Four pollen diagrams from Minorca (Balearic Islands) have been correlated with other previously studied sequences from Majorca and Minorca to define a Holocene landscape sequence for the region from 8000 yr B.P. to the present. The lower part of the pollen diagrams reflects a climatic phase with more rain and less-marked seasonality than today. Significant quantities of Corylus, Buxus, and mesophilous taxa are found. In the middle part, between 5000 and 4000 yr B.P., a strong change is recorded in composition and structure of the vegetational landscape, with vegetation appearing that was adapted to Mediterranean conditions. This episode coincided with the first human colonization of the island and also with a widespread climatic change in the western Mediterranean region. The change in taxa was complex and some sclerophyllous taxa such Olea played an important role in the transformation of the landscape physiognomy from the mid-Holocene until the present. Although human activities have removed much of the Mediterranean vegetation on the Balearic Islands, it seems clear that the changes have been brought about, in part, by increasing dryness.

Last-glacial paleoenvironments have been reconstructed from a pollen and charcoal record analyzed in organic sediments and dated between ca. 18,000 and >48,00014C yr B.P. The site is located near the village Catas Altas in the lower highland region of southeastern Brazil. The last-glacial landscape was covered by extensive areas of subtropical grasslands and small areas of gallery forests along the rivers, where tropical semideciduous forests and cerrado ecosystems exist today. The subtropical gallery forests were composed ofAraucariaforest trees such asAraucaria angustifolia, Podocarpus, Drimys, Ilex,andSymplocos.Paleofires were frequent. The record indicates that subtropical grassland vegetation, which today is found in patches on the highlands in southern Brazil (especially in the state of Santa Catarina), expanded from southern Brazil to southeastern Brazil, over a distance of more than 750 km, from latitudes of about 28° S to at least 20° S. The completely different last-glacial environment, in comparison to the present-day environment, reflects a dry and cold climate with strong frosts during the winter months. Temperatures of 5°–7°C below those of the present are inferred for the last glaciation.

Nerja Cave is a karstic cavity used by humans from Late Paleolithic to post-Chalcolithic times. Remains of molluscan foods in the uppermost Pleistocene and Holocene sediments were studied with cluster analysis and principal components analysis, in bothQ and R modes. The results from cluster analysis distinguished interval groups mainly in accordance with chronology and distinguished assemblages of species mainly according to habitat. Significant changes in the shellfish diet through time were revealed. In the Late Magdalenian, most molluscs consumed consisted of pulmonate gastropods and species from sandy sea bottoms. The Epipaleolithic diet was more varied and included species from rocky shorelines. From the Neolithic onward most molluscs consumed were from rocky shorelines. From the principal components analysis inQ mode, the first factor reflected mainly changes in the predominant capture environment, probably because of major paleogeographic changes. The second factor may reflect selective capture along rocky coastlines during certain times. The third factor correlated well with the sea-surface temperature curve in the western Mediterranean (Alboran Sea) during the late Quaternary.

Geologic evidence suggests that great (magnitude 8 or larger) earthquakes, or series of such earthquakes, occurred six times in the past 3000 yr at the northern Cascadia subduction zone. The archaeological record, and native oral traditions, demonstrate that native villages along the adjacent coasts of southern British Columbia and Washington State were occasionally abandoned in the late Holocene as a result of these earthquakes and associated tsunamis. We infer the temporal pattern of village occupation and abandonment from midden stratigraphy and from an activity index based on the probability distributions of radiocarbon ages at 30 archaeological sites in three regions of northern Cascadia. Deposits of probable tsunami origin are interbedded with, or bound, cultural strata at several sites. Earthquakes probably predate hiatuses in occupation, or periods of low inferred human activity, at many sites. The strongest correlation between earthquake incidence and site abandonment occurs in the Nootka Sound region. Effects of tsunamis vary with village location, coastal morphology, and late Holocene sea-level history.

