after 20 years a taphonomic re evaluation of nahal hadera v an epipalaeolithic site on the israeli coastal plain we carried out a detailed taphonomic study of the faunal remains from nahal hadera v nhv a large kebaran open air site on the northern coastal plain israel faunal remains were previously identified to bone element and species saxon martin bar yosef 1978 however nisp and mni values were calculated based on teeth and epiphyses only in this study we identified the maximum number of skeletal elements including head fragments vertebrae ribs carpals tarsals and shaft fragments further analyses included search for various bone surface modifications and the study of mode of bone fragmentation we found minor loss of bones caused by various diagenetic processes and no signs of carnivore activity these results suggest that most of the bone destruction was caused during time of occupation probably for marrow consumption as indicated by mode of bone fragmentation absence of selective transport for gazelle gazella gazella and fallow deer dama mesopotamica the major prey species with 70 and 20 respectively is supported by homogeneous representation of head limb toe elements however the carcasses may have been processed before transport to the site thus a taphonomic analysis from nhv helps to illuminate the economy of nhv inhabitants and fine tunes our understanding of the depositional history of the site however it does not overthrow results of earlier research using classical methods

variability of el nino southern oscillation activity at millennial timescales during the holocene epoch the variability of el nino southern oscillation enso during the holocene epoch in particular on millennial timescales is poorly understood palaeoclimate studies have documented enso variability for selected intervals in the holocene but most records are either too short or insufficiently resolved to investigate variability on millennial scales1 2 3 here we present a record of sedimentation in laguna pallcacocha southern ecuador which is strongly influenced by enso variability and covers the past 12 000 years continuously we find that changes on a timescale of 2 8 years which we attribute to warm enso events become more frequent over the holocene until about 1 200 years ago and then decline towards the present periods of relatively high and low enso activity alternating at a timescale of about 2 000 years are superimposed on this long term trend we attribute the long term trend to orbitally induced changes in insolation and suggest internal enso dynamics as a possible cause of the millennial variability however the millennial oscillation will need to be confirmed in other enso proxy records

when felids and hominins ruled at olduvai gorge a machine learning analysis of the skeletal profiles of the non anthropogenic bed i sites abstract in the past twenty years skeletal part profiles which are prone to equifinality have not occupied a prominent role in the interpretation of early pleistocene sites on africa alternatively taphonomic studies on bone surface modifications and bone breakage patterns have provided heuristic interpretations of some of the best preserved archaeological record of this period namely the olduvai bed i sites the most recent and comprehensive taphonomic study of these sites dominguez rodrigo et al 2007a showed that flk zinj was an anthropogenic assemblage in which hominins acquired carcasses via primary access that study also showed that the other sites were palimpsests with minimal or no intervention by hominins the flk n flk nn and dk sequence seemed to be dominated by single agent mostly felid or multiple agent mostly felid hyenid processes the present study re analyzes the bed i sites focusing on skeletal part profiles machine learning methods which incorporate complex algorithms are powerful predictive and classification methods and have the potential to better extract information from skeletal part representation than past approaches here multiple algorithms via decision trees neural networks random forests and support vector machines are combined to produce a solid interpretation of bone accumulation agency at the olduvai bed i sites this new approach virtually coincides with previous taphonomic interpretations on a site by site basis and shows that felids were dominant accumulating agents over hyenas during bed i times the recent discovery of possibly a modern lion accumulated assemblage at olduvai gorge arriaza et al submitted provides a very timely analog for this interpretation

florida straits density structure and transport over the last 8000 years 1 the density structure across the florida straits is reconstructed for the last 8000 years from oxygen isotope measurements on foraminifera in sediment cores the oxygen isotope measurements suggest that the density contrast across the florida current increased over this time period the magnitude of this change corresponds to an increase in the geostrophic transport referenced to 800 m water depth of 4 sverdrups sv over the last 8000 years the spatial and seasonal distribution of incoming solar radiation due to changes in the earth s orbit has caused systematic changes in the atmospheric circulation including a southward migration of the intertropical convergence zone over the last 8000 years these changes in atmospheric circulation and the associated wind driven currents of the upper ocean could readily account for a 4 sv increase in the strength of the florida current we see no evidence in our data for dramatic changes in the strength of the atlantic meridional overturning circulation over this time period

diagnostic properties of hammerstone broken long bone fragments specimen identifiability and early stone age butchered assemblage interpretation abstract zooarchaeological assemblages in a variety of geographic and temporal contexts are dominated by fragmentary long bone specimens and precise identification of side skeletal element and bone portion underlie archaeological interpretations including specimen counts for skeletal part profiles minimum number of element mne and individual mni estimates actualistic hammerstone and anvil breakage of domestic goat limb bones was used to document how fragmentation impacts precise identification of skeletal specimens analysis of assemblage composition and reconstructions of butchery behavior specimens greater than 2 cm in size were assigned to categories that describe the precision with which side element upper intermediate and lower limb segment and long bone portion could be identified results suggest that specimen size is positively related to identifiability and more identifiable specimens tend to include epiphyses and relatively complete shaft circumferences most elements produced a similar number of fragments including highly identifiable ends that yield accurate skeletal part profiles mne and mni estimates however if density mediated destruction removes these specimens analysis of less identifiable shaft fragments significantly underrepresents element and individual abundance the number of identified limb specimens nisp mne and epiphysis to shaft ratios in fragmentary archaeological butchery assemblages suggest limb end underrepresentation deflates measures of assemblage abundance and reduces the behavioral resolution of butchery interpretations however zooarchaeological analyses can productively incorporate fragmentary less identifiable specimens when they define hypotheses that match the scale of archaeological data

high frequency of super cyclones along the great barrier reef over the past 5 000 years understanding long term variability in the occurrence of tropical cyclones that are of extreme intensity is important for determining their role in ecological disturbances1 2 3 4 5 for predicting present and future community vulnerability and economic loss6 and for assessing whether changes in the variability of such cyclones are induced by climate change7 our ability to accurately make these assessments has been limited by the short less than 100 years instrumented record of cyclone intensity here we determine the intensity of prehistoric tropical cyclones over the past 5 000 years from ridges of detrital coral and shell deposited above highest tide and terraces that have been eroded into coarse grained alluvial fan deposits these features occur along 1 500 km of the great barrier reef and also the gulf of carpentaria australia we infer that the deposits were formed by storms with recurrence intervals of two to three centuries8 9 10 11 and we show that the cyclones responsible must have been of extreme intensity central pressures less than 920 hpa our estimate of the frequency of such super cyclones is an order of magnitude higher than that previously estimated which was once every several millennia12 13 14 and is sufficiently high to suggest that the character of rainforests and coral reef communities were probably shaped by these events

