REBUILDING REEFS AFTER REEF CRISES -- THE EXTINCTION OF PHANEROZOIC REEF TAXA, AND VARIABLE PERSISTENCE OF HABITAT PREFERENCE AMONG SURVIVORS

Episodes of reef crisis, defined by significant loss in the volume of reefal carbonate rock, are associated with dramatic turnover in clades of reef-builders, but little attention has been directed to other reef dwellers during these episodes. Do they exhibit the same extinction dynamics, or do they have greater flexibility of preferred habitat (eurytopy), allowing them to evade extinction? Do they exhibit the same post-crisis incumbency effects as reef-builders? To explore these questions, stage-level occurrences of 24,028 marine invertebrate genera, differentiated as reef builders, reef dwellers, and non-reefal, were compared during elevenreef crises and intervening background intervals through the Phanerozoic. I find that reef genera often feature lower extinction rates than nonreefal genera, potentially tied to a more eurytopic habit than nonreefal genera. There is also a stronger persistence of reef habitat preference among reef-builders than reef-dwellers, but inconsistent responses in extinction. Reef crises are often tied to greater extinction of reef taxa, particularly reef builders, but reef crises and non-crisis intervals that are not otherwise linked to mass extinction events do not show significant difference between reef-builders and reef-dwellers. These results suggest Phanerozoic reefal genera are less susceptible to extinction than non-reefal genera, and that the reef-dwellers and reef-builders exhibit different levels of persistence in occupation of reefal habitat. However, that difference may not strongly impact susceptibility to extinction.