|North-Central Section - 35th Annual Meeting (April 23-24, 2001)|
|Paper No. 15-0|
|Presentation Time: 9:20 AM-9:40 AM|
AN EXAMINATION OF THE PHYLOGENETIC POSITION OF THE EMBOLOMERI
GARCIA, William J., Department of Geology, Univ of Cincinnati, 500 Geology/Physics Building, Cincinnati, OH 45221, firstname.lastname@example.org|
Recent phylogenetic studies of early tetrapods have produced phylogenies that contradict the traditional belief that anthracosaurs are the sister group to amniotes while temnospondyls are the sister group to the lissamphibia. In order to test the monophyly of the Embolomeri, a group of Carboniferous and Permian anthracosaurs, additional embolomeres were added to the data matrix of Laurin (1998) and coded based upon published descriptions. Added to the database were the following embolomere taxa: Anthracosaurus, Carbonerpeton, Calligenethlon, Eoherpeton, Palaeogyrinus, Pholiderpeton, and Pteroplax. The resulting data set contained 52 taxa and 155 characters, thirteen of which are anthracosaurs under the traditional definition. The heuristic algorithm of PAUP* (Swofford, 1999) produced 6 most parsimonious trees from this dataset. The Adams consensus tree produced from the most parsimonious trees contains a monophyletic clade containing both the Embolomeri and the Gephyrostegidae. Excluded from this clade are the seymouriamorphs, the third group traditionally included within the Anthracosauria. Instead the seymouriamorphs are included within a larger clade that includes both amniotes and extant amphibians. The combined Emobolmeri and Gephyrostegidae is a sister group to this larger amniote, amphibian, and seymouriamorph clade. This relationship is not robustly supported, one thousand bootstrap replicates produced confidence values below 50 percent for the embolomere + gephyrostegid clade. Removal of embolomere taxa with significant percentages of missing data did not increase support in a second bootstrap.
North-Central Section - 35th Annual Meeting (April 23-24, 2001)
General Information for this Meeting
|Session No. 15|
Bowling and Billiards Center, Illinois State University: BBC Activity Room
8:20 AM-11:00 AM, Tuesday, 24 April 2001
Geological Society of America Abstracts with Programs, Vol. 33, No. 4, March 2001, p. 23
© Copyright 2001 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.