Figure 4a-d. Metrics of biogeographical overlap and endemism,
used for across-family analyses on the mechanisms shaping the slope of
ERR.
Each point represents a species-rich plant family (n=60), with size of
point representative of family richness. Three families labeled as
examples for comparisons between scatterplots: 1) Dipterocarpaceae, 2)
Ericaceae, 3) Pteridaceae. On the y-axis, slope of average elevation
range-size (m), abbreviated as ERR, as a function of position along an
elevational gradient (m a.s.l.). On the x-axis, familial metrics of
distribution by Malesian biogeographical region (Sundaland, Wallacea, or
Sahul), with values ranging from 0 - 1. Plots 4a-c representendemism , defined as the proportion of species that exclusively
occur within a single biogeographical region. Plot 4d representscosmopolitanism , defined as the proportion of species that occur
in all three biogeographical regions. Not shown is the overlapmetric, defined as the proportion of species occurring within a given
biogeographical region and with the potential to occur elsewhere,
summarized in Table 1. Linear regression results shown as a black slope,
phylogenetic independent contrasts as a red slope, both plotted without
scaling; dashed lined represent non-significance. Point colors (CMYK
model) represent the combined metrics of biogeographic association of
each family, with endemism to Sundaland represented as magenta tones,
Wallacea as yellow, Sahul as cyan, and cosmopolitan as black, with 25%
transparency. Full color legend for the 60 families in Supporting
information.