Radiocarbon‐dated fossils indicate woolly mammoths were extirpated from mainland Beringia around 13 000 years ago. However, environmental DNA in permafrost suggests small “cryptic“ populations survived into the Holocene. Resolving this discrepancy is crucial to understanding the drivers of mammoth extinction. The Adopt‐a‐Mammoth project, launched in 2022, is increasing the number of radiocarbon‐dated mammoth fossils to locate...

A submillennial‐resolution record of lake water oxygen isotope composition (δ 18 O) from chironomid head capsules is presented from Burial Lake, northwest Alaska. The record spans the Last Glacial Maximum (LGM; ~20–16k cal a bp ) to the present and shows a series of large lake δ 18 O shifts (~5‰). Relatively low δ 18 O values occurred during a period covering the LGM, when the lake was a shallow, closed‐basin pond. Higher valu...

The Bering Land Bridge (BLB) last connected Eurasia and North America during the Late Pleistocene. Although the BLB would have enabled transfers of terrestrial biota in both directions, it also acted as an ecological filter whose permeability varied considerably over time. Here we explore the possible impacts of this ecological corridor on genetic diversity within, and connectivity among, populations of a once wide‐ranging gro...

Numerous paleoecological questions concern the mobility of ancient fauna in eastern Beringia. Strontium (Sr) isotope ratio ( 87 Sr/ 86 Sr) analysis has emerged as a powerful tracer for determining the provenance of ancient biological materials. However, it is important to characterize 87 Sr/ 86 Sr variation across a landscape. We measured the 87 Sr/ 86 Sr composition of teeth from present‐day, herbivorous rodents ( n = 162) sa...

Existing paleoclimate data are exceedingly sparse from southern Spitsbergen, a High Arctic region predicted to experience significant environmental changes because of amplified warming. We analyzed biotic and isotopic paleolimnological proxies to reconstruct past climate from a lacustrine sediment core, with a basal age of ∼5500 a BP , in southern Spitsbergen (77°N). We used fossil Chironomidae assemblages to quantitatively re...

Aim The Bering Land Bridge ( BLB ) connected Asia and North America during glacial periods, supported a diverse ecosystem of now‐vanished megafauna, and is a proposed glacial refugium. This study tests whether southern coastal Beringia was a refugium for woody taxa during the Last Glacial Maximum ( LGM ) and hypotheses about habitats available on the BLB before and after megafaunal extinction. Location St. Paul Island, Alaska....

Summary Aerobic methane ( CH 4 ) oxidation mitigates CH 4 release and is a significant pathway for carbon and energy flow into aquatic food webs. Arctic lakes are responsible for an increasing proportion of global CH 4 emissions, but CH 4 assimilation into the aquatic food web in arctic lakes is poorly understood. Using stable isotope probing ( SIP ) based on phospholipid fatty acids ( PLFA‐SIP ) and DNA ( DNA‐SIP ), we tracke...

Pollen, charcoal, stable carbon and nitrogen isotope, and radiocarbon analyses are used to reconstruct a palaeoenvironmental record from the Eastern Arc Mountains (EAM), Tanzania, dating back >45 000 years. A sedimentary hiatus covering the last glacial‐interglacial transition (LGIT) and early to mid Holocene follows the lead up to the Last Glacial Maximum (LGM) period. A late Holocene portion of the record is included as a mo...

Summary Arctic lakes are a significant source of the greenhouse gas methane (CH 4 ), but the role that methane oxidizing bacteria (methanotrophs) play in limiting the overall CH 4 flux is poorly understood. Here, we used stable isotope probing (SIP) techniques to identify the metabolically active aerobic methanotrophs in upper sediments (0–1 cm) from an arctic lake in northern Alaska sampled during ice‐free summer conditions....

We present a multi‐proxy reconstruction from a well‐preserved vegetation surface (ca. 32 000 14 C a BP) from the Fox Permafrost tunnel near Fairbanks, Alaska. A thick litter layer of plant material on the vegetation surface is consistent with the vegetation lacking evidence of disturbance. Plant macrofossils and graminoid cuticle analysis show the presence of a graminoid assemblage consistent with phytolith data. The pollen da...

Silicon is an essential nutrient for marine diatoms, which dominate the export of organic carbon to the deep ocean. Despite the dominance of the oceanic Si budget by fluvial inputs and the role of the land biosphere in controlling Si losses from rocks and soils to rivers, few studies have considered how continental bio geochemical Si fluxes varied on an orbital timescale. We reconstruct changes in Si cycling by the catchment‐l...

Existing at the transition between the terrestrial environment and hydrosphere, mangroves are sensitive to environmental change (e.g. sea‐level rise). We present pollen and stable isotope data from a core (TCC1) of continuous (10 m) mangrove peat from Twin Cays, ∼12 km off of the coast of Belize, Central America. Radiocarbon dates on fragments of mangrove leaves preserved in TCC1 show that the core provides an 8600 14 C year r...