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Found 2 essays matching the above criteria.

1. 1. Dynamics of Selachian (Shark) Dental Morphology During the Early Mesozoic

   University essay from Uppsala universitet/Institutionen för geovetenskaper

   Author : Alexander Paxinos; [2017]
   Keywords : Early Mesozoic; Selachii; morphological disparity; geometric morphometrics; early radiation; Tidig Mesozoisk; Selachimorpha; morfologisk disparitet; geometrisk morfometri; tidig strålning;

   Abstract : The ancestors of all modern day sharks and rays (Neoselachii) may have appeared during the Late Palaeozoic, but their major diversification happened sometime during the Early Mesozoic. Taxonomic evidence places the first neoselachian diversification in the Early Jurassic. READ MORE

3. 2. Disparity of Early Cretaceous Lamniformes sharks

   University essay from Uppsala universitet/Institutionen för geovetenskaper

   Author : Fredrik Söderblom; [2015]
   Keywords : Lamniformes; disparity; Early Cretaceous; morphology; morphometric; Lamniformes; disparitet; tidig krita; morfologi; morfometri;

   Abstract : The geological range of lamniform sharks stretches from present day species such as Carcharodon carcharias (great white shark) back to the at the moment oldest undoubted fossil finds during the Early Cretaceous. In this paper a geometric morphometric analysis was performed on images of Early Cretaceous lamniform teeth collected from published literature in order to examine the change in disparity (range of morphological variation within a group) throughout the time period. READ MORE