MARMAM subscribers, On behalf of my colleagues from South America, I am pleased to share an open-access paper recently published on a fossil marine mammal site in Atacama Region, Chile. This work will interest anyone working on marine mammal strandings, their taphonomy, and their paleoecology. Also, it was the result of a great collaboration over the course of nearly four years: 14 co-authors, from students to professors to curators, and across museums and universities internationally. We especially thank our Chilean partner institutions at Museo Nacional de Historia Natural, Chile; Consejo de Monumentos Nacionales; and Universidad de Chile. Pyenson ND, Gutstein CS, Parham JF, Le Roux JP, Chavarría CC, Little H, Metallo A, Rossi V, Valenzuela-Toro AM, Velez-Juarbe J, Santelli CM, Rubilar Rogers D, Cozzuol MA, Suárez ME. 2014. Repeated mass strandings of Miocene marine mammals from Atacama Region of Chile point to sudden death at sea. Proc. R. Soc. B. 2014 281 20133316. doi:10.1098/rspb.2013.3316 Available via Open Access at: http://rspb.royalsocietypublishing.org/content/281/1781/20133316.full Abstract: Marine mammal mass strandings have occurred for millions of years, but their origins defy singular explanations. Beyond human causes, mass strandings have been attributed to herding behaviour, large-scale oceanographic fronts and harmful algal blooms (HABs). Because algal toxins cause organ failure in marine mammals, HABs are the most common mass stranding agent with broad geographical and widespread taxonomic impact. Toxin-mediated mortalities in marine food webs have the potential to occur over geological timescales, but direct evidence for their antiquity has been lacking. Here, we describe an unusually dense accumulation of fossil marine vertebrates from Cerro Ballena, a Late Miocene locality in Atacama Region of Chile, preserving over 40 skeletons of rorqual whales, sperm whales, seals, aquatic sloths, walrus-whales and predatory bony fish. Marine mammal skeletons are distributed in four discrete horizons at the site, representing a recurring accumulation mechanism. Taphonomic analysis points to strong spatial focusing with a rapid death mechanism at sea, before being buried on a barrier-protected supratidal flat. In modern settings, HABs are the only known natural cause for such repeated, multispecies accumulations. This proposed agent suggests that upwelling zones elsewhere in the world should preserve fossil marine vertebrate accumulations in similar modes and densities Also, we have built an open-access website where anyone can download or interact with 3D models of the fossil baleen whale skeletons; use GoogleEarth maps of the excavation quarries; look at a vast collection of high-resolution field photos and videos; or take 360 degree tours of the site. Open Access Smithsonian Website: http://cerroballena.si.edu Sincerely, Nicholas D. Pyenson, Ph.D. Curator of Fossil Marine Mammals Department of Paleobiology National Museum of Natural History Smithsonian Institution NHB, MRC 121, PO Box 37012 10th & Constitution NW Washington, DC 20013-7012 USA Tel: 202-633-1366 Fax: 202-786-2832 Email: PyensonN@si.edu Twitter: @PyensonLab Lab blog: http://nmnh.typepad.com/pyenson_lab/ Staff page: http://paleobiology.si.edu/staff/individuals/pyenson.cfm