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A skeleton of a new ceratopsid dinosaur, Eotriceratops xerinsularis gen. et sp. nov., is described in this paper. It is the first associated vertebrate skeleton found within the upper 20 m of the Horseshoe Canyon Formation. Eotriceratops xerinsularis is a large chasmosaurine that differs from other chasmosaurines in a unique set of features in the premaxilla, nasal horn core, squamosal frill, and epijugal. The most striking of those features includes an extremely tall, non-recessed narial process of the premaxilla; the presence of greatly elongate, spindle-shaped epoccipitals on the squamosal frill; a deep, well-demarcated fossa on the anteroventral surface of the squamosal frill; a sharply conical epijugal with a pronounced proximoposterior process and separate fossa-like facets for the jugal and quadratojugal; and the presence of an obliquely extending vascular trace meeting a transverse vascular trace ventrally on the anterior surface of the nasal horn core. Our phylogenetic analysis suggests that E. xerinsularis is nested within a clade including Triceratops, Diceratops, and Torosaurus, which are all from late Maastrichtian deposits. The upper 20 m of the Horseshoe Canyon Formation comprises a coal-rich interval (Carbon–Thompson coal zone, unit 5), which previously has been assigned to upper Maastrichtian magnetochrons 31n and 30r, and the Mancicorpus gibbus miospore subzone. The ceratopsid specimen was collected from between the Carbon and Thompson coal seams, and thus, is inferred to (1) occur near the top of magnetochron 31n and (2) have an age of 67.6–68.0 Ma. Large chasmosaurine ceratopsids, such as Triceratops and Torosaurus, have not previously been described from the Horseshoe Canyon Formation or from magnetochron 31n or the M. gibbus miospore subzone. Thus, Eotriceratops is distinctly older than any other ceratopsid in the Triceratops group, and the discovery of E. xerinsularis helps fill a biostratigraphic gap between early and late Maastrichtian chasmosaurines. [ABSTRACT FROM AUTHOR]

Recent archaeological excavations at a deeply stratified site in northwest Calgary, Alberta have uncovered four occupation layers spanning the interval from 8000 to 2000 BP. Depending on the dating one accepts for the Holocene thermal maximum, two or more of these occupations occurred during this interval of aridity. This site thus provides a record of human occupation during the Archaic (Middle Prehistoric I) period in the Calgary area. More importantly, the site occurs in an upland setting, apparently far removed from reliable sources of water and normal environments of deposition. Yet, the cultural deposits occur in sediments which extend 2 m below surface and include five sedimentary units as well as a minimum of three pedogenic units. This paper presents the results of geoarchaeological research on the changing landscape for the site and notes the implications of these changes for the study of Archaic manifestations on the northern Plains. [ABSTRACT FROM AUTHOR]