pelagic sedimentation on an inactive gullied slope northwest providence channel bahamas abstract the southern flank of little bahama bank is a deep water carbonate slope into which a series of closely spaced canyons 10 200 m deep have been cut it is similar in morphology to many other slopes in the bahamas and these slopes are generally considered to be created by the erosion of downslope sediment gravity flows however little evidence for downslope sediment movement or associated erosion were found in the holocene or latest pleistocene sediments of the slope reported on here the sediments from water depths below 260 m consist of a uniform pelagic drape covering both the gullies and inter gully ridge tops high resolution seismic reflectors are not truncated along individual gully walls and the fine scale stratigraphy of the sediments recorded in glacial interglacial changes in the aragonite calcite ratio of the sediments is preserved in sediments from gullies and ridge tops it appears that for the last two to three glacial cycles there has been only minor downslope transport of sediment despite the gullied morphology erosion is not presently occurring on the slope

changing competition dynamics among predators at the late early pleistocene site barranc de la boella tarragona spain abstract the late early pleistocene site barranc de la boella provides an unparalleled opportunity to assess the context of the activities of the hominin populations that inhabited the iberian peninsula at 1 ma recently strong evidence for access to mammoth meat has been described at the pit 1 locality at the la mina and el forn excavation areas little evidence exists for the anthropogenic processing of macromammals however the presence of humans is recorded and the available evidence suggests these populations had access to several interesting resources by analysing and comparing five separate assemblages at barranc de la boella we assess the fluctuating presence of hominins and carnivores and the levels of competition among predators in each assemblage our analysis reveals different levels of competition intensity during the formation of assemblages when hominin groups were present as evidenced by the abundance and diversity of stone artefacts the analyses of skeletal component ratios indicate several competitive contexts and the greatest presence of hominin groups is associated with the most competitive scenarios the palaeoenvironment at barranc de la boella was rich in resources that hominins could exploit the presence of hominin and carnivore groups appears to have been higher in levels with more inferred competition this scenario supports prior research that concludes that carnivore abundance and highly competitive contexts were two constants in the lives of these hominin groups thus the criteria determining whether hominins could inhabit a given landscape were most likely related to the presence or absence of resources such as animal resources water and raw materials rather than the dynamics of the carnivore populations to which the hominins were able to become habituated

sediment resuspension over a continental shelf during hurricanes edouard and hortense the present comprehensive physical and optical measurements have captured sediment resuspension associated with two hurricanes edouard and hortense that passed over the coastal mixing and optics study site in the fall of 1996 sediment resuspension associated with hurricane edouard was forced by combined current and wave processes combined current wave bottom shear stresses exceeded 3 5 dyn cm 2 well above the shear stress for the observed resuspension which was determined to be 0 8 dyn cm 2 hortense sediment resuspension however was caused primarily by waves with little or no contribution from subtidal plus tidal currents combined current wave bottom shear stress reached 2 dyn cm 2 beam attenuation data reveal that bottom sediments were resuspended from 70 m depth to more than 30 m up into the water column during both hurricanes the relaxation of sediments to pre edouard conditions occurred at about the same time at all depths indicating advection and transport by subtidal currents analyses of optical data reveal that the resuspended sediments consisted mainly of detritus and relict pigments from the ocean bottom

geochemical evidence for enhanced productivity during s1 sapropel deposition in the eastern mediterranean the geochemistry of the youngest mediterranean sapropel layer suggests changes in productivity and water column oxygen conditions during sapropel deposition the ba enriched interval is broader than the organic carbon rich interval of this sapropel we suggest that the ba enriched horizon records the original thickness of the sapropel prior to subsequent partial oxidation the main carrier of ba is barite as microcrystals 0 5 5 m having a morphology characteristic of marine barite particularly abundant beneath high productivity regions ba concentrations do not change at the sapropel layer oxidation front and diagenetic barite crystals are absent thus the ba enriched layer reflects original oceanic conditions of increased biological productivity during sapropel deposition and not diagenetic ba remobilization paleoredox indicators point to restricted oxygenated bottom water but not to fully anoxic conditions detrital elements within this layer indicate a lower eolian terrigenous input enhanced humidity and increased precipitation runoff thus likely higher nutrient supply supporting table is available on diskette or via anonymous ftp from kosmos agu org directory apend username anonymous password guest diskette may be ordered by mail from agu 2000 florida ave n w washington dc 20009 or by phone at 800 966 2481 15 00 payment must accompany order

new excavations at the flk zinjanthropus site and its surrounding landscape and their behavioral implications renewed excavations at flk zinj and its surrounding landscape have yielded valuable information regarding its paleoecological situation and the prehistoric behavioral function of the site the density of materials at the main cluster of the site excavated by leakey contrasts with the bone and lithic scatters surrounding the site the location of flk zinj situated a few hundred meters away from a freshwater spring would have enabled hominins access to water plants and game the appeal of the spot for hominins also explained by the presence of a wooded habitat is confirmed by inferences of its redundant use prior and during the formation of the flk zinj paleosol as witnessed by materials accumulated both under and on the waxy clay deposit that constitutes the flk zinj stratum the single cluster nature of the site indicates central place behavior and evidence is provided that hominins occupied the site at a time of very low predation hazards in the area

isotopic spikes from tropical cyclones in surface waters opportunities in hydrology and paleoclimatology abstract the stable isotopic ratio of precipitation from tropical cyclones is very low compared to that of normal summer precipitation lawrence and gedzelman 1996 tropical storms allison and chantal made landfall in southeast texas in the summer of 1989 and dumped large amounts of rain isotope ratios of surface waters measured at five different sites decreased markedly after the passage and remained low for a few weeks the return of isotope values to normalcy following these storms varied from site to site reflecting differences among the hydrological environments during other summers from 1985 to 1993 isotope ratios of rains were higher and in the normal range calculations using air temperatures and oxygen isotope measurements of the surface waters show that organically precipitated fresh water carbonate should have recorded the two oxygen isotopic spikes produced by allison and chantal at all five sites this suggests that isotopic analysis of ancient fresh water fossil carbonate shells fossil mammal teeth or tree rings might be used to document past tropical cyclone activity

atlantic seasonal hurricane frequency part i el nino and 30 mb quasi biennial oscillation influences abstract this is the first of two papers on atlantic seasonal hurricane frequency in this paper seasonal hurricane frequency as related to e1 nino events during 1900 82 and to the equatorial quasi biennial oscillation qbo of stratospheric zonal wind from 1950 to 1982 is discussed it is shown that a substantial negative correlation is typically present between the seasonal number of hurricanes hurricane days and tropical storms and moderate or strong 15 cases el nin off the south american west coast a similar negative anomaly in hurricane activity occurs when equatorial winds at 30 mb are from an easterly direction and or are becoming more easterly with time during the hurricane season this association of atlantic hurricane activity with el nino can also be made with the southern oscillation index by contrast seasonal hurricane frequency is slightly above normal in non el nino years and substantially above normal when equatorial stratospheric winds blow from a westerly direction and or are bec

