i1 Ecological Sorting of Vascular Plant Classes During the Paleozoic Evolutionary Radiation

ferns, sphenopsids, seed plants), corresponding roughly to traditional Linnean classes, originated in a radiation that began in the late Middle Devonian and ended in the Early Carboniferous. This relatively brief radiation followed a long period in the Silurian and Early Devonian during wrhich morphological complexity accrued slowly and preceded evolutionary diversifications con-fined within major body-plan themes during the Carboniferous. During the Middle Devonian-Early Carboniferous morphological radiation, the major class-level clades also became differentiated ecologically: Lycopsids were cen-tered in wetlands, seed plants in terra firma environments, sphenopsids in aggradational habitats, and ferns in disturbed environments. The strong con-gruence of phylogenetic pattern, morphological differentiation, and clade-level ecological distributions characterizes plant ecological and evolutionary dynamics throughout much of the late Paleozoic. In this study, we explore the phylogenetic relationships and realized ecomorphospace of reconstructed whole plants (or composite whole plants), representing each of the majo