Table 1.
Summary of the empirical support for the three evolutionary models
| Model | Median model support | Frequency with which each model is best supported |
||||||
|---|---|---|---|---|---|---|---|---|
| All | By trait type |
By fossil group |
||||||
| Size | Shape | Other | Plank micro | Benth micro | Macro | |||
| Directional change | 0.06 (0.04, 0.08) | 13 | 5 | 4 | 4 | 5 | 3 | 5 |
| Random walk | 0.47 (0.39, 0.56) | 123 | 67 | 43 | 13 | 24 | 57 | 42 |
| Stasis | 0.34 (0.20, 0.50) | 115 | 42 | 68 | 5 | 12 | 37 | 66 |
The first column indicates the median model support, measured as Akaike weight, with 95% confidence intervals generated by bootstrap resampling the observed weights 10,000 times. The remaining columns give the frequencies for which each of the indicated models is the best supported of the three, first tabulated over all sequences, then split across trait types and taxonomic categories. ″Other″ traits are mostly meristic (count) variables, with a few multivariate descriptors that include aspects of both size and shape. The fossil groups are listed in order of planktonic microfossils (Plank micro), benthic microfossils (Benth micro), and macrofossils (Macro).