Dairying, diseases and the evolution of lactase persistence in Europe

Update notice Author Correction: Dairying, diseases and the evolution of lactase persistence in Europe (Nature, (2022), 608, 7922, (336-345), 10.1038/s41586-022-05010-7) Nature, Volume 609, Issue 7927, Pages E9, 15 September 2022In European and many African, Middle Eastern and southern Asian populations, lactase persistence (LP) is the most strongly selected monogenic trait to have evolved over the past 10,000 years(1). Although the selection of LP and the consumption of prehistoric milk must be linked, considerable uncertainty remains concerning their spatiotemporal configuration and specific interactions(2,3). Here we provide detailed distributions of milk exploitation across Europe over the past 9,000 years using around 7,000 pottery fat residues from more than 550 archaeological sites. European milk use was widespread from the Neolithic period onwards but varied spatially and temporally in intensity. Notably, LP selection varying with levels of prehistoric milk exploitation is no better at explaining LP allele frequency trajectoriesthan uniform selection since the Neolithic period. In the UK Biobank(4,5) cohort of 500,000 contemporary Europeans, LP genotype was only weakly associated with milk consumption and did not show consistent associations with improved fitness or health indicators. This suggests that other reasons for the beneficial effects of LP should be considered for its rapid frequency increase. We propose that lactase non-persistent individuals consumed milk when it became available but, under conditions of famine and/or increased pathogen exposure, this was disadvantageous, driving LP selection in prehistoric Europe. Comparison of model likelihoods indicates that population fluctuations, settlement density and wild animal exploitation-proxies for these drivers-provide better explanations of LP selection than the extent of milk exploitation. These findings offer new perspectives on prehistoric milk exploitation and LP evolution.Peer reviewe

Sediment Characterization and Beachfill Borrow Area Assessment of the Delaware Bay Study. Report 1, Identification of Sediment Types Offshore of Broadkill Beach, Delaware, Area

Source: https://erdc-library.erdc.dren.mil/jspui/Erosion is occurring along the shoreline of Delaware Bay, comprising the east coast within the state of New Jersey and the west coast within the state of Delaware. This erosion has resulted in a need to investigate the shallow offshore areas of the bay adjacent to both the Delaware and New Jersey coasts for use as borrow areas for beachfill material. The area is relatively unexplored from a geotechnical standpoint and this investigation will provide acoustical subbottom profiling, vibracore locations, and interpretation of the sediment substrate of the study area. Seismic and sedimentological data from vibracore samples were interpreted, and this report characterizes the sediment of the Broadkill Beach portion on the west side of the bay of the Delaware Beach study. This report also suggests suitable borrow areas for beachfill use

Beach Nourishment Project Response and Design Evaluation: Ocean City Maryland. Report 1, 1988-1992

Source: https://erdc-library.erdc.dren.mil/jspui/Detailed monitoring of the performance of a two-phase beach nourishment project has provided valuable information on beach fill behavior and long-term response of a beach fill to prevailing coastal processes. The Atlantic Coast of Maryland (Ocean City) Shoreline Protection Project began with placement of a recreational beach by the State of Maryland during the summer of 1988. Within three months of placement, four storms impacted the area. Recovery was monitored for an additional two years. In the summers of 1990 and 1991, additional fill material including a storm protection dune was placed by the U.S. Army Corps of Engineers as a second phase for the purpose of storm protection. Within a year of the first placement, two large storms impacted the project. Initial recovery was also documented. Project monitoring included 12 profile survey lines, sediment collection, and placement of two dedicated wave gauges. The beach nourishment project performed well in protecting the beachfront infrastructure of Ocean City from storm damage. The fill material was eroded from the foreshore after the major storms of 1989 and 1991/92, but could be accounted for in the nearshore between the shoreline and closure. Representative profile survey locations show the differential behavior of the fill controlled by nearshore bathymetric variability along the project length. The 37th Street location represents the flatter, bar/trough type profile typical of the southern portion of the fill. Localized "hot spots" of erosion occurred in areas where a shoal system attaches to the shoreface, as shown at 81st Street. The erosion pattern associated with these shoals was probably produced by wave convergence and divergence over these features. Analysis of sediment characteristics of samples collected during the State fill project showed the influence of the fill material on the native beach and the change in sorting after the passage of four storms. Composites were constructed of the foreshore and nearshore samples to account for cross-shore variability in grain size distribution. The coarsest foreshore and finest nearshore composite fill material was found in the northern end of the project, with the opposite found to the south. Storm impact placed coarse foreshore lag material at the erosional 81st Street location and finer material at the more stable 37th Street location. After 9 months, the fill material was taking on the characteristics of the pre-fill native beach

SUPERDUCK Beach Sediment Sampling Experiment: Beach Profile Change and Foreshore Sediment Dynamics

Source: https://erdc-library.erdc.dren.mil/jspui/The purpose of the SUPERDUCK Beach Sediment Sample Experiment was to study beach response to storm waves. Data were collected during an 11-day experiment influenced by two extratropical storms. Daily beach profiles were surveyed along four lines to give a three-dimensional picture of beach response. Surface sediment samples were collected at the berm, upper swash, and lower swash to examine daily grain size distribution changes. Wave data collection from a wave gage located in 8 m of water provided changes in wave height and period during the two storms. The foreshore exhibited progressive daily erosion during the first 5 days of the experiment as the first storm event waned. The last 6 days showed a progressive accretion on the foreshore, even under the influence of the second storm. Most variability in daily sediment grain size distribution occurred in the upper swash, a zone of both uprush and backwash influence. Berm samples were finer and better sorted, deposited at the area of maximum uprush. Lower swash samples were coarser and more poorly sorted as the backwash interacted with incoming surf bores. Behavior of the foreshore was partially independent of waves as nearshore bathymetry appeared to play a dominant role in the erosion and accretion pattern