U-Th dating of Holocene age Acropora prolifera (Lamarck, 1816) colonies confirms coral hybridization is not a recent phenomenon.

Abstract. To confirm previous findings that hybridization of Caribbean acroporid corals occurred in the recent geologic past, we determined the uranium-thorium (U-Th) ages of two subfossil Acropora prolifera samples collected from nearshore coral death assemblages located off the coast of southeastern Florida. Our results indicate that A, prolifera existed in southeastern Florida during the late Holocene, confirming that Caribbean acroporid hybridization occurred prior to their region-wide die off in the 1970s and 1980s.