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Changeover from a glacial to an interglacial climate is considered as transitional between two stable modes. Palaeoceanographic reconstructions using the polar foraminifera Neogloboquadrina pachyderma highlight the retreat of the Polar Front during the last deglaciation in terms of both its decreasing abundance and stable oxygen isotope values (δ18O) in sediment cores. While conventional isotope analysis of pooled N. pachyderma and G. bulloides shells shows a warming trend concurrent with the retreating ice, new single-shell measurements reveal that this trend is composed of two isotopically different populations that are morphologically indistinguishable. Using modern time series as analogues for interpreting downcore data, glacial productivity in the mid-North Atlantic appears limited to a single maximum in late summer, followed by the melting of drifting icebergs and winter sea ice. Despite collapsing ice sheets and global warming during the deglaciation, a second “warm” population of N. pachyderma appears in a bimodal seasonal succession, separated by the subpolar G. bulloides. This represents a shift in the timing of the main plankton bloom from late to early summer in a “deglacial” intermediate mode that persisted from the glacial maximum until the start of the Holocene. When seawater temperatures exceeded the threshold values, first the “cold” (glacial) then the “warm” (deglacial) populations of N. pachyderma disappeared, whilst G. bulloides with a greater tolerance to higher temperatures persisted throughout the Holocene to the present day in the midlatitude North Atlantic. Single-specimen δ18O of polar N. pachyderma reveals a steeper rate of ocean warming during the last deglaciation than appears from conventional pooled δ18O average values.

Individual foraminifera analysis (IFA) holds promise to reconstruct seasonal to interannual oceanographic variability. Even though planktonic foraminifera are reliable recorders of environmental conditions on a population level, whether they also are on the level of individuals is unknown. Yet, one of the main assumptions underlying IFA is that each specimen records ocean conditions with negligible noise. Here we test this assumption using stable isotope data measured on groups of four shells of Neogloboquadrina pachyderma from a 16–19 d resolution sediment trap time series from the subpolar North Atlantic. We find a within-sample variability of 0.11 ‰ and 0.10 ‰ for δ18O and δ13C respectively that shows no seasonal pattern and exceeds water column variability in spring when conditions are homogeneous down to hundreds of metres. We assess the possible effect of life cycle characteristics and delay due to settling on foraminifera δ18O variability with simulations using temperature and δ18Oseawater as input. These simulations indicate that the observed δ18O variability can only partially be explained by environmental variability. Individual N. pachyderma are thus imperfect recorders of temperature and δ18Oseawater. Based on these simulations, we estimate the excess noise on δ18O to be 0.11±0.06 ‰. The origin and nature of the recording imprecision require further work, but our analyses highlight the need to take such excess noise into account when interpreting the geochemical variability among individual foraminifera.

Deciphering the evolution of marine plankton is typically based on the study of microfossil groups. Cryptic speciation is common in these groups, and large intragenomic variations occur in ribosomal RNA genes of many morphospecies. In this study, we correlated the distribution of ribosomal amplicon sequence variants (ASVs) with paleoceanographic changes by analyzing the high-throughput sequence data assigned to Neogloboquadrina pachyderma in a 140,000-year-old sediment core from the Arctic Ocean. The sedimentary ancient DNA demonstrated the occurrence of various N. pachyderma ASVs whose occurrence and dominance varied through time. Most remarkable was the striking appearance of ASV18, which was nearly absent in older sediments but became dominant during the last glacial maximum and continues to persist today. Although the molecular ecology of planktonic foraminifera is still poorly known, the analysis of their intragenomic variations through time has the potential to provide new insight into the evolution of marine biodiversity and may lead to the development of new and important paleoceanographic proxies.

Introduction: Pachydermoperiostosis (PDP) or hypertrophic osteoarthropathy (HOA) is a rare disease that has genetic predisposition and defined clinical features. Aim of the work: To study and analyse the clinical features of Tunisian PDP patients and review the literature. Patients and methods: The PDP cases attending the Rheumatology Department of the University Hospital Farhat Hached of Sousse in Tunisia were retrospectively studied over a period of 17 years (2000–2017). Secondary causes were excluded. Results: The PDP cases had a primary and complete form of the disease and included 6 men at a frequency of 0.03% (6/20,000) of the total number of rheumatic diseases cases attending the rheumatology clinic. The mean age was 27 ± 12.3 years [18–46 years]. Five patients had arthralgia and one polyarthritis. Thickening of the skin of the head and distal extremities (pachyderma) and deep folds and furrows of the skin of the forehead was observed in all cases. Digital clubbing of the fingers and toes and spade-like enlargement of the hands and feet was noted in 5 cases. Hyperhidrosis of the hands and feet was observed in 4 cases and seborrhea in 2. Elevated acute phase reactants were found in 4 cases. Hypergammaglobulinemia was present in one case. Periostosis of the long bones was observed in all cases. Treatment consisted of analgesics in all cases, non-steroidal anti-inflammatory drugs in 2 cases and tamoxifen in 2 cases. Conclusions: Complete form of primary PDP is rarely present among rheumatic diseases patients in Tunisia. A multicenter larger number longitudinal study is recommended. Keywords: Pachydermoperiostosis, Clubbing, Hypertrophic osteoarthropathy, Periostosis

Pachydermoperiostosis (Touraine-Solente-Gole Syndrome) is a hereditary disorder which usually presents with bony lesions (periostosis), digital clubbing and skin thickening (pachyderma). Facial coarsening, spade-like hands and feet with increased sweating may cause diagnostic confusion between

Background Pachydermoperiostosis (PDP) is a rare disorder characterized by clubbing of the fingers, thickening of the skin (pachyderma), and excessive sweating (hyperhidrosis). It typically appears during childhood or adolescence, often around the time of puberty, and progresses slowly. Clinical presentations of PDP can be confused with secondary hypertrophic osteoarthropathy, psoriatic arthritis, rheumatoid arthritis, thyroid acropachy, and acromegaly. Case presentation A Mongolian male, aged 19 years, resident of a hilly district of Nepal, with history of consanguinity, presented to our outpatient department with chief complaints of pain and swelling in both hands and feet for 6 years. The pain was insidious in onset, throbbing in nature, and not relieved by over-the-counter medications. The patient also complained of profuse sweating, progressive enlargement of hands and feet, and gradual coarsening of facial features. On examination there were marked skin folds in the forehead, face, and eyelids. Clubbing and swelling of bilateral knee joints and ankle joints was also evident. He was subsequently investigated extensively for acromegaly. Insulin-like growth factor-1 level and oral glucose tolerance test were normal. Radiography of various bones showed periosteal hypertrophy with subperiosteal bone formation. Conclusions PDP should be considered as a differential diagnosis when a patient presents with hypertrophic osteoarthropathy and acromegalic features.

International audience; Eight SSU rDNA genetic types have been described in the planktonic foraminifera Neogloboquadrina pachyderma, but the level of correlation between genetic diversity and morphological variation remains unknown in this morphospecies. In this study, we combine molecular and morphometric analyses of specimens of N. pachyderma sampled during two consecutive years across a latitudinal gradient in the Indian sector of the Southern Ocean. We observe that three genetic types of N. pachyderma inhabit the (sub-)polar waters of the southern Indian Ocean where they have equivalent regional distributions to those previously observed in the South Atlantic. The geographic ranges of these genetic types are largely overlapping. Our morphometric data show that contrary to other planktonic foraminiferal morphospecies, there is no relationship between genetic diversity and morpho- logical di␣erentiation in at least two of the austral representatives of N. pachyderma (Type III and Type IV) despite a high morphological variability and large genetic distance between these types. These genetic types of N. pachyderma in the southern Indian Ocean thus constitute true cryptic species of planktonic foraminifera.

The paper illustrates and describes 15 species of planktonic foraminifera from the St. Erth Beds, Cornwall, S.W. England. The overlap of the stratigraphic ranges of Globorotalia inflata (d’Orbigny), G. praehirsuta Blow, G. tosaensis Takayanagi & Saito, Pulleniatina primalis Banner & Blow, Neogloboquadrina humerosa (Takayanagi & Saito) and dextrally coiled N. pachyderma (Ehrenberg) places the age of the fauna in the Globorotalia inflata Zone, Late Pliocene. The absence of Globorotalia puncticulata (Deshayes), G. truncatulinoides (d’Orbigny) and Neogloboquadrina atlantica (Berggren) confirms this age assignment and with the presence of G. inflata (d’Orbigny), the deposition of St. Erth beds can now be accurately placed at between 2.1 and 1.9 Ma. For this paper, it has been acceped that the Pliocene-Pleistocene boundary is marked by the first evolutionary appearance of G. truncatulinoides at about 1.9 Ma.

Relative abundance variations of planktonic Foraminifera have been studied for the Late Miocene to Early Pliocene time interval of 7.0 to 3.5 Ma from three sites in the North East Atlantic; DSDP607 (41°N), DSDP609 (50°N) and DSDP611 (53°N), Particular attention has been given to the percentage of benthic Foraminifera of total (benthic + planktonic) Foraminifera as an index of dissolution by aggressive bottom waters, and to the percentage of dextral Neogloboquadrina pachyderma of total (dextral + sinistral) N. pachyderma as an index of “Sub-Polar” or warmer waters.Strong dissolution, probably associated with the northward penetration of aggressive Antarctic Bottom Water, is observed at two of the sites up to and during the initiation of the Messinian “Salinity Crisis” in the adjoining Mediterranean Sea at about 5.8 Ma. All three sites exhibit strong cyclic fluctuations of the percentage of dextral N. pachyderma during the Messinian “Salinity Crisis” interval, from approximately 5.8 Ma to 4.8 Ma. These are interpreted as indicating wide-ranging oscillations of a water mass boundary, analogous to the present-day Polar Front, in the North Atlantic during the “Salinity Crisis”. Following the re-filling of the Mediterranean with normal marine waters at about 4.8 Ma, the dextral form of N. pachyderma, which is more characteristic of warmer waters than the sinistral form, becomes the dominant form and shows less quantitative variation at all three sites throughout the Early Pliocene.

