Regional Environmental Breadth Predicts Geographic Range and Longevity in Fossil Marine Genera
Figure 2
Mean genus duration and geographic range for 39 Linnaean classes in North America.
The red crosses are ± two standard errors around the mean for all genera in each category. The red boxes outline the expected values for all endemic and cosmopolitan genera if durations and geographic ranges were randomly distributed among taxa. The boxes show the middle 95% of values from 10,000 bootstrapping iterations. Note the significant disjunct between observed and expected mean genus durations and geographic ranges. (A) Endemic vs. cosmopolitan duration within North America. (B) Endemic vs. cosmopolitan geographic range, calculated as a convex hull around PaleoDB collections, within North America. (C) Endemic vs. cosmopolitan geographic range, calculated as proportion of the total available rock area occupied by a genus within North America. Only one value for each genus (the mean geographic range) is used in the per class calculations. Error bars are ± one standard error of class mean. The one-to-one line (dashed) is plotted for reference. A key to class identity along with observed and expected values for the aggregation of all genera are given in Figure S2.