Although predator-prey escalation has been well documented in molluscan ecological systems, relatively little is known about what occurs after these systems have escalated. In order to assess potential changes in already-escalated systems, we examined bulk samples of Turritella shells collected from Neogene strata of the Atlantic and Gulf Coastal Plain, U.S.A. In particular, we examined the intensity, efficiency, and stereotypy of naticid and muricid predation on Turritella as a means of discerning subtle changes in predatory behavior. As in previous studies, we observe little change in the intensity and efficiency of naticid and muricid predation on Turritella during the Neogene. Unlike previous studies, we note significant changes in prey size during this interval. Perhaps more significant is that these changes are associated with concomitant changes in predatory drilling behavior as expressed in drillhole-site selectivity and prey-size selectivity. Together, these findings suggest that escalation was still occurring in this Neogene system, with predators likely making behavioral changes in order to keep pace with morphologic changes occurring within prey populations.