Hominids left Africa and occupied mainland Asia by 1.8 myr ago. About 1.15 myr ago Homo erectus and an associatedStegodon–Ailuropoda fauna migrated from subtropical China across the Qinling Mountains into the temperate Loess Plateau. This migration may be an evolutionary milestone in human adaptability because it may represent the first occupation of a nontropical environment. Loess–paleosol stable isotope ratios from the last interglacial–glacial cycle provide comparative data for reconstructing the hominid paleoenvironments. The climate during Gongwangling hominid occupation about 1.15 myr ago was influenced by both Siberian–Mongolian winter and Indian summer monsoon systems characterized as a cold/cool, dry winter and warm/mild, semihumid summer and fall. The Gongwangling hominids preyed mainly on warm-climate-adapted animals such asStegodon–Ailuropoda fauna, suggesting a warm season occupation. The stable isotope ratios also indicate that the Chenjiawo hominids occupied an environment similar to that of the Gongwangling about 650,000 yr ago. The associated fauna, with a mixture of forest and steppe, warm- and cold/cool-climate-adapted animal assemblage's, suggests a permanent occupation by this time. Thus, the reliable earliest and permanent occupation of temperate environments may have occurred 150,000 yr earlier in eastern Asia rather than in Europe.

Palynological study of two subalpine ponds on the Queen Charlotte Islands reveals changes in tree line and climate during the Holocene. The findings agree with previous reconstructions, from nearby Louise Pond on the Queen Charlotte Islands, that suggest a warmer-than-present climate and higher-than-present tree lines in the early Holocene (ca. 9600–6600 14C yr B.P.). Basal ages at SC1 Pond and Shangri-La Bog indicate that the basins did not hold permanent water before 7200 14C yr B.P., consistent with a warmer and drier early Holocene previously inferred from Louise Pond. Pollen and plant macrofossils indicate the initial establishment of subalpine conditions by 6090 ± 90 14C yr B.P., similar to the 5790 ± 130 14C yr B.P. age for cooling inferred from Louise Pond. Conditions similar to present were established at SC1 Pond by 3460 ± 100 14C yr B.P., confirming the previous estimate of 3400 14C yr B.P. at Louise Pond. This 3400 14C yr B.P. vegetation shift on the Queen Charlotte Islands corresponds with the beginning of the Tiedemann glacial advance in the south-coastal mountains of British Columbia (ca. 3300 14C yr B.P.), the Peyto and Robson glacial advances between 3300 and 2800 14C yr B.P. in the Rocky Mountains, and climatic cooling inferred from palynological studies throughout southern British Columbia, northern Washington, and southeast Alaska. These findings confirm that changes in regional climate influenced changes in vegetation in coastal British Columbia.

Seismic stratigraphy, sedimentary facies, pollen stratigraphy, diatom-inferred salinity, stable isotope (δ18O and δ13C), and chemical composition (Sr/Ca and Mg/Ca) of authigenic carbonates from Moon Lake cores provide a congruent Holocene record of effective moisture for the eastern Northern Great Plains. Between 11,700 and 950014C yr B.P., the climate was cool and moist. A gradual decrease in effective moisture occurred between 9500 and 710014C yr B.P. A change at about 710014C yr B.P. inaugurated the most arid period during the Holocene. Between 7100 and 400014C yr B.P., three arid phases occurred at 6600–620014C yr B.P., 5400–520014C yr B.P., and 4800–460014C yr B.P. Effective moisture generally increased after 400014C yr B.P., but periods of low effective moisture occurred between 2900–280014C yr B.P. and 1200–80014C yr B.P. The data also suggest high climatic variability during the last few centuries. Despite the overall congruence, the biological (diatom), sedimentological, isotopic, and chemical proxies were occassionally out of phase. At these times the evaporative process was not the only control of lake-water chemical and isotopic composition.

Twenty archaeological campsites intercalated between more than 30 debris flows caused by heavy rainfall events between 6200 and 3100 14C yr B.P. have recently been discovered at Quebrada Puripica in the Atacama Desert of northern Chile. This record provides detailed information about extreme, short-lived climatic events during the hyperarid mid-Holocene period. For the first time, we found evidence of continuous human occupation in this area, filling the regional hiatus in the Atacama basin (“Silencio Arqueologico”) between 8000 and 4800 14C yr B.P. The transformation of Early Archaic hunters into the complex Late Archaic cultural tradition was an adaptive process. During this time, the site was a local ecological refuge with abundant resources in a generally hostile environment.

An isotopic investigation of upper Pleistocene mammal bones and teeth from Scladina cave (Sclayn, Belgium) demonstrated the very good quality of collagen preservation. A preliminary screening of the samples used the amount of nitrogen in whole bone and dentine in order to estimate the preserved amount of collagen before starting the extraction process. The isotopic abundances of fossil specimens from still-extant species are consistent with their trophic position. Moreover, the15N isotopic abundance is higher in dentine than in bone in bears and hyenas, a phenomenon already observed in modern specimens. These results demonstrate that the isotopic compositions of samples from Scladina cave can be interpreted in ecological terms. Mammoths exhibit a high15N isotopic abundance relative to other herbivores, as was the case in Siberian and Alaskan samples. These results suggest distinctive dietary adaptations in herbivores living in the mammoth steppe. Cave bears are clearly isotopically different from coeval brown bears, suggesting an ecological separation between species, with a pure vegetarian diet for cave bear and an omnivorous diet for brown bear.

