Some recent academic and popular literature implies that the problem of the colonization of the Americas has been largely resolved in favor of one specific model: a Pacific coastal migration, dependent on high marine productivity, from the Bering Strait to South America, thousands of years before Clovis, the earliest widespread cultural manifestation south of the glacial ice. Speculations on maritime adaptations and typological links (stemmed points) across thousands of kilometers have also been advanced. A review of the current genetic, archeological, and paleoecological evidence indicates that ancestral Native American population expansion occurred after 16,000 years ago, consistent with the archeological record, particularly with the earliest securely dated sites after ~15,000 years ago. These data are largely consistent with either an inland (ice-free corridor) or Pacific coastal routes (or both), but neither can be rejected at present. Systematic archeological and paleoecological investigations, informed by geomorphology, are required to test each hypothesis.
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http://dx.doi.org/10.1126/sciadv.aat5473 | DOI Listing |
Mar Pollut Bull
January 2025
Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, China; Observation and Research Station of Coastal Wetland Ecosystem in Beibu Gulf, Ministry of Natural Resources, Beihai 536015, China. Electronic address:
The temporal variation and transport of Cs in the Beibu Gulf (BG) are still poorly understood. Here we measured Cs concentrations in the BG water column and surface sediments during 2022. We found that Cs in the BG water column was controlled by the movement and mixing of local water masses.
View Article and Find Full Text PDFMar Pollut Bull
January 2025
University of Victoria, 3800 Finnerty Road, Victoria, BC V8W 2Y2, Canada. Electronic address:
Marine pollution poses significant risks to both marine ecosystems and human health, requiring effective monitoring and control measures. This study presents the Ocean Pollution Monitoring System (OPMS), a web application designed to visualize the seasonal and annual fluctuations of marine pollutants along coastal regions in Canada. The pollutants include fecal coliform and biotoxins such as paralytic shellfish poisoning (PSP), and amnesic shellfish poisoning (ASP).
View Article and Find Full Text PDFProtist
December 2024
Department of Aquatic Life Medicine, College of Ocean and Biosciences, Kunsan National University, 558 Daehakro, Gunsan 54150, Republic of Korea; Research Institute of Fisheries Science in Offshore Wind farm (RIFSO), Kunsan National University, 558 Daehakro, Gunsan 54150, Republic of Korea. Electronic address:
This study discovered the first Asian population of Sphaeroforma nootkatensis (SphX), a member of Mesomycetozoea, in the southern coastal region of South Korea. Although investigating parasites in Pacific oysters (Crassostrea gigas), a single-cell microorganism was isolated from gill tissues. Comprehensive phylogenetic analysis of its 18S rDNA revealed its placement within the order Ichthyophonida, class Mesomycetozoea.
View Article and Find Full Text PDFInt J Environ Sci Technol (Tehran)
April 2024
Pacific Ecological Systems Division, Center for Public Health and Environmental Assessment, U.S. Environmental Protection Agency, Corvallis, OR 97333-4902, USA.
Approximately 390,000 abandoned mines across the US pose considerable, pervasive risks to human and environmental health; world-wide the problem is even greater. Lime, organic materials, and other amendments have been used to decrease metal bioavailability (e.g.
View Article and Find Full Text PDFSci Total Environ
December 2024
North Slope Borough, Department of Wildlife Management, Utqiaġvik, AK 99723, USA; Institute of Arctic Biology, University of Alaska, Fairbanks, AK 99708, USA.
Ringed (Pusa hispida), bearded (Erignathus barbatus), spotted (Phoca largha), and ribbon (Histriophoca fasciata) seals are ice-associated seals that are important subsistence resources for coastal Alaska Native people. These seals are also mid- to upper trophic level Arctic predators and primary prey of polar bears (Ursus maritimus). We analyzed concentrations of 19 trace elements in seal liver, kidney, muscle, and blubber, including arsenic, cadmium, lead, mercury, and vanadium due to their potential toxicity.
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