ENVIRONMENTAL AND TEMPORAL PATTERNS IN PLANT DIVERSITY THROUGH GEOLOGIC TIME
PI's: Hallie J. Sims, Patricia G. Gensel, and Scott L. Wing
Plants first appeared on land roughly 410 million years ago. Since then, there clearly has been a massive increase in the number of plant species, the spatial complexity of terrestrial vegetation, and the range of habitats that plants occupy. The taxonomic composition of terrestrial vegetation also has changed completely. Although major trends and events affecting terrestrial plants have long been identified in a descriptive way and quantitative data exist for many local sites and short time intervals, there has been only one attempt to quantify the major Phanerozoic trends in plant diversity and floral composition. Recent advances in the statistical analysis of diversity data, increasing recognition of the importance of spatial scale for interpreting diversity data, and growing acceptance of bioinformatic databases as important tools for maximizing the value of published data, make this the right time for a new quantification of long-term trends in the ecology of terrestrial plants. We have formed a working group of fifteen paleobotanists whose specialties span the temporal and biological spectrum to collect high-quality data on Silurian to Paleogene fossil plant localities, occurrences, and taxa as part of the Paleobiology Database (http://flatpebble.nceas.ucsb.edu/public/). The result will be a public, web-based repository for fossil occurrence data- a "GenBank" for the plant fossil record. With these data, we will assess the effects of sampling biases on changes in estimated global plant diversity, examine environmental correlates of diversity change, and track changes in diversity at local, regional, and global scales.