Holocene deposits of Mahoney Lake, a meromictic saline lake located in a closed basin in the semi-arid Okanagan Valley, contain evidence of frequent and marked changes in lake depth (up to >12 m/10014C yr) probably caused by short-term changes in effective precipitation. We studied a 5.45-m-long core comprising a basal layer of inorganic mud overlain by a succession of layers of calcareous laminated and nonlaminated organic mud, marl, and sand. We used Mazama tephra to adjust nine radiocarbon ages for the hardwater effect. Meromixis developed ca. 900014C yr B.P., and the lake has been episodically meromictic for about half the time since. Because of close linkages between sediments and depositional environments in meromictic and saline lakes, we infer that laminated sediments indicate meromictic conditions and high lake levels (>ca. 12 m water depth), whereas thick marl layers and nonlaminated sediments indicate nonmeromictic conditions and thus low lake levels (<ca. 8 m depth). Many of the inferred short-term climatic changes have not been identified in previous studies in northwestern North America, perhaps because of insensitive climatic proxies, inadequate temporal resolution, or discounting of anomalous findings.

The Holocene expansion of eastern larch (Larix laricina[Du Roi] K. Koch) at the edge of its geographical range in northwestern Québec was reconstructed using pollen and macrofossils from peat deposits. BecauseLarixis a poor pollen producer, the total pollen sum of 300–500 grains per spectrum was supplied by an additional survey of 2000 grains. However, the use of 2000 pollen counts did not give a betterLarixrecord. The combination of both pollen and macrofossil analyses offered greater opportunities to estimate the time of arrival of eastern larch at the edge of its distributional range. Along the study transect, eastern larch established east of 75° W long before 2000 yr B.P. but not sooner than 5000 yr B.P., whereas it arrived much later, after 1500 yr B.P., in most sites west of 75° W within a migration corridor around 57° 45′ N. The macrofossil record is completely different between the eastern sites, with high frequencies and densities, and the western sites where larch occurs sporadically with few remains only, concentrated in the upper part of the peat profiles. The colonization pattern of eastern larch was patchy in time and space, as suggested by the available macrofossil records, present distributional pattern in the area, and age structure of extant populations. The establishment of disjunct larch populations in the westernmost sites most likely proceeded from long-distance transport. The spatial–temporal pattern of eastern larch west of 74° W may have been influenced by the site conditions associated with late deglaciation in central northern Québec.

Seventy well-preserved fossil remains from deposits of an eroded karstic cave in the Upper Galilee of northern Israel includeUrsus deningeri(Ursidae),Canis lupus cf.mosbachensis (Canidae),Crocuta crocuta cf. praespelaea (Hyaenidae), Panthera leo cf. spelaea (Felidae), and Dama sp. (Cervidae). This assemblage probably dates to the Early Toringian (MQ2, Middle Pleistocene). Ursus deningeri and Panthera leo cf. spelaeahave never before been recorded south of the Taurus–Zagros mountain chain. We correlate the carnivore faunule with some Near Eastern and southern Levantine sites and assume that only a severe cold phase could have shifted these species over the Taurus–Zagros mountain chain this far to the south. Due to the relative scarcity of Middle Pleistocene assemblages, especially carnivores, in the southern Levant, the biogeographic connection between the southern Levant and the Near East is still not well known. This faunule elucidates Pleistocene biotic exchanges between Europe and the Levant during this period.

Strandplains of shore-parallel beach ridges bordering the Great Lakes are valuable for reconstructing histories of climate-related lake-level fluctuations. However, imprecise radiocarbon dates of ridge formation have frustrated development of dependable chronologies from which information about variation in the frequency of ridge formation and inferred climate fluctuations can be obtained. The resolution and precision of radiocarbon chronologies can be improved with AMS 14C dates of roots and rhizomes of plant species associated with the formation and growth of the sand-dune caps of breach ridges. These dates reliably estimate the timing of shore progradation when the base of the previously established beach ridge becomes inundated by the water table. An AMS radiocarbon chronology of beach-ridge formation in northern Lake Michigan shows that information about variation in the frequency of ridge formation is important for paleoclimatic interpretation.