A phylogenetic test of accelerated turnover in Neogene Caribbean brain corals (Scleractinia : Faviidae)

Documenting patterns of long-term faunal change is an important application of palaeontological data, but questionable results may be obtained if the potential effects of sampling bias are not considered. Analysis of fossil C aribbean reef coral occurrences indicates significant species turnover duri ng the late Neogene. The goal of this study is to test this pattern for a s ubset of the entire fauna by using phylogenetic information to identify pro blematical taxa and periods of poor sampling. A phylogeny for 40 species fr om the faviid genera Caulastraea, Colpophyllia, Diploria, Favia, Hanrophyll ia, Manicina and Thysanus was inferred using 23 multistate characters. Alth ough the relationships are homoplasious, some stable groups emerged. One gr oup includes the Colpophyllia species, another includes Manicina, Hadrophyl lia and Thysanus species. As currently defined, both Favia and Diploria are paraphyletic stem groups. The inferred evolutionary tree was used to estim ate species richness and proportional origination and extinction rates. Whe n ghost lineages are considered, the magnitude of species richness estimate s increases resulting in lower estimates of proportional origination and ex tinction. However, the pattern of faunal change within the group remains la rgely unchanged, with increased origination during the Late Miocene followe d by extinction during the Late Pliocene and early Pleistocene.