APPENDIX S1. Specimen collection frequency across day of flowering
year (DOFY), a normalized version of the Julian day of year.
Red vertical dashed lines correspond to January 1.
APPENDIX S2. Comparison of species peak flowering season
(in Julian days) recorded from herbarium specimen records
versus the literature (Rebelo, 2001). Rebelo (2001) reports both
a “long” season of increased flowering activity and a narrower
“short” season of maximal flowering activity for each species, the
centers of which are shown here relative to the peak flowering
date we calculated from herbarium data as described in the text.
Although the y-axis
ranges from 0–365, the x-axis
has a slightly
broader range—given the circular nature of the calendar year, a
given Julian date can take multiple values (e.g., 10 = 375), and the
value that best communicates alignment with the field guide data
set is shown.
APPENDIX S3. Parameters used to characterize phenologic responsiveness
to climate in Protea species, estimated from the mixed
effects model.
APPENDIX S4. Changes in flowering times of Protea species across
South Africa in relation to anomalies in temperature. Statistical
analysis based on mixed effects model using both spatial temperature
variation (A) and temporal climate (year-to-
year
temperature
variation) (B) as predictors, with species as random effect. Negative
slopes indicate advancement of flowering with warming. Lines indicate
fitted slopes for individual Protea species. Points indicate input
specimen data, and have been truncated for visualization at the extremes
of the y-axis
range.
APPENDIX S5. Species-specific
statistics generated by the sliding
window phenology analysis and the mixed effects model (MEM)
climate analysis for each of the 25 Protea species.
APPENDIX S6. Relationship between the aseasonality of species’
annual flowering phenology cycles (aseasonality index) and their
estimated phenological responses to temperature variation across
space and time (coefficients from the linear mixed effects model).
Dashed lines show linear regressions with 95% confidence intervals
shaded.
APPENDIX S7. Tests of phylogenetic signal in different dimensions
of Protea flowering.