quaternary slope development of the western leeward margin of the great bahama bank abstract to date work on the great bahama bank s western leeward margin has centred chiefly on seismic scale expressions of carbonate sequences and systems tracts however periplatform slope sediments also exhibit very well developed cyclicity on scales of decimetres to several metres it is these small scale high frequency cycles within the larger scale facies successions of the quaternary which form the main topic of this paper previous studies have shown that the small scale cycles correlate to the orbitally forced high frequency sea level changes therefore these cycles should indicate how sea level has affected the slope development and thus platform margin evolution during this period through detailed high resolution sequence stratigraphy of the great bahama bank s leeward margin obtained via 18o isotope and mineralogical xrd analyses confined by u th dating and nannofossil bioevents a greater understanding of the bedding geometries within the pleistocene holocene seismic sequences and clues as to the nature of the slope development has been achieved the high resolution seismic profiles indicate that since the plio pleistocene change in geometry in which the great bahama bank developed into a rimmed platform continued steepening and subsequent progradation of the leeward margin has typified slope development during the quaternary which is described as an accretionary slope however on the basis of our observations we conclude that only the early to lower middle pleistocene section isotope stages 45 20 and the holocene isotope stage 1 of the leeward margin is accretionary this indicates that a degree of erosion and or by passing has occurred on the leeward margin since the lower middle pleistocene isotope stage 19 during the first part of this period isotope stages 19 12 erosion and or by passing occurred in the middle to lower slope regions and toe of slope by the end of the upper middle to late pleistocene phase isotope stages 11 2 erosion also occurred on the upper slope this erosion by currents at the toe of slope and oversteepening of the upper and middle slopes have led to back cutting upslope and resulted in the progressive retreat of the toe of slope towards the platform to the east however the rise in sea level since the last glacial maximum to its present day level has allowed high productivity on the platform top during the holocene and the deposition of a thick sediment wedge on the slope and sedimentation across the entire leeward flanks this has led to the redevelopment of an accretionary slope and continued westward progradation of the great bahama bank s western leeward margin

hurricane induced sediment transport in open shelf tropical systems an example from st croix u s virgin islands hurricane hugo passed directly over st croix on 17 september 1989 sustained winds in excess of 110 knots gusts to 165 knots and waves 6 7 m in height accompanied the storm along the north coast wave height was lower ca 3 4 m due to the leeward position of the shelf in the deeper reefs at cane bay and salt river damage was confined primarily to the soft bodied benthic community e g sponges gorgonians coral damage was much less severe largely because of the buffering effects of the water column the greatest change observed after the storm was wholesale flushing of sand from shelf edge areas in salt river submarine canyon a minimum of 2 million kg of sediment were flushed into deeper water the transport rate associated with the storm was eleven orders of magnitude above that measured during fair weather and the volume of sediment that was removed from the canyon equalled roughly a century of normal sediment accumulation at cane bay 336 000 kg of sediment were flushed from a single channel with similar amounts removed from adjacent breaks in the shelf edge reef a current meter in salt river submarine canyon provided information on the timing and intensity of the oceanographic processes related to hurricane hugo as the storm approached waves piled water against the shoreface and in salt river bay as the storm passed over st croix the change in wind direction followed by a decrease in wave height triggered a release of water trapped in the bay and along the adjacent shoreline by waves earlier in the storm for a period of 4 6 hours net down canyon currents reaching 2 m s and oscillatory flows up to 4 m s occurred along the base of the western canyon wall removing up to 2 m of sand similar events were likely responsible for the wholesale removal of sand in eastern cane bay the paradoxical concurrence of wholesale sediment transport and low level reef damage is related to the protection from waves but not wind afforded by the north coast of st croix facing away from the direction of storm approach these observations and measurements provide our first opportunity to relate sediment export in such a high energy event to the physical processes that were responsible calculations based on post hugo measurements are in agreement with an earlier sediment budget for salt river canyon sediment export in cane bay exceeded the volume similarly predicted because such events are probably common on all exposed carbonate shelf margins storms like hurricane hugo are among the most important factors in the cycling of sediment through exposed open marine environments both now and in the geologic past the patterns of reef damage and sediment transport are much more complicated than previously envisioned and more thoughtful consideration of their variability and the processes responsible is essential to an understanding of the signature that will be left by major storms

lake sediment record of late holocene hurricane activities from coastal alabama coastal lake sediments contain a stratigraphically and chronologically distinct record of major hurricane strikes during late holocene time frederic a category 3 hurricane that struck the alabama coast on the gulf of mexico in 1979 left a distinct sand layer in the nearshore sediments of lake shelby as a result of storm tide overwash of beaches and dunes sediment cores taken from the center of lake shelby contain multiple sand layers suggesting that major hurricanes of category 4 or 5 intensity directly struck the alabama coast at ca 3 2 3 0 2 6 2 2 1 4 and 0 8 ka 14 c yr with an average recurrence interval of 600 yr the alabama coast is likely to be struck by a category 4 or 5 hurricane within the next century

a gis based approach to documenting large canid damage to bones abstract experimental studies of modern carnivore tooth marking patterns are integral to understanding the nature of carnivore involvement in archeological bone assemblages however modern bone damage data for most carnivore taxa are limited this is particularly true for canids this study presents bone damage data collected from feeding experiments conducted with mexican gray wolves canis lupus baileyi and red wolves canis rufus this is the largest experimental assemblage reported for canids to date the image analysis gis approach described by marean et al 2001 is expanded on here and used to document bone preservation and tooth mark distribution for the first time in a carnivore modified bone assemblage further we introduce the use of the arcgis spatial analyst to identify significant concentrations of bone modifications results show that the distribution of tooth pits varies considerably across elements as well as across different portions of the same element and that significant clusters of tooth pits occur on all long bones we suggest that with a large enough sample the gis spatial analyst can be a useful tool for analyzing the distribution of bone modifications with greater resolution than previous methods this method facilitates comparisons between experimental and fossil assemblages which may aid in identifying the timing of access to carcasses by carnivores involved in modifying fossil assemblages finally the use of this rigorous methodology is a step toward increasing standardization in methods of taphonomic analysis

evidence from the florida straits for younger dryas ocean circulation changes 1 the waters passing through the florida straits today reflect both the western portion of the wind driven subtropical gyre and the northward flow of the upper waters which cross the equator compensating north atlantic deep water export as part of the large scale atlantic meridional overturning circulation it has been postulated from various lines of evidence that the overturning circulation was weaker during the younger dryas cold event of the last deglaciation we show here that the contrast in the oxygen isotopic composition of benthic foraminiferal tests across the florida current is reduced during the younger dryas this most likely reflects a decrease in the density gradient across the channel and a decrease in the vertical shear of the florida current this reduced shear is consistent with the postulated reduction in the atlantic meridional overturning circulation we find that the onset of this change in density structure and flow at the start of the younger dryas is very abrupt occurring in less than 70 years

