A female woolly mammoth's lifetime movements end in an ancient Alaskan hunter-gatherer camp.

Woolly mammoths in mainland Alaska overlapped with the region's first people for at least a millennium. However, it is unclear how mammoths used the space shared with people. Here, we use detailed isotopic analyses of a female mammoth tusk found in a 14,000-year-old archaeological site to show that she moved ~1000 kilometers from northwestern Canada to inhabit an area with the highest density of early archaeological sites in interior Alaska until her death. DNA from the tusk and other local contemporaneous archaeological mammoth remains revealed that multiple mammoth herds congregated in this region. Early Alaskans seem to have structured their settlements partly based on mammoth prevalence and made use of mammoths for raw materials and likely food.

Sources of primary production to Arctic bivalves identified using amino acid stable carbon isotope fingerprinting.

Benthic invertebrates are a crucial trophic link in Arctic marine food webs. However, estimates of the contribution of different primary production sources sustaining these organisms are not well characterised. We measured the stable carbon isotope values (δ13C) of essential amino acids (EAAs) in muscle tissue from two common bivalve genera (Macoma spp. and Astarte spp.) collected in Hanna Shoal in the northeastern Chukchi Sea. Mixing models comparing the δ13CEAA fingerprints of the bivalves to a suite of primary production endmembers revealed relatively high contributions of EAAs from phytoplankton and bacteria in both species. We also examined whether δ13CEAA fingerprints could be produced from the EAAs preserved in bivalve shells, which could allow primary production sources to be estimated from ancient bivalve shells. The δ13CEAA fingerprints from a suite of paired modern bivalve shells and muscle from Macoma calcarea from across the Chukchi Sea revealed a correspondence between the estimates of the dominant primary production source of EAAs derived from analyses of these two tissue types. Our findings indicate that δ13CEAA fingerprinting of marine bivalves can be used to examine dominant organic matter sources in the Arctic marine benthos in recent years as well as in deeper time.