A new look at age and area: the geographic and environmental expansion of genera during the Ordovician Radiation

摘要: Although available paleobiological data indicate that the geographic ranges of marine species are maintained throughout their entire observable durations, other evidence suggests, by contrast, higher taxa expand as they age, perhaps in association with increased richness. Here, I utilize a database Ordovician genus occurrences collected from literature for several paleocontinents to demonstrate significant aging global biota during Radiation was accompanied and environmental expansion ranges. The proportion genera occurring two or more database, zones within six-zone onshore-offshore framework, significantly Caradocian Ashgillian. Moreover, widespread tended be older than endemic counterparts, suggesting direct link between ages extents. Expansion corroborated further demonstrating this pattern directly among ranged Tremadocian through Taken together, these results not only what reveal about kinetics major, global-scale diversification, but also suggest interpretation relationships diversity trends at alpha (within-community) beta (between-community) levels.