reconstructing 7000 years of north atlantic hurricane variability using deep sea sediment cores from the western great bahama bank q1 enso show abrupt changes around 6000 yrs b p but most coastal sedimentary records do not span this time period establishing longer records is essential for understanding mid holocene patterns of storminess and their climatic drivers which will lead to better forecasting of how climate change over the next century may affect tropical cyclone frequency and intensity storms are thought to be an important mechanism for transporting coarse sediment from shallow carbonate platforms to the deep sea and bank edge sediments may offer an unexplored archive of long term hurricane activity here we develop this new approach reconstructing more than 7000 years of north atlantic hurricane variability using coarse grained deposits in sediment cores from the leeward margin of the great bahama bank high energy event layers within the resulting archive are 1 broadly correlated throughout an offbank transect of multi cores 2 closely matched with historic hurricane events and 3 synchronous with previous intervals of heightened north atlantic hurricane activity in overwash reconstructions from puerto rico and elsewhere in the bahamas lower storm frequency prior to 4400 yrs b p in our records suggests that precession and increased nh summer insolation may have greatly limited hurricane potential intensity outweighing weakened enso and a stronger west african monsoon factors thought to be favorable for hurricane development

leading tropical modes associated with interannual and multidecadal fluctuations in north atlantic hurricane activity abstract interannual and multidecadal extremes in atlantic hurricane activity are shown to result from a coherent and interrelated set of atmospheric and oceanic conditions associated with three leading modes of climate variability in the tropics all three modes are related to fluctuations in tropical convection with two representing the leading multidecadal modes of convective rainfall variability and one representing the leading interannual mode enso the tropical multidecadal modes are shown to link known fluctuations in atlantic hurricane activity west african monsoon rainfall and atlantic sea surface temperatures to the tropics wide climate variability these modes also capture an east west seesaw in anomalous convection between the west african monsoon region and the amazon basin which helps to account for the interhemispheric symmetry of the 200 hpa streamfunction anomalies across the atlantic ocean and africa the 200 hpa divergent wind anomalies and both the structure and spatial scale

highstand versus lowstand deposition on carbonate platform margins insight from quaternary foreslopes in the bahamas abstract examples of both highstand and lowstand deposition have been identified on the upper platform slopes of the tongue of the ocean bahamas highstand deposits consist of a thick wedge of fine grained skeletal and non skeletal sands and carbonate muds derived predominantly from the platform and deposited on slopes of 25 28 these sediments were deposited subsequent to platform flooding and may be more than 30 m thick along open leeward margins in contrast lowstand deposits consists of coarse skeletal sands gravels and boulders deposited on primary depositional slopes of 35 45 these sediments were derived from fringing reefs along the marginal escarpment and deposited during the initial rise of sea level following the last lowstand these variations in depositional character result in a distinctive signature of highstand versus lowstand deposition for steep sided platforms and further elucidate the response of carbonate platforms to high magnitude 5th order scale 20 000 yrs fluctuations in sea level

postglacial changes in el nino and la nina behavior paleoclimate reconstructions suggest distinctive changes in the el nino southern oscillation enso the dominant mode of tropical climate variability over the last glacial cycle and throughout the holocene however to the best of our knowledge no studies provide parallel reconstructions of warm el nino and cold la nina phase variability thus precluding distinction between variations in enso activity and the mean state of the tropical pacific here we provide the first such records generated using molecular organic geochemical proxies in a sediment core from the peru margin region the opposing influences of el nino and la nina on coastal upwelling and phytoplankton community structure produce distinct sedimentary sterol records describing the evolution of each enso phase we document changes in surface ocean productivity on the peru margin over the past 16 ka that indicate enhanced la nina like conditions alone during deglaciation but concomitant increases in both el nino and la nina activity during the past 2 ka we propose that the preponderance of la nina like conditions prior to 11 5 ka reflects the influence of waning glacial boundary conditions by contrast warm and cold phase covariability during the late holocene suggests centennial scale changes in enso activity rather than the pacific mean state driven by tropical insolation

characteristics of low frequency sea surface temperature fluctuations in the tropical atlantic abstract sea surface temperature anomalies in the tropical atlantic ocean are reexamined to investigate an apparent low frequency oscillation that has been described as a fluctuating dipole structure with poles north and south of the equator and a node near the itcz using principal components rotated by the varimax method and simple correlations of area averaged temperatures we show that during the 1964 88 interval sst anomalies north and south of the itcz are not significantly correlated therefore the low frequency variation with an apparent decadal period observed in the sst gradient across the itcz during 1964 88 does not arise from temporally coherent and out of phase fluctuations in each hemisphere and cannot be characterized as a dipole

holocene atlantic climate variations deduced from carbonate periplatform sediments leeward margin great bahama bank a marine sediment core from the leeward margin of great bahama bank gbb was subjected to a multiproxy study the aragonite dominated core md992201 comprises the past 7230 years in a decadal time resolution and shows sedimentation rates of up to 13 8 m kyr aragonite mass accumulation rates age differences between planktonic foraminifera and aragonite sediments and temperature distribution are used to deduce changes in aragonite production rates and paleocurrent strengths aragonite precipitation rates on gbb are controlled by exchange of carbonate ions and co2 loss due to temperature salinity conditions and biological activity and these are dependent on the current strength paleocurrent strengths on gbb show high current velocities during the periods 6000 5100 years bp 3500 2700 years bp and 1600 700 years bp lower current speeds existed during the time intervals 5100 3500 years bp 2700 1600 years bp and 700 100 years bp bahamian surface currents are directly linked to the north atlantic atmospheric circulation and thus periods with high low current speeds are proposed to be phases of strong weak atmospheric circulation

sedimentary evidence of hurricane strikes in western long island new york 1 evidence of historical landfalling hurricanes and prehistoric storms has been recovered from backbarrier environments in the new york city area overwash deposits correlate with landfalls of the most intense documented hurricanes in the area including the hurricanes of 1893 1821 1788 and 1693 a d there is little evidence of intense hurricane landfalls in the region for several hundred years prior to the late 17th century a d the apparent increase in intense hurricane landfalls around 300 years ago occurs during the latter half of the little ice age a time of lower tropical sea surface temperatures multiple washovers laid down between 2200 and 900 cal yr b p suggest an interval of frequent intense hurricane landfalls in the region our results provide preliminary evidence that fluctuations in intense hurricane landfall in the northeastern united states were roughly synchronous with hurricane landfall fluctuations observed for the caribbean and gulf coast suggesting north atlantic wide changes in hurricane activity

gulf stream density structure and transport during the past millennium the gulf stream transports approximately 31 sv 1 sv 10 6 m 3 s 1 of water and 1 3 10 15 w of heat into the north atlantic ocean the possibility of abrupt changes in gulf stream heat transport is one of the key uncertainties in predictions of climate change for the coming centuries given the limited length of the instrumental record our knowledge of gulf stream behaviour on long timescales must rely heavily on information from geologic archives here we use foraminifera from a suite of high resolution sediment cores in the florida straits to show that the cross current density gradient and vertical current shear of the gulf stream were systematically lower during the little ice age ad 1200 to 1850 we also estimate that little ice age volume transport was ten per cent weaker than today s the timing of reduced flow is consistent with temperature minima in several palaeoclimate records implying that diminished oceanic heat transport may have contributed to little ice age cooling in the north atlantic the interval of low flow also coincides with anomalously high gulf stream surface salinity suggesting a tight linkage between the atlantic ocean circulation and hydrologic cycle during the past millennium

carbonate platform flanks slope angle and sediment fabric more than 20 examples of fossil carbonate platform systems were compared for slope angle and sediment fabric plots of slope angle versus sediment fabric show that grainy non cohesive mud free sediments build steeper slopes than muddy cohesive sediments examples near the end members of grainy and muddy carbonate platform flanks are found in the triassic of the dolomites in northern italy and in the bahamas respectively they document the flank geometry and the processes readjusting the slope profile once the limiting slope angle is exceeded the grainy flank sediments in the dolomites modified by shearing and avalanching produce straight slope profiles with declivities up to 35 whereas the muddy bahamian flank sediments modified by large scale creep and rotational to translational sliding and slumping produce a concave upwards slope profile inclined at less than 4 the comparison between slope angle and sediment fabric indicates that the physical behaviour of sediments in the gravity field angle of shearing and mode of readjustment processes is linked to the composition of the slope sediment among the variables such as sea level subsidence climate plate motion and oceanographic setting windward leeward sediment fabric is suggested to be a major if not the major control on slope angle and slope curvature of carbonate platform flanks besides the recently documented tendency of carbonate sediments to build steeper slopes than siliciclastics this proposed relation sheds new light on the analysis and quantification of the variables influencing the geometry and depositional evolution of carbonate systems furthermore it provides an opportunity to deduce sediment composition from seismic lines and predict lithology prior to drilling

testing heterogeneity in faunal assemblages from archaeological sites tumbling and trampling experiments at the early middle pleistocene site of gesher benot ya aqov israel abstract the current paper reports an experimental case study to test the heterogeneity of faunal assemblages from the early middle pleistocene layers v 5 and v 6 of the gesher benot ya aqov acheulian site israel tumbling and trampling experiments were initiated to gain qualitative insight into processes of bone modification and to assess the timing of the biostratonomic chronology as it was assumed that both mechanisms were responsible for the formation of striations documented on the bone surfaces from the site the tumbling experiments mimicked sediment movement in a calm lacustrine shoreline environment whereas the trampling experiments investigate the role of animal hominin activities in dry muddy and wet environments models for the internal operational sequence of an abrasional process due to uni and multidirectional water movement and of a trampling scenario are presented these models are used for the interpretation of the fauna from gesher benot ya aqov

captive hyaena bone choice and destruction the schlepp effect and olduvai archaeofaunas abstract skeletal element representation at archaeological and palaeontological sites often differs from natural anatomical proportions at archaeological sites this pattern could result from hominid behaviour predepositional destructive or dispersive forces such as carnivore ravaging or post depositional destructive forces such as sediment compaction and leaching predepositional ravaging by carnivores is documented at several important plio pleistocene archaeofaunal assemblages flk zinjanthropus and flkn levels 1 2 here we present the first systematic and controlled experimental data on the effect of this process on skeletal element survival simulated archaeological assemblages of defleshed hammerstone broken and unbroken bones were created within a captive spotted hyaena enclosure and controlled numbers of hyaenas were allowed to ravage the sites vertebrae and pelves were nearly always chosen first for consumption by the hyaenas vertebrae and ribs were nearly always destroyed completely and pelves were destroyed 50 of the time limb bone ends were frequently destroyed while limb middle shaft fragments preserve nearly 100 of the original number of elements thus hominid discarded bone assemblages regardless of the original representation of elements can come to resemble the schlepp effect simply through post hominid hyaena scavenging the documented pattern at flk zinjanthropus and flkn1 2 of low frequencies of vertebrae ribs and pelves and high frequencies of limbs may be due to post hominid ravaging by hyaenas and not selective hominid transport of limb elements to the sites

tropical atlantic sea surface temperature variability and its relation to el nino southern oscillation past analyses of tropical atlantic sea surface temperature variability have suggested a dipole behavior between the northern and southern tropics across the intertropical convergence zone itcz by analyzing an improved 43 year 1950 1992 record of sst smith et al 1996 and other data derived from the comprehensive ocean atmosphere data set coads it is shown that the regions north and south of the itcz are statistically independent of each other at the seasonal to interannual timescales dominating the data confirming the conclusions of houghton and tourre 1992 some dipole behavior does develop weakly during the boreal spring season when there is a tendency for sst anomaly west of angola to be opposite of that in the tropical north atlantic it is further shown that tropical atlantic sst variability is corre lated with pacific e1 nifio southern oscillation enso variability in several regions the ma jor region affected is the north atlantic area of ne trades west of 40ow along 10on 20on and extending into the caribbean there about 50 80 of the anomalous sst variability is associ ated with the pacific enso with atlantic warmings occurring 4 5 months after the mature phases of pacific warm events an analysis of local surface flux fields derived from coads data shows that the enso related atlantic warmings occur as a result of reductions in the surface ne trade wind speeds which in turn reduce latent and sensible heat losses over the region in ques tion as well as cooling due to entrainment this enso connection is best developed during the boreal spring following the most frequent season of maximum enso anomalies in the pacific a region of secondary covariability with enso occurs along the northern edge of the mean itcz position and appears to be associated with northward migrations of the itcz when the north at lantic warmings occur although easterly winds are intensified in the western equatorial atlantic in response to pacific warm events they do not produce strong local changes in sst contrary to expectations from studies based on equatorial dynamics these teleconnected wind anomalies do not give rise to significant correlations of sst in the gulf of guinea with the pacific enso as the teleconnection sequence matures strong se trades at low southern latitudes follow the de velopment of the north atlantic sst anomaly and precede by several months the appearance of weak negative sst anomalies off angola and stronger positive anomalies extending eastward from southern brazil along 15o 30os

sedimentary evidence of intense hurricane strikes from new jersey nine vibracores from the backbarrier marsh at whale beach new jersey reveal three large scale overwash deposits associated with historic and prehistoric storms the uppermost and smallest overwash fan was deposited in the ash wednesday northeaster of march 5 8 1962 a second more substantial overwash fan between 100 and 35 cm depth dates to the late eighteenth or early nineteenth century this fan was most likely deposited during the 1821 hurricane the only intense hurricane to make landfall in new jersey in the past 350 yr a third larger overwash fan between 200 and 300 cm depth was deposited between a d 1278 and 1438 and is likely the result of a prehistoric intense hurricane strike the combination of historical and stratigraphic evidence indicates that two intense hurricanes winds 50 ms 21 have likely made landfall on the southern new jersey coast in the past 700 yr resulting in an annual landfall probability of 0 3

accumulation of bank top sediment on the western slope of great bahama bank rapid progradation of a carbonate megabank high resolution seismic profiles and submersible observations along the leeward slope of western great bahama bank show large scale export of bank top sediment and rapid progradation of the slope during the holocene a wedge shaped sequence up to 90 m thick is present along most of the slope and consists of predominantly aragonite mud derived from the bank since flooding of the platform 6 8 ka total sediment volume of the slope sequence is 40 80 that of holocene sediment currently retained on the bank maximum rates of vertical accumulation and lateral progradation are 11 15 m ka and 80 110 m ka respectively 10 to 100 times greater than previously known for periplatform muds slope deposition of exported mud during sea level highs appears to have been a major mechanism for the westward progradation of great bahama bank throughout the quaternary this may provide a critical modern analogue for ancient progradational margins

experimental archaeology in a mid latitude periglacial context insight into site formation and taphonomic processes abstract experiments have been carried out at two sites in periglacial maat 0 c and alpine maat 4 c contexts in the pyrenees including open air and cave loci to document in detail the role of site formation processes and taphonomic agents in the degradation of archaeological assemblages in both sites the experimental cells have undergone significant changes over the five years of measurements these are marked by slow downslope creep of lithic artefacts due to solifluction rain creep and the impact of debris fallen from the wall in the cave the behaviour of bone material was significantly different from that of lithics due to the activity of scavengers this was responsible for scattering a high proportion of bone remains and displacements were typically significant such activity was also responsible for a high number of bone elements being lost 1 3 to 2 3 of the bones weathering mostly cracking and exfoliation also affected dry bone material in the open air cells the measurements have highlighted the specific nature of the cave context which plays a protective role for bone remains against meteoric agents the talus at the entrance of the cavity was also characterized by a strong spatial heterogeneity in sedimentary processes which may generate a differential preservation of the assemblages

measuring the post depositional destruction of bone in archaeological assemblages abstract post depositional processes have affected most archaeozoological assemblages often causing fragmentation or destruction of bone which can vary by assemblage and hamper interpretations of the original element representation klein cruz uribe 1984 the analysis of animal bones from archaeological sites chicago university of chicago press prior to performing interassemblage comparisons analysts must first assess the post depositional destruction for each assemblage hammerstone breakage and hyaena ravaging experiments show that compact bones carpals tarsals fibulae are rarely fragmented therefore fragmentation of these bones in archaeozoological assemblages should be the result of post depositional destruction a completeness index for compact bones provides a description of the magnitude of post depositional destruction because the completeness index is independent of differential fragmentation and transport by bone collectors and quantification variation between researchers the efficacy of the completeness index for showing varing completeness of archaeological bone is demonstrated by comparing two late pleistocene archaeological sites in kenya when guided by experimental results the completeness index allows an evaluation of the impact of post depositional destruction on the two kenyan assemblages published archaeozoological reports must provide a measure of post depositional destruction or else the usefulness of the data for comparative analysis is compromised

biotic and abiotic processes affecting the formation of bk level 4c bed ii olduvai gorge and their bearing on hominin behavior at the site abstract excavations at bk have provided insights into the behavior of early hominins through the study of several archaeological levels the present study shows the results for a new archaeological sub level bk4c the main goal is to contribute to the knowledge of the different taphonomic processes that shaped bk4c and to better understand the role played by hominins in its formation due to the presence of a fluvial depositional context and a slight channel in bk4c a spatial analysis has been applied in order to determine the impact caused by water flows we conclude that water played a role in the rearrangement of the assemblage however the spatial properties of the assemblage indicate a limited impact of post depositional disturbance processes supporting the autochthonous nature of the site the taphonomic study of this sub level indicates that hominins had a primary role in the accumulation bulk defleshing and demarrowing of carcasses bk4 assemblages bk4b and bk4c indicate a repeated occupation of the site for short time periods this is interpreted by the overall fast sedimentation recorded in the fluvial system and the paucity of highly weathered bones showing extensive periods of sub aerial exposure in between sedimentary episodes the site functionality is potentially different from that inferred for earlier oldowan periods where sites were smaller and showed less marked spatial clustering of lithics and stone tools caused by hominin behavior

akhalkalaki the taphonomy of an early pleistocene locality in the republic of georgia as part of our investigations into the potential of the republic of georgia for providing information on early hominin occupation of eurasia we report here on akhalkalaki a large late early pleistocene locality located along the lower slopes of a miocene andesitic cone originally excavated in the 1950s as a palaeontological site it was re opened in the 1990s and stone tools were found associated with the fauna suggesting that it is also an archaeological occurrence excavations in the 1950s and 1990s uncovered thousands of bones of an early galerian fauna including the remains of new species of hippopotamus equus and canis vekua 1962 1987 and dominated by the remains of equus

offbank transport of carbonate sands along open leeward bank margins northern bahamas abstract vigorous offbank transport of carbonate sands occurs along the west facing leeward open margins of little and great bahama bank large offbank oriented sand waves thick sand bodies covering reefs and shallow water sands mostly non skeletal obtained from adjacent deep flanks all demonstrate the existence of this shallow to deep pathway of sediment transport a variety of data suggests that transport occurs during storms and not during normal tidal current fluctuations an abundance of composite grains as well as vertical sequences of submarine cemented horizons seen via seismic profiling within the marginal sand bodies indicate cyclic periods of relative quiescence followed by moments of intense sediment movement current meter data obtained during six weeks of low wind activity show that critical threshold velocities for sand transport are only barely exceeded during portions of the tidal cycle these flows coupled with higher frequency bottom currents generated by surface gravity waves winnow the sands but do not provide significant net offbank transport offbank sand transport provides material to the shallow and deep bank margins enabling them to expand during sea level highstands each sea level fluctuation is likely to produce within the shallow margins a vertical sequence of basal reefs covered by a thick non skeletal calcarenite capped by a subaerially exposed diagenetically altered surface shallow water sands carried off the marginal escarpment help to construct deep flanks and large sediment drifts

florida current surface temperature and salinity variability during the last millennium surface water d 18 ow near dry tortugas increased 0 4 during the course of the little ice age lia 1200 1850 a d equivalent to a salinity increase of 0 8 1 5 on the great bahama bank where surface waters are influenced by the north atlantic subtropical gyre d 18 ow increased by 0 3 during the last 200 years although a portion 0 1 of this shift may be an artifact of anthropogenically driven changes in surface water sco2 the remaining d 18 ow signal implies a 0 4 1 increase in salinity after 200 years b p the simplest explanation of the d 18 ow data is southward migration of the atlantic hadley circulation during the lia scaling of the d 18 ow records to salinity using the modern low latitude d 18 ow s slope produces an unrealistic reversal in the salinity gradient between the two sites only if d 18 ow is scaled to salinity using a high latitude d 18 ow s slope can the records be reconciled variable atmospheric 14 c paralleled dry tortugas d 18 ow suggesting that solar irradiance paced centennial scale migration of the inter tropical convergence zone and changes in florida current salinity during the last millennium citation lund d c and w curry 2006 florida current surface temperature and salinity variability during the last millennium paleoceanography 21 pa2009 doi 10 1029 2005pa001218

coherent high and low latitude climate variability during the holocene warm period a faunal record of sea surface temperature sst variations off west africa documents a series of abrupt millennial scale cooling events which punctuated the holocene warm period these events evidently resulted from increased southward advection of cooler temperate or subpolar waters to this subtropical location or from enhanced regional upwelling the most recent of these events was the little ice age which occurred between 1300 to 1850 a d when subtropical ssts were reduced by 3 to 4 c these events were synchronous with holocene changes in subpolar north atlantic ssts documenting a strong in phase link between millennial scale variations in high and low latitude climate during the holocene

variations in tropical cyclone genesis factors in simulations of the holocene epoch the thermodynamic factors related to tropical cyclone genesis are examined in several simulations of the middle part of the holocene epoch when the precession of earth s orbit altered the seasonal distribution of solar radiation and in one transient simulation of the millennium preceding the industrial era the thermodynamicpropertiesmostcrucialforgenesisdisplayabroadstabilityacrossbothperiods althoughbothorbital variations during the mid holocene mh 6000 years ago 6ka and volcanic eruptions in the transient simulation have detectable effects it is shown that the distribution of top of the atmosphere radiation 6ka altered the northern hemisphere seasonal cycle of the potential intensity of tropical cyclones in addition to slightly increasing the difference between middle tropospheric and boundary layer entropy a parameter that has been related to the incubation period required for genesis the southern hemisphere which receives more solar radiation during its storm season today than it did 6ka displays slightly more favorable thermodynamic properties during the mh than in the preindustrial era control surface temperatures over the ocean in both hemispheres respond to radiation anomalies more slowly than those in upper levels altering the thermal stability volcanism produces a sharp but transient temperature response in the last millennium simulation that stronglyreducespotentialintensityduringthe seasonsimmediatelyfollowingamajor eruption here too the differential vertical temperature response is key temperatures in the lower and middle troposphere cool while those near the tropopause rise aside from these deviations there is no substantial variation in thermodynamic properties over the 1000 yr simulation

a decadally resolved paleohurricane record archived in the late holocene sediments of a florida sinkhole article i nfo a 4500 year record of hurricane induced storm surges is developed from sediment cores collected from a coastal sinkhole near apalachee bay florida recent deposition of sand layers in the upper sediments of the pond was found to be contemporaneous with significant historic storm surges at the site modeled using slosh and the best track post 1851 a d dataset using the historic portion of the record for calibration paleohurricane deposits were identified by sand content and dated using radiocarbon based age models marine indicative foraminifera some originating at least 5 km offshore were present in several modern and ancient storm deposits the presence and long term preservation of offshore foraminifera suggest that this site and others like it may yield promising microfossil based paleohurricane reconstructions in the future due to the sub decadal 7 years resolution of the record and the site s high susceptibility to hurricane generated storm surges the average local frequency of recorded events approximately 3 9 storms per century is greater than that of previously published paleohurricane records from the region the high incidence of recorded events permitted a time series of local hurricane frequency during the last five millennia to be constructed variability in the frequency of the largest storm layers was found to be greater than what would likely occur by chance alone with intervals of both anomalously high and low storm frequency identified however the rate at which smaller layers were deposited was relatively constant over the last five millennia this may suggest that significant variability in hurricane frequency has occurred only in the highest magnitude events the frequency of high magnitude events peaked near 6 storms per century between 2800 and 2300 years ago high magnitude events were relatively rare with about 0 3 storms per century occurring between 1900 and 1600 years ago and between 400 and 150 years ago a marked decline in the number of large storm deposits which began around 600 years ago has persisted through present with below average frequency over the last 150 years when compared to the preceding five millennia

density cascading off shelf sediment transport evidence and implications bahama banks abstract suspended sediment concentrations in shelf waters are often appreciable but sediments on their own rarely contribute enough density to cause suspension currents to transport them offshelf however sediment charged hyperpycnal high density waters are often generated over continental shelves because of the same set of air sea interactions intense heat and moisture flux responsible for thermohaline production and circulation of deep ocean water masses we propose the term density cascading to describe the processes by which hyperpycnal waters are released from shelf areas and together with entrained sediments sink to their compensation level in the adjacent ocean density cascading probably involves a range of physical processes from pelagic draping of slopes and basins with shelf muds to initiating turbidity currents capable of scouring canyons and plunge pools sediment bypassing of slopes and deposition of sands in deep basins thermodynamic air sea interactions can generate hyperpycnal water at all latitudes therefore density cascading has important implications not only to the sedimentology of modern carbonate platforms such as the florida shelf and bahama banks and stratigraphy in ancient limestones but also to offshelf sediment flux in siliciclastic environments

late holocene climatic changes in west africa a high resolution diatom record from equatorial cameroon abstract holocene climatic changes in west africa are usually explained by increased decreased activity of the monsoon from the guinean gulf toward the continent according to a diatom record from lake ossa 3 50 n 9 36 e we suggest that in the near coastal areas of cameroon phases of intensification of the monsoon were marked by reduced precipitation and reduced evaporation conditions nowadays prevailing south of the equator 4 5 s during the austral winter lake ossa is a shallow lake located in one of the rainiest area of the african rain forest belt during the wet season march november it is fed by acid meteoric waters entailing low ph in the lacustrine waters during the dry season december february groundwater discharges allow the persistence of acid waters near the borders of the lake but in the inner parts the waters tend to be alkaline alkaliphilous diatoms are abundant in the surface sediment samples and are used as indicators of low precipitation at that time atmospheric dust containing reworked diatoms from saharan quaternary deposits is transported by the northern trade winds and reaches the ossa area wind blown diatoms are considered as a signature of the northern trade winds a diatom record from the western deep part of lake ossa has provided climatic data for the mid late holocene at a resolution of 50 60 years a major climatic change at 2700 cal yr bp was marked by the appearance of wind blown diatoms a millennial scale alternation between low and high precipitation episodes is recorded during the last 5500 years the low precipitation episodes before 2700 cal yr bp are interpreted as a consequence of a northward extension of the climatic conditions that nowadays characterize the southern congo during the austral winter when the monsoon extends into west africa and reaches the northern sub tropical latitudes the effects of low precipitation on the water balance and on the rain forest were obliterated by an extremely low evaporation between 2700 and 1300 cal yr bp precipitation was high and the rain forest intensively disturbed in response to convective storms a low precipitation episode between 1300 and 600 cal yr bp is explained contrarily to the previous similar episodes by tropical rainfalls located farther south than today during a larger part of the year the modern climate settles at about 600 cal yr bp the climatic oscillations on a millennial time scale were apparently coincident with temperature changes in the northern and southern atlantic suggesting that the monsoon over west africa was essentially driven by interactions between both hemispheres this interpretation is in agreement with available data from other equatorial and sub tropical regions of west africa

