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Hays, KS, United States

Fort Hays State University is a public, co-educational university located in Hays, Kansas, United States. It is the fourth-largest of the six state universities governed by the Kansas Board of Regents, with an enrollment of approximately 11,200 students . Wikipedia.

Bennett S.C.,Fort Hays State University
Historical Biology | Year: 2013

A previous analysis of the phylogenetic position of the Pterosauria argued that pterosaurs were not closely related to dinosaurs as is generally accepted, but rather were outside the crown group Archosauria. However, that study was dismissed for the use of inappropriate methods. Here, the data set from that analysis was divided into five partitions: one with characters associated with cursorial digitigrade bipedal locomotion and the other four with characters from the skull and mandible, postcranial axial skeleton, forelimb and hindlimb, respectively. The partitions were subjected to homogeneity testing, and the Cursorial partition was found to be incongruent with other partitions and all other characters at the α = 0.01 probability level. Deletion of the Pterosauria removed all significant incongruence, demonstrating that the incongruence results from the coding of pterosaurs for the cursorial characters. The cause of the incongruence was interpreted as homoplasy in hindlimb morphology, and after re-evaluating and reformulating the characters of the Cursorial partition, the revised data set was tested for homogeneity and no significant incongruence was found. Lastly, the data set was updated with additional characters and taxa from recent analyses, tested as before, and when analysed suggested that the Pterosauria were basal archosauriforms well outside the crown group Archosauria. © 2013 Copyright Taylor and Francis Group, LLC.

Maricle B.R.,Fort Hays State University | Adler P.B.,Utah State University
Environmental and Experimental Botany | Year: 2011

In grassland ecosystems, spatial and temporal variability in precipitation is a key driver of species distributions and population dynamics. We experimentally manipulated precipitation to understand the physiological basis for differences in responses of species to water availability in a southern mixed grass prairie. We focused on the performance of two dominant C 4 grasses, Andropogon gerardii Vitman and Schizachyrium scoparium (Michx.) Nash, in treatments that received ambient rainfall, half of ambient rainfall (" drought" treatment), or approximately double ambient rainfall (" irrigated" treatment). Water potentials of S. scoparium were lower than A. gerardii, suggesting superior ability to adjust to water deficit in S. scoparium. Additionally, drought reduced photosynthesis to a greater extent in A. gerardii compared to S. scoparium. Leaf-level photosynthesis rates were similar in ambient and irrigated treatments, but were significantly lower in the drought treatment. Although stomatal conductance was reduced by drought, this was not limiting for photosynthesis. Leaf δ 13C values were decreased by drought, caused by an increase in C i/C a. Chlorophyll fluorescence measures indicated light-harvesting rates were highest in irrigated treatments, and were lower in ambient and drought treatments. Moreover, drought resulted in a greater proportion of absorbed photon energy being lost via thermal pathways. Reductions in photosynthesis came as a result of non-stomatal limitations in the C 4 cycle. Our results provide mechanistic support for the hypothesis that S. scoparium is more drought tolerant than A. gerardii. © 2011 Elsevier B.V.

Bennett S.C.,Fort Hays State University
Neues Jahrbuch fur Geologie und Palaontologie - Abhandlungen | Year: 2013

The holotype specimens of Cycnorhamphus suevicus (Quenstedt, 1855), one of the rarest pterosaur species known from the Upper Jurassic Solnhofen and Nusplingen limestones of southern Germany, and C. canjuersensis (Fabre, 1974), known from a single specimen from roughly contemporary deposits of the Petit Plan de Canjuers, France, are redescribed and their skulls reinterpreted in light on new shape information from a complete isolated skull nicknamed the 'Painten Pelican'. The skulls are quite similar in shape, the holes in the C. canjuersensis mandible that had been interpreted as alveoli are merely artifacts, and differences between the two holotypes are the result of differences in ontogenetic age and quality of preservation. Based on reinterpretation of the two holotypes, C. canjuersensis does not exhibit any features that distinguish it from C. suevicus and so must be considered a junior synonym. © 2012 E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, Germany.

Bennett S.C.,Fort Hays State University
Palaontologische Zeitschrift | Year: 2013

Pterodactylus antiquus has long been thought to have been quite small (~50 cm wingspan) and to have differed from P. longicollum, Ctenochasma, Germanodactylus, and Gnathosaurus in lacking a bony cranial crest, though a soft tissue crest and occipital lappet have been described. This article describes a new specimen of P. antiquus larger than all previously known specimens, which demonstrates that the species exceeded 1 m in wingspan and had a low bony cranial crest. A smaller, incipient crest was identified on the holotype specimen. Additional specimens, including the counterpart of Wellnhofer's original occipital lappet specimen, provide evidence of the occipital lappet and the soft tissue crest extending upward above the naso-antorbital fenestra and orbit. In order to provide a proper taxonomic context for the findings, the recent synonymization of the species Pterodactylus antiquus and P. kochi on the basis of shared correlation of tooth number and skull length despite perceived differences in dentition and skull, neck, and trunk proportions is reviewed. A measurement error that had made it appear that P. antiquus differed significantly from P. kochi in proportions is documented, and after correction of the measurement error and reevaluation of the dental evidence there are no significant differences between the two nominal species. Thus, the synonymization of P. antiquus and P. kochi was appropriate, and a revised diagnosis is presented. In addition, the species P. longicollum and P. micronyx, which for some years have been viewed as not congeneric with P. antiquus, are placed in a new genus and transferred to Aurorazhdarcho, respectively. © 2012 Springer-Verlag Berlin Heidelberg.

Bennett S.C.,Fort Hays State University
Neues Jahrbuch fur Geologie und Palaontologie - Abhandlungen | Year: 2014

A new complete and fully articulated juvenile specimen of the rhamphorhynchoid pterosaur Scaphognathus crassirostris from the Upper Jurassic Solnhofen Limestone of southern Germany is only the third known specimen of the species. The specimen is described and compared to the other two specimens. Based on the comparisons, the skull of Scaphognathus is reinterpreted as having two premaxillary, six maxillary, and five dentary teeth per jaw side, and a broad boat-shaped snout. Scaphognathus is compared to Jianchangnathus robustus, and revised diagnoses of the genus and family are presented. In addition, the position of the cervico-dorsal transition in the vertebral column of pterosaurs is reviewed, and an apparent constraint to nine cervical vertebrae is noted. © 2014 E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, Germany.

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