Teeth of northern bog lemming, Mictomys borealis, are reported from Cathedral and Smith Creek caves and represent the first Wisconsin remains of the genus from the Great Basin. Specimens from Cathedral Cave, Snake Range, are associated with U-series ages of 24,000 to 15,000 yr B.P. Previous work with pollen and packrat middens, dating to the same age as the Mictomys, indicate that Smith Creek Canyon contained a riparian, locally mesic community, including Picea engelmannii (spruce), Betula sp. (birch), Cercocarpus sp. (mountain mahogany), and Artemisia sp. (sagebrush) among other species. Exposed canyon slopes and the adjacent valley apparently contained a more xeric steppe community including sagebrush and Chenopodiineae species; rocky outcrop permitted Pinus flexilis (limber pine) and P. longaeva (bristlecone pine) to grow adjacent to Lake Bonneville or low in the canyon. The region apparently experienced a dry climate (not necessarily drier than today); however, Smith Creek Canyon was fed by glacial meltwater from Mt. Moriah. The northern bog lemming probably lived only in the riparian community and possibly on the north-facing slope below Cathedral Cave. Few canyons of the Snake Range would have had the unusually mesic conditions found in Smith Creek Canyon.

A transfer function has been established to quantify the dissolution of diatom silica in Southern Ocean sediments. The relationship between the amount of silica dissolution and changes in diatom species distribution is built by controlled progressive dissolution of biogenic silica in five recent sediment samples from box-core tops, each representative of a modern diatom species sediment assemblage. The amount of dissolved silica was measured for each experiment. The resulting data set of species abundances (42 samples containing 32 diatom species and 2 silicoflagellate genera) was added to the modern data base of diatom species distributed over the Southern Ocean (124 core tops). Q-mode factor analysis individualizes four factors explaining 83% of the variance. The first three factors are controlled by surface water properties (mostly temperature). The fourth factor is the only one correlated with loss of silica in the reference samples (R = 0.900). We quantified the dissolution factor using this correlation: superficial sediments of the Southeast Indian Ocean are characterized, from low to high latitudes, by a decrease in silica loss by dissolution (from >50 to 10%) from the Subantarctic Zone (40°S) to around 55°S, followed by an increase of silica loss to values larger than 60% between 63° and 68°S. Application of the dissolution factor in two cores from the Southern Ocean (≈44° and 55°S) shows enhanced opal dissolution during the last glaciation, particularly during Emiliani's stage 3 (from 40,000 to 30,000 yr B.P.).

Late Quaternary paleoenvironmental data for East Africa are derived primarily from montane sources and thus we know little about the changing composition of East African savannas. Four archaeological sites at Lukenya Hill in the savanna of the Athi-Kapiti Plains of Kenya that date to the last 40,000 yr preserve a large mammalian fauna. The prehistoric hunters concentrated on migratory ungulates and virtually ignored the resident inselberg ungulates throughout the occupation. Faunas of the last glacial maximum are dominated by an extinct small alcelaphine antelope. Arid-adapted ungulates are present that are regionally absent historically, and Pelorovis is present as well. The small alcelaphine and arid-adapted ungulates are absent in the Holocene deposits. This suggests that there was an expansion of dry savannas during the last glacial maximum. The last glacial maximum aridity, combined with a lack of pastoral-set fires, would have resulted in a vegetative mosaic distinct from the present. Dry woody growth and dry and/or tall grass, all of which are poor forage for ungulates, would have been common where seasonally moist short grasslands are presently extant. These conditions favored the large-bodied, highly hypsodont species in Africa that became extinct with the onset of wet conditions during the early Holocene.

Cold-adapted beetles colonized the lowlands of the Lake Region of south-central Chile following the retreat of glaciers from their maximum extent at about 19,500 yr B.P. The beetle fauna from 18,000 to 14,000 yr B.P. was characterized by species of moorland habitats. This fauna was species-poor compared to later faunas of the postglacial interval. By 14,000 yr B.P. arboreal species were replacing species of open habitats, reflecting a change toward a warmer climate. By about 12,500 yr B.P. fossil beetle assemblages consisted entirely of rain forest species. The fauna of the postglacial interval was about five times as species-rich as that of the glacial interval. The change in species composition and greater diversity of the beetle fauna was produced by an increase in mean annual temperature estimated to be about 4°–5°C. This was the last major climatic change to affect profoundly the biota of the middle latitudes of South America. The fossil beetle assemblages do not imply a reversal to a colder climate at the time of the European Younger Dryas interval between 11,000 and 10,000 yr B.P.

The composite frequency of radiocarbon ages for Holocene marine fossils from beaches around Antarctica is significantly different than random. Variations in the frequency of fossil ages coincide with the timing of Holocene climate changes inferred from Antarctic ice cores, sub-Antarctic lakes, polar and alpine moraines, and sea level. Extant Antarctic marine species that occur as fossils in beaches may reflect coastal meltwater impacts associated with ice sheet marginal fluctuations that were circumpolar during the Holocene.

Effective hydration temperature (EHT) is essential for the computation of obsidian hydration dates. In the Atacama Desert, the scarcity of air-temperature records combines with extremes of elevation and local temperature to encourage, or even require, the use of buried thermal cells to record on-site mean annual temperatures. Compositional analysis (sourcing) and hydration rate development in the laboratory are also necessary, especially where other dating methods are unavailable to confirm the hydration rate. Paleoindian or Early Archaic through modern obsidian dates support a human settlement pattern history derived from archaeological/geomorphological studies of climatological and hydrological change.

Four pollen sequences along a transect from north-central Iowa to southeast Wisconsin reveal the distribution of prairie and forest during the Holocene and test the use of pollen isopolls in locating the Holocene prairie-forest border. Prairie was dominant in central Iowa and climate was drier than present from about 8000 to 3000 yr B.P. During the driest part of this period in central Iowa (6500-5500 yr B.P.), mesic forest prevailed in eastern Iowa and Wisconsin, suggesting conditions wetter than at present. Prairie replaced the mesic forest about 5400 yr B.P. in eastern Iowa but did not extend much farther east; mesic forests were replaced in southern Wisconsin and northern Illinois about 5400 yr B.P. by xeric oak forests. This change from mesic to xeric conditions at 5400 yr B.P. was widespread and suggests that the intrusion of drier Pacific air was blocked by maritime tropical air from the Gulf of Mexico until the late Holocene in this area.

TL dating of both quartz and potassium feldspar grains from the Pleistocene beach of Sangatte, at the southern limit of the North Sea Basin, give self-consistent ages of 200,000 ± 45,000, 205,000 ± 14,000, and 229,000 ± 18,000 years, respectively. These results allow the beach deposits to be correlated with oxygen isotope stage 7 (244,000–190,000 yr) (Martinson et al., 1987). The existence of a fossil beach cliff line at 10 m above French O.D. demonstrates that the Strait of Dover was open during the penultimate interglaciation.