. Bulletins of American paleontology. -200 -100 0 100 200 300 400 500 AXIS 3. -200 -100 100 200 300 400 500 AXIS 2 10 I 0) E 8 6 4 â 2 0 II â E DL -200 -100 0 100 200 300 400 500 AXIS 3 Text-figure 11.âHistograms of DCA scores for species determined using relative abundance code data. The analysis is the same as Text- fig. 10. Species are grouped by colony shape (left side) and by survivorship (right side), 'b'. branching; 'm', massive; 'p', platy, "E", extinct; 'L". living. the two clusters of Lomas del Mar localities is less distinct, and (2) there is less overlap among the Sa
. Bulletins of American paleontology. -200 -100 0 100 200 300 400 500 AXIS 3. -200 -100 100 200 300 400 500 AXIS 2 10 I 0) E 8 6 4 â 2 0 II â E DL -200 -100 0 100 200 300 400 500 AXIS 3 Text-figure 11.âHistograms of DCA scores for species determined using relative abundance code data. The analysis is the same as Text- fig. 10. Species are grouped by colony shape (left side) and by survivorship (right side), 'b'. branching; 'm', massive; 'p', platy, "E", extinct; 'L". living. the two clusters of Lomas del Mar localities is less distinct, and (2) there is less overlap among the Santa Rosa and Buenos Aires localities. Even with these ex- ceptions, axis 1 still appears to be related to time. The distribution of localities along axis 2, however, is somewhat different from the relative abundance re- sults; the two stratigraphically older localities (BS, C4) no longer have relatively high values, localities with more massive species are no longer distinct from lo- calities with more platy species, and the two localities in the Buenos Aires Pontes thickets (BAl, BA4) are separated from the others by a large gap. Thus axis 2 appears to distinguish the two nearshore environments but is less clearly related to exposure. As in the relative abundance results, axis 3 is uninterpretable. In order to better understand how the 10 tightly clustering localities from the Lomas del Mar trend af- fected the results, a final analysis was performed after these 10 localities were removed. The analysis was run using relative abundance codes. The results (Text-fig. 12b) show even stronger overlap among the Buenos Aires, Santa Rosa, and three remaining Lomas del Mar localities along axis 1 as well as considerable overlap among the Buenos Aires and Santa Rosa localities along axis 2. Thus, as in the cluster analysis results, the assemblages appear to intergrade, and although variation among assemblages appears to be coarsely related to evolution and environment, more refined r
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