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In this study progradation of the dune toe on the sandy, dune-backed beaches of Makah Bay, on the Pacific Ocean shorelines of the reservation lands of the Makah Tribe, were documented for the first time. A shoreline assessment was implemented that included repeat beach profile surveys using RTK-DGPS and aerial lidar, and historical change analysis using aerial photos. Analysis of GNSS and aerial lidar suggest patterns of dune toe progradation over the last decade at average rates of ~0.8 m/yr between 2010 and 2022 over almost all the 5.5 km length of beach in Makah Bay, excepting the ~250m long erosional area that prompted the study. A beach vegetation line delineated in aerial photos collected between 1952 and 2019 moved seaward at average rates of ~0.7 m/yr across the entire length of Makah Bay, suggesting that the pattern of progradation is long-lived. We assess evidence to evaluate whether this pattern of dune progradation can be explained by sediment supplies from watersheds draining to Makah Bay and conclude that local sediment supply cannot explain observed patterns. A variety of shoreline processes associated with relative sea-level fall are discussed and may explain the observed rates of shoreline progradation. 

The end-Cretaceous mass extinction triggered the collapse of ecosystems and a drastic turnover in mammalian communities leading to the demise of many ecologically specialized species. While Mesozoic mammals were ecomorphologically diverse, recognizable ecological richness was only truly established in the Eocene. Questions remain about the ecology of the first wave of mammals radiating after the extinction. Here, we use the semicircular canals of the inner ear as a proxy for locomotor behavior. Thirty new inner ear virtual endocasts were generated using high-resolution computed tomography scanning. This sample was supplemented by data from the literature to construct a dataset of 79 fossils spanning the Jurassic to the Eocene alongside 262 extant mammals. Vestibular sensitivity was measured using the radius of curvature against body mass and the residuals of this relationship were analyzed. The petrosal lobule size relative to body mass were compared with the inner ear data as they have a role in maintaining gaze stabilization during motion. Paleocene mammals exhibited smaller canal radius of curvature, compared to Mesozoic, Eocene, and extant taxa. In the early Paleocene, canal radius and associated petrosal lobules were relatively smaller on average compared to other temporal groups, suggesting less ability for fast movements.