Anthozoan cnidarians (>7500 species) are arguably one of the most ecologically important groups of metazoans on earth. By their ability to produce large colonies by asexual propagation and CaCO3 precipitation, some species create massive biogenic structures, thereby engineering entire reef-based ecosystems in both shallow and deep waters. Countless other species—including humans—are dependent on coral reefs for shelter and sustenance. Predictions that increases in atmospheric CO2 leading to ocean acidification (OA) and warmer ocean temperatures will impact skeletogenesis have generated widespread concern about the future of reef-building anthozoans and the diverse communities they support.  Increased understanding of past evolutionary transitions in skeletal composition and of the paleoclimatic variables associated with the loss or gain of CaCO3 skeletons will inform predictions of future change.  For example, whether or not soft-bodied anthozoans such as Corallimorpharia (coral-like anemones) were indeed derived by skeletal loss during past environmental crises remains controversial. This question is one of many that cannot currently be answered due to our incomplete understanding of phylogenetic relationships among anthozoan orders. A robust, well-resolved phylogeny of Anthozoa is required in order to test hypotheses of skeletal evolution and other key characters that have lead to the success of the class.


Photo Credits; C. McFadden and the NOAA Okeanos Explorer Program

This material is based upon work supported by the National Science Foundation under Grant Number NSF DEB 1457817 ​

Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation