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The covariation of carbon dioxide (CO2) concentration and temperature in Antarctic ice-core records suggests a close link between CO2 and climate during the Pleistocene ice ages. The role and relative importance of CO2 in producing these climate changes remains unclear, however, in part because the ice-core deuterium record reflects local rather than global temperature. Here we construct a record of global surface temperature from 80 proxy records and show that temperature is correlated with and generally lags CO2 during the last (that is, the most recent) deglaciation. Differences between the respective temperature changes of the Northern Hemisphere and Southern Hemisphere parallel variations in the strength of the Atlantic meridional overturning circulation recorded in marine sediments. These observations, together with transient global climate model simulations, support the conclusion that an antiphased hemispheric temperature response to ocean circulation changes superimposed on globally in-phase warming driven by increasing CO2 concentrations is an explanation for much of the temperature change at the end of the most recent ice age. [ABSTRACT FROM AUTHOR]

Contentious observations of Pleistocene shoreline features on the tectonically stable islands of Bermuda and the Bahamas have suggested that sea level about 400,000 years ago was more than 20 metres higher than it is today. Geochronologic and geomorphic evidence indicates that these features formed during interglacial marine isotope stage (MIS) 11, an unusually long interval of warmth during the ice age. Previous work has advanced two divergent hypotheses for these shoreline features: first, significant melting of the East Antarctic Ice Sheet, in addition to the collapse of the West Antarctic Ice Sheet and the Greenland Ice Sheet; or second, emplacement by a mega-tsunami during MIS 11 (ref. 4, 5). Here we show that the elevations of these features are corrected downwards by ?10 metres when we account for post-glacial crustal subsidence of these sites over the course of the anomalously long interglacial. On the basis of this correction, we estimate that eustatic sea level rose to ?6-13?m above the present-day value in the second half of MIS 11. This suggests that both the Greenland Ice Sheet and the West Antarctic Ice Sheet collapsed during the protracted warm period while changes in the volume of the East Antarctic Ice Sheet were relatively minor, thereby resolving the long-standing controversy over the stability of the East Antarctic Ice Sheet during MIS 11. [ABSTRACT FROM AUTHOR]

Global climate and the atmospheric partial pressure of carbon dioxide () are correlated over recent glacial cycles, with lower during ice ages, but the causes of the changes are unknown. The modern Southern Ocean releases deeply sequestered CO2 to the atmosphere. Growing evidence suggests that the Southern Ocean CO2 ‘leak’ was stemmed during ice ages, increasing ocean CO2 storage. Such a change would also have made the global ocean more alkaline, driving additional ocean CO2 uptake. This explanation for lower ice-age , if correct, has much to teach us about the controls on current ocean processes. [ABSTRACT FROM AUTHOR]

Communities have been shaped in numerous ways by past climatic change; this process continues today. At the end of the Pleistocene epoch about 11,700 years ago, North American communities were substantially altered by the interplay of two events. The climate shifted from the cold, arid Last Glacial Maximum to the warm, mesic Holocene interglacial, causing many mammal species to shift their geographic distributions substantially. Populations were further stressed as humans arrived on the continent. The resulting megafaunal extinction event, in which 70 of the roughly 220 largest mammals in North America (32%) became extinct, has received much attention. However, responses of small mammals to events at the end of the Pleistocene have been much less studied, despite the sensitivity of these animals to current and future environmental change. Here we examine community changes in small mammals in northern California during the last ‘natural’ global warming event at the Pleistocene–Holocene transition and show that even though no small mammals in the local community became extinct, species losses and gains, combined with changes in abundance, caused declines in both the evenness and richness of communities. Modern mammalian communities are thus depauperate not only as a result of megafaunal extinctions at the end of the Pleistocene but also because of diversity loss among small mammals. Our results suggest that across future landscapes there will be some unanticipated effects of global change on diversity: restructuring of small mammal communities, significant loss of richness, and perhaps the rising dominance of native ‘weedy’ species. [ABSTRACT FROM AUTHOR]

Stone tools are durable reminders of the activities, skills and customs of early humans, and have distinctive morphologies that reflect the development of technological skills during the Pleistocene epoch. In Africa, large cutting tools (hand-axes and bifacial chopping tools) became part of Palaeolithic technology during the Early Pleistocene (∼1.5 Myr ago). However, in Europe this change had not been documented until the Middle Pleistocene (<0.5 Myr ago). Here we report dates for two western Mediterranean hand-axe sites that are nearly twice the age of the supposed earliest Acheulian in western Europe. Palaeomagnetic analysis of these two sites in southeastern Spain found reverse polarity magnetozones, showing that hand-axes were already in Europe as early as 0.9 Myr ago. This expanded antiquity for European hand-axe culture supports a wide geographic distribution of Palaeolithic bifacial technology outside of Africa during the Early Pleistocene. [ABSTRACT FROM AUTHOR]

Dust can affect the radiative balance of the atmosphere by absorbing or reflecting incoming solar radiation; it can also be a source of micronutrients, such as iron, to the ocean. It has been suggested that production, transport and deposition of dust is influenced by climatic changes on glacial-interglacial timescales. Here we present a high-resolution record of aeolian dust from the EPICA Dome C ice core in East Antarctica, which provides an undisturbed climate sequence over the past eight climatic cycles. We find that there is a significant correlation between dust flux and temperature records during glacial periods that is absent during interglacial periods. Our data suggest that dust flux is increasingly correlated with Antarctic temperature as the climate becomes colder. We interpret this as progressive coupling of the climates of Antarctic and lower latitudes. Limited changes in glacial-interglacial atmospheric transport time suggest that the sources and lifetime of dust are the main factors controlling the high glacial dust input. We propose that the observed ∼25-fold increase in glacial dust flux over all eight glacial periods can be attributed to a strengthening of South American dust sources, together with a longer lifetime for atmospheric dust particles in the upper troposphere resulting from a reduced hydrological cycle during the ice ages. [ABSTRACT FROM AUTHOR]

The earliest hominin occupation of Europe is one of the most debated topics in palaeoanthropology. However, the purportedly oldest of the Early Pleistocene sites in Eurasia lack precise age control and contain stone tools rather than human fossil remains. Here we report the discovery of a human mandible associated with an assemblage of Mode 1 lithic tools and faunal remains bearing traces of hominin processing, in stratigraphic level TE9 at the site of the Sima del Elefante, Atapuerca, Spain. Level TE9 has been dated to the Early Pleistocene (approximately 1.2–1.1 Myr), based on a combination of palaeomagnetism, cosmogenic nuclides and biostratigraphy. The Sima del Elefante site thus emerges as the oldest, most accurately dated record of human occupation in Europe, to our knowledge. The study of the human mandible suggests that the first settlement of Western Europe could be related to an early demographic expansion out of Africa. The new evidence, with previous findings in other Atapuerca sites (level TD6 from Gran Dolina), also suggests that a speciation event occurred in this extreme area of the Eurasian continent during the Early Pleistocene, initiating the hominin lineage represented by the TE9 and TD6 hominins. [ABSTRACT FROM AUTHOR]

The Yellowstone caldera, in the western United States, formed ∼640,000 years ago when an explosive eruption ejected ∼1,000 km3 of material. It is the youngest of a series of large calderas that formed during sequential cataclysmic eruptions that began ∼16 million years ago in eastern Oregon and northern Nevada. The Yellowstone caldera was largely buried by rhyolite lava flows during eruptions that occurred from ∼150,000 to ∼70,000 years ago. Since the last eruption, Yellowstone has remained restless, with high seismicity, continuing uplift/subsidence episodes with movements of ∼70 cm historically to several metres since the Pleistocene epoch, and intense hydrothermal activity. Here we present observations of a new mode of surface deformation in Yellowstone, based on radar interferometry observations from the European Space Agency ERS-2 satellite. We infer that the observed pattern of uplift and subsidence results from variations in the movement of molten basalt into and out of the Yellowstone volcanic system. [ABSTRACT FROM AUTHOR]

Homo floresiensis was recovered from Late Pleistocene deposits on the island of Flores in eastern Indonesia, but has the stature, limb proportions and endocranial volume of African Pliocene Australopithecus. The holotype of the species (LB1), excavated in 2003 from Liang Bua, consisted of a partial skeleton minus the arms. Here we describe additional H. floresiensis remains excavated from the cave in 2004. These include arm bones belonging to the holotype skeleton, a second adult mandible, and postcranial material from other individuals. We can now reconstruct the body proportions of H. floresiensis with some certainty. The finds further demonstrate that LB1 is not just an aberrant or pathological individual, but is representative of a long-term population that was present during the interval 95–74 to 12 thousand years ago. The excavation also yielded more evidence for the depositional history of the cave and for the behavioural capabilities of H. floresiensis, including the butchery of Stegodon and use of fire. [ABSTRACT FROM AUTHOR]

Massive iceberg discharges from the Northern Hemisphere ice sheets,‘Heinrich events’, coincided with the coldest periods of the last ice age. There is widespread evidence for Heinrich events and their profound impact on the climate and circulation of the North Atlantic Ocean, but their influence beyond that region remains uncertain. Here we use a combination of molecular fingerprints of algal productivity and radioisotope tracers of sedimentation to document eight periods of increased productivity in the subpolar Southern Ocean during the past 70,000 years that occurred within 1,000-2,000 years of a Northern Hemisphere Heinrich event. We discuss possible causes for such a link, including increased supply of iron from upwelling and increased stratification during the growing season, which imply an alteration of the global ocean circulation during Heinrich events. The mechanisms linking North Atlantic iceberg discharges with subantarctic productivity remain unclear at this point. We suggest that understanding how the Southern Ocean was altered during these extreme climate perturbations is critical to understanding the role of the ocean in climate change. [ABSTRACT FROM AUTHOR]

The 100,000-year timescale in the glacial/interglacial cycles of the late Pleistocene epoch (the past~700,000 years) is commonly attributed to control by variations in the Earth's orbit. This hypothesis has inspired models that depend on the Earth's obliquity (~40,000?yr;~40?kyr), orbital eccentricity (~100?kyr) and precessional (~20?kyr) fluctuations, with the emphasis usually on eccentricity and precessional forcing. According to a contrasting hypothesis, the glacial cycles arise primarily because of random internal climate variability. Taking these two perspectives together, there are currently more than thirty different models of the seven late-Pleistocene glacial cycles. Here we present a statistical test of the orbital forcing hypothesis, focusing on the rapid deglaciation events known as terminations. According to our analysis, the null hypothesis that glacial terminations are independent of obliquity can be rejected at the 5% significance level, whereas the corresponding null hypotheses for eccentricity and precession cannot be rejected. The simplest inference consistent with the test results is that the ice sheets terminated every second or third obliquity cycle at times of high obliquity, similar to the original proposal by Milankovitch. We also present simple stochastic and deterministic models that describe the timing of the late-Pleistocene glacial terminations purely in terms of obliquity forcing. [ABSTRACT FROM AUTHOR]

Currently, it is widely accepted that only one hominin genus, Homo, was present in Pleistocene Asia, represented by two species, Homo erectus and Homo sapiens. Both species are characterized by greater brain size, increased body height and smaller teeth relative to Pliocene Australopithecus in Africa. Here we report the discovery, from the Late Pleistocene of Flores, Indonesia, of an adult hominin with stature and endocranial volume approximating 1 m and 380 cm , respectively—equal to the smallest-known australopithecines. The combination of primitive and derived features assigns this hominin to a new species, Homo floresiensis. The most likely explanation for its existence on Flores is long-term isolation, with subsequent endemic dwarfing, of an ancestral H. erectus population. Importantly, H. floresiensis shows that the genus Homo is morphologically more varied and flexible in its adaptive responses than previously thought. [ABSTRACT FROM AUTHOR]

Island colonization and subsequent dwarfing of Pleistocene proboscideans is one of the more dramatic evolutionary and ecological occurrences, especially in situations where island populations survived end-Pleistocene extinctions whereas those on the nearby mainland did not. For example, Holocene mammoths have been dated from Wrangel Island in northern Russia. In most of these cases, few details are available about the dynamics of how island colonization and extinction occurred. As part of a large radiocarbon dating project of Alaskan mammoth fossils, I addressed this question by including mammoth specimens from Bering Sea islands known to have formed during the end-Pleistocene sea transgression. One date of 7,908 ± 100?yr?bp (radiocarbon years before present) established the presence of Holocene mammoths on St Paul Island, a first Holocene island record for the Americas. Four lines of evidence-265 accelerator mass spectrometer (AMS) radiocarbon dates from Alaskan mainland mammoths, 13 new dates from Alaskan island mammoths, recent reconstructions of bathymetric plots and sea transgression rates from the Bering Sea-made it possible to reconstruct how mammoths became stranded in the Pribilofs and why this apparently did not happen on other Alaskan Bering Sea islands. [ABSTRACT FROM AUTHOR]

Many records of tropical sea surface temperature and marine productivity exhibit cycles of 23?kyr (orbital precession) and 100?kyr during the past 0.5?Myr (refs 1-5), whereas high-latitude sea surface temperature records display much more pronounced obliquity cycles at a period of about 41?kyr (ref. 6). Little is known, however, about tropical climate variability before the mid-Pleistocene transition about 900?kyr ago, which marks the change from a climate dominated by 41-kyr cycles (when ice-age cycles and high-latitude sea surface temperature variations were dictated by changes in the Earth's obliquity) to the more recent 100-kyr cycles of ice ages. Here we analyse alkenones from marine sediments in the eastern equatorial Pacific Ocean to reconstruct sea surface temperatures and marine productivity over the past 1.8?Myr. We find that both records are dominated by the 41-kyr obliquity cycles between 1.8 and 1.2?Myr ago, with a relatively small contribution from orbital precession, and that early Pleistocene sea surface temperatures varied in the opposite sense to local annual insolation in the eastern equatorial Pacific Ocean. We conclude that during the early Pleistocene epoch, climate variability at our study site must have been determined by high-latitude processes that were driven by orbital obliquity forcing. [ABSTRACT FROM AUTHOR]

A key pacemaker of ice ages on the Earth is climatic forcing due to variations in planetary orbital parameters. Recent Mars exploration has revealed dusty, water-ice-rich mantling deposits that are layered, metres thick and latitude dependent, occurring in both hemispheres from mid-latitudes to the poles. Here we show evidence that these deposits formed during a geologically recent ice age that occurred from about 2.1 to 0.4 Myr ago. The deposits were emplaced symmetrically down to latitudes of ~30°-equivalent to Saudi Arabia and the southern United States on the Earth-in response to the changing stability of water ice and dust during variations in obliquity (the angle between Mars' pole of rotation and the ecliptic plane) reaching 30-35°. Mars is at present in an ‘interglacial’ period, and the ice-rich deposits are undergoing reworking, degradation and retreat in response to the current instability of near-surface ice. Unlike the Earth, martian ice ages are characterized by warmer polar climates and enhanced equatorward transport of atmospheric water and dust to produce widespread smooth deposits down to mid-latitudes. [ABSTRACT FROM AUTHOR]

Presents an analysis of a continuous sediment record from Lake Baikal, Siberia, Russia which revealed a continuous interglacial diatom assemblage, a stable littoral benthic diatom assemblage and lithogenic sediments with interglacial characteristics. Cause of the insolation gradients contributing to global glacial inceptions and terminations; Analysis of the mid-Pleistocene sedimentary record at the pelagic BDP-96drill site; Examination of the rock-magnetic signature.

Discusses efforts to simulate the conditions which caused the last ice age, 115,000 years before the present. Failure of efforts to simulate this glaciation using global atmospheric models, when forced by insolation changes only; The importance of feedback effects, such as changes in ocean circulation, in creating perennial snow cover.

Analyzes backscatter images and sub-bottom profiler records obtained during the 1999 expedition of the SCICEX submarine in the Arctic Ocean. Discovery of multiple bedforms indicative of glacial scouring and moulding of the sea floor, combined with large-scale erosion of submarine ridge crests; How these distinct glaciogenic features demonstrate that immense, Antarctic-type ice shelves of up to 1 kilometer thick and hundreds of kilometers long existed in the Arctic Ocean during Pleistocene glaciations.

Shows that the geochemistry of the Pleistocene basalts from Logudoro, Sardinia is compatible with the remelting of ancient ocean plateau material that has been recycled into the mantle. Argument that the EM-1 lava source is essentially free of sedimentary materials; Storage of plume heads in the deep mantle through time offering a convenient explanation for the persistence of chemical and mineralogical layering in the mantle.

Examines the phase evolution of precession and semiprecession cycles in the tropical and extra-tropical Atlantic Ocean. Purpose of the study to explain changes in the Earth's glacial cycles during the Pleistocene epoch; Conclusion that heat flow across the equator to higher latitudes strengthened the semiprecession cycle in the Northern Hemisphere and triggered the transition to sustained glacial cycles.

Dates the penultimate deglaciation in a record from the Bahamas using a uranium-thorium isochron technique. Theory on the cause of Ice Age climate cycles; June Northern hemisphere insolation; Potential alternative driving mechanisms for the Ice Age cycles.

Presents the analysis of an almost complete human male pelvis, Pelvis 1, from the Middle Pleistocene site of Sima de los Huesos in Sierra de Atapuerca, Spain. Other fossils from this site, and their dating and classification; Details about the pelvis; How a female pelvis would differ; Body mass of the male; Encephalization quotients compared with Neanderthals and modern humans.

Presents research which showed that millennial-scale oscillations in climate occurred over one million years ago. Records of variations in the Earth's climate; Possible tie of climate shifts to alterations in the mode of ocean thermohaline circulation; Nature of climate conditions one million years ago; Climate instability a long-term and pervasive trait of Earth's climate.

Presents research which dated the emplacement of a large turbidite in the Balearic Basin of the western Mediterranean. How large-volume turbidites occur; Effects of turbidites on the environment and atmosphere; Use of accelerator-mass-spectrometry radiocarbon dating; Unique features of turbidite studied; Details on dating.

Presents research which created two simple models that successfully simulate each glacial-interglacial cycle over the late Pleistocene epoch with the correct time and amplitude. Earth's climate over the past million years; Factors in glacial-interglacial cycles; Astronomical theory of climate.

Demonstrates that two independent methods of body-mass estimation yield concordant results when applied to Pleistocene Homo specimens. The comparison of body mass of Pleistocene Homo to living humans; The brain mass in late archaic H. sapiens (Neanderthals).

Presents high-precision thermal-ionization mass spectrometric thorium-230 (230Th) for a comprehensive suite of speleothem samples from the Bahamas. Influence of Pleistocene sea levels on climate; Record of maximum elevation; Importance of regional paleoclimatic change in the termination of speleothem growth.

Reveals that the climate in Greenland during the last interglacial period was characterized by a series of severe cold periods lasting from decades to centuries. Isotope and chemical analyses of the Greenland Ice-Core Project from Summit, Greenland; Effects of future global warming.

Presents evidence for a short but intense cold period in eastern North America, pre-dating the Younger Dryas, revealed by analyzing the organic, pollen and midge content of lake sediments at very high resolution. Killarney Oscillation; Gerzensee Oscillation in Switzerland; Accelerator mass spectrometry (AMS); Loss-on-ignition (LOI); Age estimates for Killarney Oscillation; LOI curves for sediment from lakes in Maritime Canada; More.

Presents evidence that, in the region of the French Vosges, the regional ice sheet advanced during the early part of the last glacial cycle. Concludes that the glacial maximum may not have occurred at the same time worldwide, contrary to previous assumptions.

Reports on palaeoclimate data that indicates both the high- and low-latitude North Atlantic regions were characterized by at least three synchronous periods of abrupt climate change during the last glacial-to-interglacial transition. Milankovitch forcing; Caribbean and Gulf of Mexico regions; Observed versus simulated palaeoclimatic change.

The article focuses on the research on ocean circulation in a warming climate. Accordingly, findings show that the Last Glacial Maximum (LGM) had stronger winds which fit to the common observation that it is windier in the winter than in the summer because there is greater thermal contrast within the atmosphere in the winter hemisphere. Moreover, the paper cited several observations that predict that oceans' circulation will weaken in response to global warming, but the warming at the end of the last ice age suggests a different outcome. However, by studying these observations, it is clear that large circulation changes took place and it seems unlikely that circulation changes of this magnitude could have happened without substantial changes in the wind forcing.

Investigates the causes of the extinction of large animals during the Late Pleistocene and Holocene period in Australia. Factors that impedes the study of the extinction of megafaunas; Dating technique used to determine the period of human arrival in Australia; Conclusions of the study.

Suggests that high glacial dust loading may have caused significant, episodic regional warming downwind of major Asian and ice-margin dust sources during the last glacial period. The association of abrupt changes in dust loading with the Dansgaard-Oeschger and Heinrich climate events and with glacial termination; The suggestion that dust-induced warming may have played a role in triggering large shifts in Pleistocene climate.

Presents a stable-isotope record for the full length of the Greenland Ice-core Proiject Summit ice core. Non-confinement of climate instability to the last glaciation; Saale-Holstein glacial cycle; Delay in the melting of the Saalean ice sheets in America and Eurasia; Rapid reorganization in the climate of the North Atlantic region.

The article reports on ice-age ocean circulation. It specifically refers to climate simulations based on an ocean model. It is stated that the model suggests reasons why existing climate models have failed to deliver a clear picture of ocean circulation during the last ice age. It is reported that simulating the climate of the most recent ice age is a significant test for models which are used to project the climate of the future.

The article focuses on a controversial idea that suggests that a big space rock exploded on or above North America at the end of the last ice age. The new evidence comes in the form of geochemical analysis of sedimentary layers at 25 archaeological sites across North America, 9 of them Clovis. Critics about the theory is also provided.

