Trachemys (Testudines: Emydidae) represents one of the most well-known turtles today. The evolution of Trachemys, while being heavily documented with various fossil representatives, is not well understood. Numerous fossils from the Gray Fossil Site in northeastern Tennessee are helping to elucidate the taxon’s evolution. The fossil Trachemys at the Gray Fossil Site represent a new species. A review of previously named Trachemys taxa reveals that a huge majority of them are not valid or have been previously misinterpreted. A phylogenetic analysis preformed on modern emydids and supposed fossil representatives of those genera also shows the evolution of a portion of the modern turtle fauna. While some fossils are nested within modern clades, a large number of the fossil turtles studied fall within their own clade. This may mean that these fossils represent an extinct lineage and less fossil representatives of modern turtles are known than previously thought.
","abstract_html":"<p><em>Trachemys</em> (Testudines: Emydidae) represents one of the most well-known turtles today. The evolution of <em>Trachemys</em>, while being heavily documented with various fossil representatives, is not well understood. Numerous fossils from the Gray Fossil Site in northeastern Tennessee are helping to elucidate the taxon’s evolution. The fossil <em>Trachemys</em> at the Gray Fossil Site represent a new species. A review of previously named <em>Trachemys</em> taxa reveals that a huge majority of them are not valid or have been previously misinterpreted. A phylogenetic analysis preformed on modern emydids and supposed fossil representatives of those genera also shows the evolution of a portion of the modern turtle fauna. While some fossils are nested within modern clades, a large number of the fossil turtles studied fall within their own clade. This may mean that these fossils represent an extinct lineage and less fossil representatives of modern turtles are known than previously thought.</p>","abstract_has_math":false,"creators":["Jasinski, Steven E."],"institution":null,"degree_name":"MS (Master of Science)","degree_level":"Thesis - unrestricted","degree_discipline":"Biology","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2013,"date_issued":"2013-05-01T07:00:00Z","date_published":"2013-05-01T07:00:00Z","updated_at":"2026-07-24T02:20:06Z","subjects":["turtle","Gray Fossil Site","phylogeny","taxonomy","morphology","osteology","Biology","Life Sciences"],"languages":[],"rights":["Copyright by the authors."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://dc.etsu.edu/etd/1231","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Jasinski, Steven E."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2014-07-01T07:00:00Z"]},{"key":"dc:date.issued","label":"Date","values":["2013-05-01T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis - unrestricted"]},{"key":"thesis:degree_name","label":"Degree Name","values":["MS (Master of Science)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["turtle","Gray Fossil Site","phylogeny","taxonomy","morphology","osteology","Biology","Life Sciences"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["Copyright by the authors."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://dc.etsu.edu/context/etd/article/2417/viewcontent/JasinskiS010813f.pdf","https://dc.etsu.edu/etd/1231"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Trachemys (Testudines: Emydidae) represents one of the most well-known turtles today. The evolution of Trachemys, while being heavily documented with various fossil representatives, is not well understood. Numerous fossils from the Gray Fossil Site in northeastern Tennessee are helping to elucidate the taxon’s evolution. The fossil Trachemys at the Gray Fossil Site represent a new species. A review of previously named Trachemys taxa reveals that a huge majority of them are not valid or have been previously misinterpreted. A phylogenetic analysis preformed on modern emydids and supposed fossil representatives of those genera also shows the evolution of a portion of the modern turtle fauna. While some fossils are nested within modern clades, a large number of the fossil turtles studied fall within their own clade. This may mean that these fossils represent an extinct lineage and less fossil representatives of modern turtles are known than previously thought.
"]},{"key":"dc:title","label":"Title","values":["Fossil Trachemys (Testudines: Emydidae) from the Late Hemphillian of Eastern Tennessee and Its Implications for the Evolution of the Emydidae"]}]}],"canonical_facts":{"dc:creator":["Jasinski, Steven E."],"dc:date.available":["2014-07-01T07:00:00Z"],"dc:date.issued":["2013-05-01T07:00:00Z"],"dc:description.abstract":["Trachemys (Testudines: Emydidae) represents one of the most well-known turtles today. The evolution of Trachemys, while being heavily documented with various fossil representatives, is not well understood. Numerous fossils from the Gray Fossil Site in northeastern Tennessee are helping to elucidate the taxon’s evolution. The fossil Trachemys at the Gray Fossil Site represent a new species. A review of previously named Trachemys taxa reveals that a huge majority of them are not valid or have been previously misinterpreted. A phylogenetic analysis preformed on modern emydids and supposed fossil representatives of those genera also shows the evolution of a portion of the modern turtle fauna. While some fossils are nested within modern clades, a large number of the fossil turtles studied fall within their own clade. This may mean that these fossils represent an extinct lineage and less fossil representatives of modern turtles are known than previously thought.
"],"dc:identifier":["https://dc.etsu.edu/context/etd/article/2417/viewcontent/JasinskiS010813f.pdf","https://dc.etsu.edu/etd/1231"],"dc:rights":["Copyright by the authors."],"dc:subject":["turtle","Gray Fossil Site","phylogeny","taxonomy","morphology","osteology","Biology","Life Sciences"],"dc:title":["Fossil Trachemys (Testudines: Emydidae) from the Late Hemphillian of Eastern Tennessee and Its Implications for the Evolution of the Emydidae"],"thesis:degree_discipline":["Biology"],"thesis:degree_level":["Thesis - unrestricted"],"thesis:degree_name":["MS (Master of Science)"]},"updated_at":"2026-07-24T02:20:06Z"}