SUPPLEMENTARY INFORMATION

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Gordon Stafford
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ULEMENTARY INFRMATIN ART 1: ULEMENTARY FIGURE Relative substrate affinity!0.04!0.02 0.00 0.02 0.04 0.

Relative substrate affinities for epkoskiʼs alaeozic and Modern EFs.

1 ULEMENTARY INFRMATIN ART 1: ULEMENTARY FIGURE Relative substrate affinity!0.04! !0.04! A B m aleozoic Evolutionary Fauna Modern Evolutionary Fauna carbonate silciclastic g silciclastic carbonate m Figure 1. Relative substrate affinities for epkoskiʼs alaeozic and Modern EFs. Relative substrate affinities can be determined by first calculating the expected number of occurrences for the ith EF and jth lithology in each time interval as E ij = i j ij i j i j where Eij is the expected number of occurrences in the ith EF and jth lithology and ij is the total number of all occurrences in the time interval. Relative affinity is the difference between the number of observed and expected occurrences scaled to the total number of occurrences. Relative affinities, by definition, require that an excursion from zero be offset by an excursion from zero in the opposite direction when summed over all other EFs and lithologies, just as relative proportions require that an increase in the relative abundance of one taxon must cause a decrease in the relative abundance of all other taxa combined. In this figure, the offsets are not perfectly antithetical because the ambrian EF and collections with unspecified lithologies were included in the calculation but, for clarity, not plotted. Affinities for individual time intervals are sensitive to coverage and sampling in the aleobiology atabase and are, therefore, best considered in aggregate, as reported in the main text. g 1

2 ULEMENTARY INFRMATIN A B pearman rank-order correlation -value g g !0.5! Figure 2. pearman rank-order correlation coefficients and -values between EF genus extinction rates and siliciclastic truncation rates (first differences). A) orrelation coefficients for Modern EF extinction and siliciclastic truncation. B) -values ( 0.05) for coefficients in A. ) orrelation coefficients for alaeozoic EF extinction and siliciclastic truncation. ) -values ( 0.05) for coefficients in. Figure shows correlations for all possible combinations of time series starting and ending points. osition on abscissa gives the starting time interval, position on ordinate indicates the number of time intervals after the starting interval that are included (minimum is three). Thus, the upper diagonal shows the correlation for time series staring at the corresponding x-axis interval and ending in the youngest time interval (liocene, diagonal is irregular due to variations in interval duration). Values given in Table 1 correspond to the upper left-hand cells (emadocian-liocene). Values below dashed line are alaeozoic-only comparisons. Modern EF extinction rates are positively correlated with siliciclastic truncation rates for a wide range of time series positions. After the ilurian, during which time the Modern EF has a negative correlation with siliciclastics, the Modern EF is significantly positively correlated with siliciclastics in the alaeozoic. The alaeozoic EF, by contrast, is positively correlated with siliciclastics over a narrower range of intervals and in only two alaeozoic time series positions. Note that the alaeozoic EF is significantly positively correlated with siliciclastics through some of the post-alaeozoic, but that the correlations are generally weaker than the correlations for the Modern EF. pearman rank-order correlation -value g g !0.5!

3 ULEMENTARY INFRMATIN A pearman rank-order correlation !0.5! pearman rank-order correlation !0.5!1.0 g g B value value g Figure 3. As in Figure 2, but for carbonates. ue to the limited number of carbonate packages in the post-alaeozoic, only rdovician-ermian data are shown. A) orrelation coefficients for Modern EF extinction and carbonate truncation. B) -values ( 0.05) for coefficients in A. ) orrelation coefficients for alaeozoic EF extinction and carbonate truncation. ) -values ( 0.05) for coefficients in. The upper diagonal shows the correlation for time series staring at the corresponding x-axis interval and ending in the youngest time interval (Tatarian, diagonal is irregular due to variations in interval duration). Note that the alaeozoic EF is significantly positively correlated with carbonates for many of the possible combinations of starting and ending intervals, whereas the Modern EF is not. Note also the consistently poor or negative correlations in the ilurian. This interval of poor or negative correlation reduces the correlations reported in Table 1. After the ilurian, alaeozoic EF extinction rates and carbonate truncation rates have significant coefficients as high as Why the ilurian-early evonian has consistently low or negative correlations between environment and EF is currently unknown, but the temporally localized nature of the divergence suggests higher than average chronostratigraphic errors during this time interval or sedimentation patterns in North America that diverge markedly from the global average. g 3

4 ULEMENTARY INFRMATIN Mean siliciclastic correlation!1.0! alaeozoic only 1:1!1.0! Mean carbonate correlation Figure 4: Mean pearman rank-order correlation coefficients for all significant correlations from Figures 2 and 3. Time series are limited to the alaeozoic so that both carbonates and siliciclastics can be compared on identical terms. n average in the alaeozoic, the alaeozoic EF is positively correlated with carbonates and negatively correlated with siliciclastics. The Modern EF, on the other hand, is positively correlated with both siliciclastics (r = 0.632) and carbonates (r = 0.602), though the siliciclastic correlation is marginally stronger. Thus, even during a time when the Modern EF and siliciclastics are both in the minority, they remain positively correlated in a way that is distinct from the alaeozoic EF. arbonate truncation also appears to affect Modern EF extinction in the alaeozoic, which suggests that both carbonates and siliciclastics may have been important in controlling the macroevolution of the Modern EF, at least during the alaeozoic. 4