The article presents an insight into the ecology of extinctions as a result of the ice-age. The extinction of a wide variety of large mammals are thought to have been the result of the ice-age. Mammals such as the woolly mammoths have been searched for after its survival on Wrangel Island in the northeastern Siberian Arctic. The Irish Elk is another species whose investigation for extinction is still on through a number of techniques as the radiocarbon dating method. Theories for both the expansion and the extinction of Irish elk populations, for instance, often focus on the animals' huge antlers.

Examines the new ice core from Greenland yielding the first high-resolution picture of the start of the last ice age in the Northern Hemisphere. Prevention of the cores from revealing either the onset of ther glacial period or events during the preceding warm interglacial period by structural disturbance of the deepest ices; Location of the North Greenland Ice Core Project core in a volcanic center; Reduction of the thinning of deep ice layers.

Reveals a record of Earth's climate over the eight past ice ages and their associated interglacial periods from an ice core in Antarctica. Evidence for the past climatic instability of the last glacial cycle; Dome C record; Shift in the pattern of glacial cycles that occurred without changes in the varying seasonal distribution of sunlight that is believed to pace the ice ages.

Both Mars and Earth have experienced ice ages in geologically recent times. Coincidence of the phenomenon on two planets will further the scientific quest to answer the question of how ice ages originate. [ABSTRACT FROM AUTHOR]

Focuses on the reconstruction of temperatures in the Atlantic Ocean during the last age which is 21,000 years prior to 2003. Factors influencing climate changes; Mechanisms of global change; Magnitude and direction of ice-age temperatures; Dynamics of air-sea interaction in the tropics; Sensitivity of global system to changing greenhouse gases.

Discusses the theory of `snowball Earth' which proponents say happened at least twice during the Cryogenian period of the late Precambrian. Description of the effects of snowball events on the biosphere; Arguments that oppose a theory posited by William Hyde, et al; Other possible outcomes associated with snowball earth. INSET: How to make an animal -- indirectly.

Reports that uranium-thorium dating of the end of the Pleistocene epoch has caused scientists to reconsider which part of the climate system drives severe glaciation. Theories regarding the causes of the Ice Age; Effects of the Earth's orbital cycles; Concerns over the El Nino weather phenomenon.

Discusses what causes ice ages, and other episodes of violent climate change, according to a report by T. Blunier et al in the same issue. Their efforts to cross-date isotope records in ice cores from Greenland and Antarctica to within a few centuries; How they took advantage of the rapid and large swings in the methane concentration of the atmosphere during the last glacial period.

Focuses on the isotopic, chemical and physical analysis of ice cores from Greenland. High-resolution data on methane and oxygen; Bipolar view of the earth's climate; Apparent instabilities in the climate of the last interglacial period as artefacts; Link between the Greenland, Antarctic and marine sediment palaeoclimate records.

The article presents the views of several geologists who favored the redefinition of the quaternary base and lowering of the pleistocene base. According to Philip Gibbard of the University of Cambridge, the 800,000-year slice into the pleistocene is just correcting the mistake made 25-30 years ago defining pleistocene base at 1.8 million years ago. Stan Finney notes that geologic timescale is fundamental for expressing the history of the earth.

The article discusses how ancient ooze from the bottom of the Pacific Ocean can provide evidence that the deep ocean sequestered vast amounts of carbon dioxide (CO2) during a previous ice age which cooled the planet Earth. Topics include research by Samuel Jaccard and colleagues who obtained data from trace elements within ancient ooze and revised a previous hypothesis regarding the nutrient dynamics of the ocean.

This article presents information on the butterfly Polyommatus coridon. This distinctive species is found in the northern half of Europe. Two researchers, T. Schmitt and G.M. Hewitt used this species, to conclude that the butterflies' location in Europe, determined by past climatic events, reflects their genetic diversity, and also their predisposition to population decline. There are two major lineages of this chalk-hill blue colored butterfly in Europe, one is found in the east, the other in the west. After the last ice age, these groups probably emerged from two regions in the southern Mediterranean, and then underwent a northward postglacial colonization.

We have analysed three fossilized trackways of human footprints in a zeolite-rich pyroclastic flow dated to 385,000-325,000 years ago (kyr), discovered along the western margin of the Roccamonfina volcanic complex in southern Italy. We believe that these tracks are the oldest human footprints found so far and that they were made by hominids who had a fully bipedal, free-standing gait, using their hands only to steady themselves on the difficult descent. [ABSTRACT FROM AUTHOR]