The effects of lineage age on the species richness of regional assemblages

• Patrick R. Stephens

Abstract
Like area, time is a factor that must constrain diversity at some level, yet very little is known about how time and species richness are related in most groups. It was widely accepted during the first half of the 20th century that time constrained diversity in many groups, though there was little direct evidence for this. Ironically, interest in the relationship waned just before the phylogenetic tools necessary to investigate it directly it were developed. I propose to investigate the relationship between the relative age and species richness of regional assemblages in a wide variety of organisms.