Phylogeny and evolutionary history of diplobathrid crinoids (Echinodermata) |
| |
Authors: | Selina R Cole |
| |
Institution: | 1. Division of Paleontology, American Museum of Natural History, Central Park West at 79th St., New York, NY, 10024 USA;2. Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, PO Box 3. 37012, MRC 121, Washington, DC, 20013‐7012 USA |
| |
Abstract: | Order Diplobathrida is a major clade of camerate crinoids spanning the Ordovician–Mississippian, yet phylogenetic relationships have only been inferred for Ordovician taxa. This has hampered efforts to construct a comprehensive tree of life for crinoids and develop a classification scheme that adequately reflects diplobathrid evolutionary history. Here, I apply maximum parsimony and Bayesian phylogenetic approaches to the fossil record of diplobathrids to infer the largest tree of fossil crinoids to date, with over 100 genera included. Recovered trees provide a framework for evaluating the current classification of diplobathrids. Notably, previous suborder divisions are not supported, and superfamily divisions will require significant modification. Although numerous revisions are required for families, most can be retained through reassignment of genera. In addition, recovered trees were used to produce phylogeny‐based estimates of diplobathrid lineage diversity. By accounting for ghost lineages, phylogeny‐based richness estimates offer greater insight into diversification and extinction dynamics than traditional taxonomy‐based approaches alone and provide a detailed summary of the ~150 million‐year evolutionary history of Diplobathrida. This study constitutes a major step toward producing a phylogeny of the Crinoidea and documenting crinoid diversity dynamics. In addition, it will serve as a framework for subsequent phylogeny‐based investigations of macroevolutionary questions. |
| |
Keywords: | phylogeny Diplobathrida Crinoidea systematics diversification macroevolution |
|
|