5 ULEMENTARY INFRMATIN Extinction rate m g Figure 5: Effect of randomly truncating 60% of the alaeozoic EF genera in epkoskiʼs genus database that span two or more intervals. uncations broke one continuous lineage into two lineages, one with a correct origination but a randomly timed artificial extinction, the other with a correct extinction but a randomly timed artificial origination. epending on where that truncation occurred in time, extinction rates may or may not be altered. Black time series are original, unaltered extinction rates. Red time series shows extinction calculated for the randomly truncated genus data. pearman correlation coefficient for first differences between original and altered genus data is Artificial lineage truncation can only significantly alter short-term patterns of extinction if truncation is non-random with respect to the underlying rates of true lineage extinction and if increases in true rates of extinction do not also increase the probability of genus truncation (that is, the actual extinction of a lineage does not cause an increase in the probability of a genus truncation in epkoskiʼs database). Note that artificial lineage truncation can change the absolute heights of extinction peaks. However, absolute extinction magnitudes are not addressed in this study and, therefore, stretching or compressing the extinction time series will have no quantitative effect on the analyses. 5

6 ULEMENTARY INFRMATIN Figure 6. Geographic distribution of the 541 sampled stratigraphic columns studied here. pacing of points reflects the spatial complexity of the underlying geological record. In regions that have undergone crustal deformation, a greater density of sampling is required in order to completely summarize the rock record. At each location, the compilers of ref. 30 generated a composite stratigraphic summary that includes local variability and subsurface data, generally all the way down to the oldest known crystalline basement rocks. 6

doi: 10.1038/nature07032 ULEMENTARY INFRMATIN Figure 7. imple example of one small portion of one column on one of the 20 correlation charts supplied by ref. 30.

arbonates are shown in blue, fine siliciclastics in grey, and sandstones in yellow. Fine siliciclastic and sandstone are both considered siliciclastic in this study.

7 doi: /nature07032 ULEMENTARY INFRMATIN Figure 7. imple example of one small portion of one column on one of the 20 correlation charts supplied by ref. 30. A single gap-bound package of sediment is shown next to the geologic time scale used on the charts and in this study (see Table 4). Rock types are indicated by the colors of each stratigraphic unit. arbonates are shown in blue, fine siliciclastics in grey, and sandstones in yellow. Fine siliciclastic and sandstone are both considered siliciclastic in this study. In the pictured example, there are two gap-bound packages of carbonate and two gap-bound packages of siliciclastic. The ecorah Fm., for example, has a top and bottom boundary in contact with carbonate packages and the gaps in siliciclastic sedimentation represented by these carbonates constitute environmental gaps, not hiatuses. The top of the upper carbonate package terminates in an unconformity and a standard time-gap hiatus. Note that stratigraphic units on the chart are colored according to the dominant lithology as determined by the field geologists who compiled the charts. Many units have lesser amounts of other lithofacies intercalated within the dominant lithology. uch variability, though unquestionably important, falls below the temporal and spatial resolution of this analysis, just as a population variations among species and genera fall below the biological resolution of epkoskiʼs EFs. 7

8 ULEMENTARY INFRMATIN ART 2: ULEMENTARY TABLE TABLE 1: artial spearman rank-order correlation coefficients showing the correlation between environmental truncation rates and genus extinction when changes in interval length are held statistically constant. ompare to Table 1. alaeozoic EF lithofacies Raw Ext. orr. Ext. NA Ext. arbonate * * * iliciclastic ns ns ns Modern EF lithofacies Raw Ext. orr. Ext. NA Ext. arbonate * ns * ns * iliciclastic ata are de-trended (first differences) time series of genus extinction rates and environmental truncation rates. Raw Ext. refers to face-value extinction rates in epkoski s compendium (Fig. 1B); orr. Ext. refers to extinction rates corrected for variable and incomplete sampling using Foote s optimization procedure 26 (mean rates for 194 pulsed model iterations used); NA Ext. refers to extinction rates using only those genera that occur in North America according to the aleob (~30% of Raw Ext. genera). Rates of truncation for carbonates and siliciclastics are from Figure 3B. ross-correlation for carbonate and siliciclastic is * ns, for alaeozoic and Modern EF *arbonate truncation rates are well-constrained only in the alaeozoic (emadocian-guadalupian; N = 27). The last ermian stage (Tatarian) was omitted because of the low number of carbonate packages in this interval; including it strengthens the correlation between carbonate and the alaeozoic EF (for Raw Ext. r = 0.778). orrelations for siliciclastics are from the emadocian to liocene (N = 62). ns, 0.114; bold,

9 ULEMENTARY INFRMATIN TABLE 2: pearman rank-order correlation coefficients for EF and lithofacies, as in Table 1. In this tabulation, all of epkoskiʼs EF classes, including nektonic classes such as hondrichthyes and Nautiloidea, were included. Lithofacies data remain unchanged from Table 1. aleozoic EF lithofacies Raw. Ext. arbonate * iliciclastic lithofacies arbonate Modern EF Raw. Ext * ns iliciclastic *carbonate rates only defined for aleozoic = ns, = 0.152, bold TABLE 3: Lithofacies assignments in aleobiology atabase. Assigned to carbonates carbonate framestone packstone dolomite bindstone wackestone grainstone bafflestone shale siltstone mudstone sandstone schist siliciclastic tuff bindstone rudstone limestone reef rocks floatstone lime mudstone Assigned to siliciclastics claystone phyllite coal conglomerate slate quartzite volcaniclastic TABLE 4: ummary raw data table used in these analyses. ee separate text file. 9

NAME HOMEWORK ASSIGNMENT #3 MATERIAL COVERS CHAPTERS 8, 9, 10, 11

NAME HOMEWORK ASSIGNMENT #3 MATERIAL OVERS HAPTERS 8, 9, 10, 11 Assignment is due the beginning of the class period on November 23, 2004. Answers for each chapter will be discussed in class, as Exam #3