrected
for altitude and year. “SR-105” and “RR-105” show results for all
105 datasets in the original analysis, while “SR-22” and “RR-22”
only include results for the 22 species-region datasets used in our
reanalysis. “New” shows results from our curation and reanalysis of
those 22 species-region datasets. See Supplemental Figure 1 for a
comparison of species-specific data and results.
Supplemental
Figure 1 Caption:
These panels display
the data and regression results for onset and termination across models.
Each row of 3 panels represents a species in the re-analysis. In the
left column, all raw occurrence data are shown as “+” while onset and
termination are shown as ⧫; red points indicate individual observations
used as both onset and termination. Fric et al.’s single regression
results of DOY ~ latitude for onset and termination are
overlaid on the data. In the middle column, the residuals used in the
Fric et al. (2020) regression of residuals are shown for onset (▲) and
termination (▼), respectively, with red indicating records of
observations used as both onset and termination. Because each dataset
comprises residuals, the “phenology shift” data are centered around 0
and the termination axis is shifted for easier interpretation. The
slopes display the regression of residuals results from Fric et al.
(2020) as reported in their supplementary tables. The right column shows
the calculated onset (▲) and termination (▼) phenometrics calculated
using the phest package in R. (Multiple observations for a latitudinal
band represent different years), with the results from the multiple
regression reanalysis. For all panels, the line format demonstrates
positive (green, dashed), non-significant (black, dotted), or negative
(blue, dashed) correlations with latitude in the corresponding models.
While the Fric et al. analyses were generally reproducible, significance
coding matches that reported in Fric et al. Supplemental Table 2, rather
than our reproduction. We were unable to reproduce p values <
0.05 for the following single regression analyses: E. maturnaonset and L. virgaureae termination.