THALASSINOIDES ISP. BURROW ORIENTATION IN THE CRETACEOUS WESTERN INTERIOR SEAWAY: A STATISTICAL TEST

Statistical trends in the orientation of Thalassinoides isp. burrows were tested at an outcrop of the Glen Rose Formation exposed by Cow House Creek in Coryell County, Texas, USA. Burrow orientations were analyzed using digital landmarks, creating vectors characterizing length and orientation relative to north on a horizontal plane. These were plotted as a rose diagram to better visualize any inherent trends and were further analyzed using PAST to provide evidence for preferred orientations via chi-square test. It is hypothesized that these burrows may demonstrate a collective behavior, reflective of traces exhibited by the recent analogs Upogebia pusilla, Upogebia africana, and Jaxea nocturna. Confirmation of these trends and how they relate to their environment would be important to the understanding of thalassinid shrimp ecology and prove a valuable aid to paleo-oceanographic modeling.