{"id":{"repo_id":"lsu-thes","oai_identifier":"oai:repository.lsu.edu:gradschool_dissertations-2287"},"canonical_url":"https://search.dev.ndltd.org/etd/lsu-thes/oai:repository.lsu.edu:gradschool_dissertations-2287","repository":{"repo_id":"lsu-thes","name":"Lousiana State University","base_url":"https://repository.lsu.edu/do/oai/"},"display":{"title":"Miocene herpetofaunas from the central Gulf Coast USA: their paleoecology, biogeography, and biostratigraphy","abstract":"The late Barstovian Fort Polk herpetofauna represents the most diverse herpetofauna on the Gulf Coast, USA, and includes 15 genera from ten families. The herpetofaunal composition of Fort Polk and Miocene east Texas localities is similar enough to Great Plains localities that they are all considered to be one biogeographical province during the Barstovian. The use of ternary diagrams, ratios of herpetological elements to kg matrix screened, and natricine-colubrine indices, has allowed determining the wetness of the Fort Polk sites. Development of a composite stratigraphic section for North American fossil snakes has allowed recognition of two extinctions of fossil snakes during the Miocene. North American and European Miocene snake faunas display a replacement of boids by colubrids in the Early to Middle Miocene and Late Oligocene, respectively. European fossil snake data show a decrease in colubrid numbers from the Early to Middle Miocene.","abstract_html":"The late Barstovian Fort Polk herpetofauna represents the most diverse herpetofauna on the Gulf Coast, USA, and includes 15 genera from ten families. The herpetofaunal composition of Fort Polk and Miocene east Texas localities is similar enough to Great Plains localities that they are all considered to be one biogeographical province during the Barstovian. The use of ternary diagrams, ratios of herpetological elements to kg matrix screened, and natricine-colubrine indices, has allowed determining the wetness of the Fort Polk sites. Development of a composite stratigraphic section for North American fossil snakes has allowed recognition of two extinctions of fossil snakes during the Miocene. North American and European Miocene snake faunas display a replacement of boids by colubrids in the Early to Middle Miocene and Late Oligocene, respectively. European fossil snake data show a decrease in colubrid numbers from the Early to Middle Miocene.","abstract_has_math":false,"creators":["Williams, Michael John"],"institution":"Geology and Geophysics","degree_name":"Doctor of Philosophy (PhD)","degree_level":"Dissertation","degree_discipline":"Earth Sciences","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009-01-01T08:00:00Z","date_published":"2009-01-01T08:00:00Z","updated_at":"2026-07-24T02:59:22Z","subjects":["salamander","fossil","Hemphillian","Hemingfordian","Arikareean","frog"],"languages":[],"rights":["unrestricted","Release the entire work immediately for access worldwide."],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["etd-11132009-034120","https://repository.lsu.edu/gradschool_dissertations/1288"],"render_values":[{"text":"etd-11132009-034120","href":null,"code":true},{"text":"https://repository.lsu.edu/gradschool_dissertations/1288","href":"https://repository.lsu.edu/gradschool_dissertations/1288","code":true}]}]},"links":{"outbound_url":"https://doi.org/10.31390/gradschool_dissertations.1288","outbound_label":"DOI","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Williams, Michael John"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2009-10-29"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2022-05-12T23:11:38Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Earth Sciences"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Doctor of Philosophy (PhD)"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Geology and Geophysics"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["salamander","fossil","Hemphillian","Hemingfordian","Arikareean","frog"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["unrestricted","Release the entire work immediately for access worldwide."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["etd-11132009-034120","10.31390/gradschool_dissertations.1288","https://repository.lsu.edu/gradschool_dissertations/1288"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The late Barstovian Fort Polk herpetofauna represents the most diverse herpetofauna on the Gulf Coast, USA, and includes 15 genera from ten families. The herpetofaunal composition of Fort Polk and Miocene east Texas localities is similar enough to Great Plains localities that they are all considered to be one biogeographical province during the Barstovian. The use of ternary diagrams, ratios of herpetological elements to kg matrix screened, and natricine-colubrine indices, has allowed determining the wetness of the Fort Polk sites. Development of a composite stratigraphic section for North American fossil snakes has allowed recognition of two extinctions of fossil snakes during the Miocene. North American and European Miocene snake faunas display a replacement of boids by colubrids in the Early to Middle Miocene and Late Oligocene, respectively. European fossil snake data show a decrease in colubrid numbers from the Early to Middle Miocene."]},{"key":"dc:title","label":"Title","values":["Miocene herpetofaunas from the central Gulf Coast USA: their paleoecology, biogeography, and biostratigraphy"]}]}],"canonical_facts":{"dc:creator":["Williams, Michael John"],"dc:date":["2009-10-29"],"dc:date.available":["2022-05-12T23:11:38Z"],"dc:description.abstract":["The late Barstovian Fort Polk herpetofauna represents the most diverse herpetofauna on the Gulf Coast, USA, and includes 15 genera from ten families. The herpetofaunal composition of Fort Polk and Miocene east Texas localities is similar enough to Great Plains localities that they are all considered to be one biogeographical province during the Barstovian. The use of ternary diagrams, ratios of herpetological elements to kg matrix screened, and natricine-colubrine indices, has allowed determining the wetness of the Fort Polk sites. Development of a composite stratigraphic section for North American fossil snakes has allowed recognition of two extinctions of fossil snakes during the Miocene. North American and European Miocene snake faunas display a replacement of boids by colubrids in the Early to Middle Miocene and Late Oligocene, respectively. European fossil snake data show a decrease in colubrid numbers from the Early to Middle Miocene."],"dc:identifier":["etd-11132009-034120","10.31390/gradschool_dissertations.1288","https://repository.lsu.edu/gradschool_dissertations/1288"],"dc:rights":["unrestricted","Release the entire work immediately for access worldwide."],"dc:subject":["salamander","fossil","Hemphillian","Hemingfordian","Arikareean","frog"],"dc:title":["Miocene herpetofaunas from the central Gulf Coast USA: their paleoecology, biogeography, and biostratigraphy"],"thesis:degree_discipline":["Earth Sciences"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Doctor of Philosophy (PhD)"],"thesis:institution_name":["Geology and Geophysics"]},"updated_at":"2026-07-24T02:59:22Z"}