southward migration of the intertropical convergence zone through the holocene titanium and iron concentration data from the anoxic cariaco basin off the venezuelan coast can be used to infer variations in the hydrological cycle over northern south america during the past 14 000 years with subdecadal resolution following a dry younger dryas a period of increased precipitation and riverine discharge occurred during the holocene thermal maximum since approximately 5400 years ago a trend toward drier conditions is evident from the data with high amplitude fluctuations and precipitation minima during the time interval 3800 to 2800 years ago and during the little ice age these regional changes in precipitation are best explained by shifts in the mean latitude of the atlantic intertropical convergence zone itcz potentially driven by pacific based climate variability the cariaco basin record exhibits strong correlations with climate records from distant regions including the high latitude northern hemisphere providing evidence for global teleconnections among regional climates

cutmarks made by stone tools on bones from olduvai gorge tanzania fossils from olduvai gorge tanzania show cutmarks which establish that hominids were using stone tools on animal tissues during the lower pleistocene in africa we identified cutmarks by elimination of other likely causes of the marks on the bone surfaces for example gnawing or chewing by carnivores or rodents and damage made by tools of excavators or preparators this was achieved by comparing the marks on the fossils with those produced by known causes on modern bones using scanning electron microscopy sem because the fossils occur as part of accumulations of animal remains in relatively undisturbed geological contexts we conclude that there is a functional association between the stone artefacts and bones at these sites rather than an accidental postmortem association1 2

what happens around a fire faunal processing sequences and spatial distribution at qesem cave 300 ka israel abstract the technological innovation involving the controlled use of fire represents a decisive change in human subsistence hearths and the spatial distribution patterns associated with them constitute a valuable element in deepening our knowledge on human behaviour and its evolution studies focused on hearths and on the use of fire in general are diverse and carried out through different perspectives thus hearths are studied for their meaning in terms of diet caloric and light capacity and spatial organisation as well as for their role as communication and socialization focal points the site of qesem cave israel shows evidence of the controlled use of fire as early as 400 ka judging by the burned bones from the lowest units of the stratigraphic sequence a particular superimposed central hearth that was repeatedly used as a focus for human activities ca 300 ka is the topic of this study this succession of hearths at the same location in the cave yields dense faunal and lithic remains as well as evidence for spatial differentiation between areas here we present faunal taphonomical data from this specific archaeological context which includes not only the hearth area approximately 4 m2 but also the surrounding areas approximately 11 m2 the most common prey species is the mesopotamian fallow deer dama cf mesopotamica which displays a wide age range and a biased anatomical profile including mainly marrow rich bones such as long limb bones these characteristics especially those regarding the relative abundance of infantile and young fallow deer lead us to propose that social hunting techniques were practised following a seasonal regime this paper provides data on human subsistence behaviour during the formation of the hearth and the archaeological unit around it comparing the two from a taphonomical perspective elements such as size length of bone fragments and intensity of burning are spatially plotted to show differential space division all these data are considered in the reconstruction of subsistence strategies and hominin behaviour in the acheulo yabrudian cultural complex in the levant

caribbean coral tracks atlantic multidecadal oscillation and past hurricane activity it is highly debated whether global warming contributed to the strong hurricane activity observed during the last decade the crux of the recent debate is the limited length of the reliable instrumental record that exacerbates the detection of possible long term changes in hurricane activity which naturally exhibits strong multidecadal variations that are associated with the atlantic multidecadal oscillation amo the amo itself a major mode of climate variability remains also poorly understood because of limited data here we present the first coral based proxy record 18o that clearly captures multidecadal variations in the amo and the hurricane activity our record obtained from a brain coral situated in the atlantic hurricane domain is equally sensitive to variations in sea surface temperature sst and seawater 18o with the latter being strongly linked to precipitation by this means amplifying large scale climate signals in coral 18o the sst and precipitation signals in the coral provide the longest thus far continuous proxy based record of hurricane activity that interestingly exhibits a long term increase over the last century as multidecadal sst variations in this region are closely related to the amo this study raises new possibilities to extend the limited observations and to gain new insights into the mechanisms underlying the amo and long term hurricane variations

new taphonomic data of the 1 myr hominin butchery at untermassfeld thuringia germany abstract untermassfeld has provided a butchered bone assemblage and a mode 1 lithic record demonstrating hominin presence at a site which was classically viewed as paleontological this archaeological record was found during fieldwork and surveying in fluvial river banks and low to medium energy channel erosion sediments paleomagnetism and biostratigraphy has yielded an age for this hominin occupation close to the onset of the jaramillo subchron ca 1 07 myr in this paper we present new taphonomic data of the cut marked and hammer related bone material corresponding mainly to large sized herd species i e bison but also from cervids eucladoceros giulii and cervus s l nestii vallonnetensis and megafaunal species i e stephanorhinus hundsheimensis and hippopotamus amphibius antiquus distribution of skeletal elements and bone surface features suggests that this bone assemblage consists of animal remains with different taphonomic origins the assemblage formed during at most two or three sediment laden floods transporting both lithic tools and remains of animals that died of natural causes or were killed by predators the new taphonomic results presented here are important to analyze hominin colonization and adaptation to european mid latitude environments at 1 myr in competition for meat resources with large carnivores i e pachycrocuta brevirostris and panthera onca gombaszoegensis

stalagmite stable isotope record of recent tropical cyclone events we present a 23 yr stalagmite record 1977 2000 of oxygen isotope variation associated with 11 tropical cyclones tcs from actun tunichil muknal cave in central belize high resolution microsampling yielded a record of monthly to weekly temporal resolution that contains abrupt decreases negative excursions in calcite 18 o values that correspond with recent tc rain events nearby a logistic discriminant model reliably identifi ed tc proxy signals using the measurable parameters 18 o and 13 c values and single point changes in 18 o value the logistic model cor rectly identifi ed 80 of excursions as tc events and incorrectly classifi ed only 1 of nearly 1200 nonstorm sampling points in addition to enabling high resolution tc frequency reconstruction this geologic proxy also provides information about the intensity of individual tcs a multiple regression predicted tc intensity r 2 0 465 p 0 034 using sampling frequency and excursion amplitude consistent with previous low resolution studies we found that the decadal average 18 o value was lower during the 1990s when several tcs produced rainfall in the area but higher during the 1980s when only one tc struck longer accurately dated high resolution speleo them stable isotope records may be a useful new tool for paleotempestology to clarify associa tions between highly variable tc activity and the dynamic range of quaternary climate