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Full-Text Articles in Paleobiology
Geometric Morphometric Analysis Of Modern Viperid Vertebrae Facilitates Identification Of Fossil Specimens, Lance D. Jessee
Geometric Morphometric Analysis Of Modern Viperid Vertebrae Facilitates Identification Of Fossil Specimens, Lance D. Jessee
Electronic Theses and Dissertations
Snake vertebrae are common in the fossil record, whereas cranial remains are generally fragile and rare. Consequently, vertebrae are the most commonly studied fossil element of snakes. However, identification of snake vertebrae can be problematic due to extensive variation. This study utilizes 2-D geometric morphometrics and canonical variates analysis to 1) reveal variation between genera and species and 2) classify vertebrae of modern and fossil eastern North American Agkistrodon and Crotalus. The results show that vertebrae of Agkistrodon and Crotalus can reliably be classified to genus and species using these methods. Based on the statistical analyses, four of the …
Distinguishing Mustela From Neogale (Mustelidae) Through Both A Qualitative And Quantitative Analysis Of Skull And Tooth Morphology, Ronald W. Peery
Distinguishing Mustela From Neogale (Mustelidae) Through Both A Qualitative And Quantitative Analysis Of Skull And Tooth Morphology, Ronald W. Peery
Electronic Theses and Dissertations
Weasels and mink (Mustela and Neogale) can be difficult to distinguish osteologically due to similarities in morphology, thus suggesting the need for an accurate tool in distinguishing among taxa. This study utilized a combination of character state and stepwise discriminant function (DFA) analyses to examine potential distinguishing features of skull and tooth morphology. Measurements and ratios were collected from all 18 extant musteline species, as well as the extinct Neovison macrodon, Mustela rexroadensis, Mustela meltoni, Mustela gazini, and Mustela jacksoni. Unidentified musteline specimens from the Gray Fossil Site were also included. Results of …
Manus Descriptions Of An Undescribed Mastodon From The Latest Miocene-Earliest Pliocene Gray Fossil Site, With Comparisons To Other North American Proboscidean Taxa, Brenna Hart-Farrar
Manus Descriptions Of An Undescribed Mastodon From The Latest Miocene-Earliest Pliocene Gray Fossil Site, With Comparisons To Other North American Proboscidean Taxa, Brenna Hart-Farrar
Electronic Theses and Dissertations
A detailed morphological description of a proboscidean manus from the Gray Fossil Site (GFS), Gray, Tennessee is provided. Manus elements from an American mastodon (Mammut americanum), a Britt’s shovel-tusker (Amebelodon britti), an undescribed small gomphothere species, and a Columbian mammoth (Mammuthus columbi) are used for comparisons. Linear measurements indicate proportional differences between the GFS mastodon and other proboscidean taxa ranging from the Hemphillian to Rancholabrean land mammal ages. Possible pathologies are also described. The purpose of this study is to determine how the GFS mastodon differs in manus morphology and locomotion from different proboscidean …
Postcranial Morphology And The Locomotor Adaptations Of Extant And Extinct Crocodylomorphs And Lepidosaurs, Laura Rooney
Postcranial Morphology And The Locomotor Adaptations Of Extant And Extinct Crocodylomorphs And Lepidosaurs, Laura Rooney
Electronic Theses and Dissertations
I have collected a series of linear measurements of the postcranial skeletons of 43 extant crocodylian and lepidosaur taxa to determine if those engaging in similar locomotor behavior display similar morphology despite phylogenetic differences. Stepwise discriminant function analyses reveal reptile locomotor mode can be accurately predicted (over 80% correct) based on morphology. Semi-aquatic taxa are distinguished by a longer ischium relative to pubis length, a longer scapula relative to humerus length, and a broader acetabulum than terrestrial and arboreal taxa. Arboreal taxa display a more elongate, gracile humerus and a smaller acetabulum. This morphometric data can potentially be used to …
A New Species Of Teleoceras From The Late Miocene Gray Fossil Site, With Comparisons To Other North American Hemphillian Species, Rachel A. Short
A New Species Of Teleoceras From The Late Miocene Gray Fossil Site, With Comparisons To Other North American Hemphillian Species, Rachel A. Short
Electronic Theses and Dissertations
A thorough morphological description of Teleoceras material from the Gray Fossil Site, Gray, Tennessee is provided. This is the only record of a browsing Teleoceras and, as a late Hemphillian locality, represents one of the youngest populations. Linear measurements of post-cranial elements indicate proportional differences between Teleoceras from the Gray Fossil Site and those from other Hemphillian localities. These differences are more pronounced in the elements of the forelimb than in those of the hind limb. Statistical analyses of post-cranial elements from 3 Hemphillian species of Teleoceras suggest that these differences should not be used to separate species. However, the …
Extreme Variation In The Sagittal Crest Of Tapirus Polkensis (Mammalia Perissodactyla) At The Gray Fossil Site Northeastern Tn., Aaron Randall Abernethy
Extreme Variation In The Sagittal Crest Of Tapirus Polkensis (Mammalia Perissodactyla) At The Gray Fossil Site Northeastern Tn., Aaron Randall Abernethy
Electronic Theses and Dissertations
The preservation and quantity of fossil tapirs (Tapirus polkensis) from the Gray Fossil Site in northeastern Tennessee provides a unique opportunity for comparison and analysis of skeletal characters. Intraspecifically, modern tapirs show little to no variation in the morphology of the sagittal crest. However, several different morphologies exist within the sample at Gray. No osteological evidence of sexual dimorphism exists for tapirs, and no correlation between crest shape and sex was observed. Several juveniles display well defined crests, while some adults have only minor thickening of the temporal ridges; therefore, no distinct correlation between age and crest state …
Vitis Seeds (Vitaceae) From The Late Neogene Gray Fossil Site, Northeastern Tennessee, Usa., Fade Gong
Vitis Seeds (Vitaceae) From The Late Neogene Gray Fossil Site, Northeastern Tennessee, Usa., Fade Gong
Electronic Theses and Dissertations
This study focuses on the morphometric and systematic studies of fossil vitaceous seeds recently recovered from the Gray Fossil Site (7-4.5 Ma, latest Miocene-earliest Pliocene) northeastern Tennessee. Morphologically, all fossil seeds correspond to the extant subgenus Vitis (genus Vitis) of the Vitaceae based on the smooth dorsal surface with a centrally positioned chalaza connected with a conspicuous chalaza-apex groove and short linear ventral infolds that are slightly diverged apically. A multivariate analysis based on 11 measured characters from 76 complete seeds identified three types of seeds, each representing a distinct morphotaxon. Based on comparison with modern and fossil vitaceous …
A Phylogenetic Analysis Of Species Relationships In Hemlocks, The Genus Tsuga (Pinaceae)., Jordan David Baker
A Phylogenetic Analysis Of Species Relationships In Hemlocks, The Genus Tsuga (Pinaceae)., Jordan David Baker
Electronic Theses and Dissertations
The genus Tsuga is comprised of eight extant species found in North America and East Asia and four species represented by fossils from Europe and Japan. This study presents the first phylogenetic analysis based on structural, biochemical, and molecular sequence data. Characters obtained from published and unpublished literature were combined with new morphological characters from seeds, seedlings, and leaf cuticle material. Results from parsimony analyses of these characters differed from the published molecular based phylogeny. The non-molecular based phylogeny resolves two separate clades, a North American and an Asian, but did not group the western North American species, as in …