Planktonic foraminiferal faunas have been studied from the Pleistocene of ODP Site 1073 (Leg 174A), New Jersey margin, NW Atlantic Ocean and their abundances have been compared in the >63 μm and >150 μm size-fractions from the same samples. Trends in the relative abundance of many species are similar in the two size-fractions, although the general level varies considerably. The mean abundance and ranges of Neogloboquadrina pachyderma (sinistral), N. pachyderma (dextral), Globorotalia inflata and Globigerina bulloides are greater in the >150 μm size-fraction compared with the >63 μm size-fraction. Turborotalita quinqueloba, Globigerinita uvula, G. glutinata, G. clarkei, and juvenile species are more abundant in the >63 μm size-fraction than the >150 μm size-fraction. Peaks (c. 60%) in abundance of G. uvula occur in the >63 μm size-fraction only, although the causes of these patterns are unclear. The data suggest that, in general, consistent palaeoclimatic/palaeoceanographic information is achieved by studying planktonic foraminiferal faunas from either size-fraction. However, because particular smaller species are either under-represented or even absent from the larger (>150 μm) size-fraction, the smaller (>63 μm) size-fraction must be included in studies of planktonic foraminifera. Furthermore, studies that involve planktonic foraminifera in the >63 μm size-fraction could provide different transfer function estimates for sea surface temperatures in areas where workers have only used larger (>125 μm and >150 μm) size-fractions.

International audience; Planktic foraminifers can be sensitive indicators of the changing environment including both the Arctic Ocean and Southern Ocean. Due to variability in their ecology, biology, test characteristics, and fossil preservation in marine sediments, they serve as valuable archives in paleoceanography and climate geochemistry over the geologic time scale. Foraminifers are sensitive to, and can therefore provide proxy data on ambient water temperature, salinity, carbonate chemistry, and trophic conditions through shifts in assemblage (species) composition and the shell chemistry of individual specimens. Production and dissolution of the calcareous shell, as well as growth and remineralization of the cytoplasm, affect the carbonate counter pump and to a lesser extent the soft-tissue pump, at varying regional and temporal scales. Diversity of planktic foraminifers in polar waters is low in comparison to lower latitudes and is limited to three native species: Neogloboquadrina pachyderma, Turborotalita quinqueloba, and Globigerina bulloides, of which N. pachyderma is best adapted to polar conditions in the surface ocean. Neogloboquadrina pachyderma hibernates in brine channels in the lower layers of the Antarctic sea ice, a strategy that is presently undescribed in the Arctic. In open Antarctic and Arctic surface waters T. quinqueloba and G. bulloides increase in abundance at lower polar to subpolar latitudes and Globigerinita uvula, Turborotalita humilis, Globigerinita glutinata, Globorotalia inflata, and Globorotalia crassaformis complement the assemblages. Over the past two to three decades there has been a marked increase in the abundance of Orcadia riedeli and G. uvula in the subpolar and polar Indian Ocean, as well as in the northern North Atlantic. This paper presents a review of the knowledge of polar and subpolar planktic foraminifers. Particular emphasis is placed on the response of foraminifers to modern warming and ocean acidification at high latitudes and the implications for data interpretation in paleoceanography and paleoclimate research.

To describe the horizontal and vertical distribution of recent planktic foraminifera in Fram Strait (Arctic), plankton samples were collected in the early summer of 2011 using a MultiNet sampler (>63 µm) at 10 stations along a west–east transect at 78°50′N. Five depth intervals were sampled from the sea surface down to 500 m. Additionally, sediment surface samples from the same locations were analysed. The ratio between absolute abundances of planktic foraminifera in the open ocean, at the ice margin and in the ice-covered ocean was found to be approximately 2:4:1. The assemblage was dominated by the polar Neogloboquadrina pachyderma (sin.) and the subpolar Turborotalita quinqueloba , which accounted for 76 and 15% of all tests in the warm, saline Atlantic waters and 90 and 5% in the cold and fresh Polar waters, respectively. Both species had maximum absolute abundances between 0 and 100 m water depth, however, they apparently lived shallower under the ice cover than under ice-free conditions. This indicates that the depth habitat of planktic foraminifera in the study area is predominantly controlled by food availability and not by temperature. The distribution pattern obtained by plankton tows was clearly reflected on the sediment surface and we conclude that the assemblage on the sediment surface can be used as an indicator for modern planktic foraminiferal fauna. Keywords : Planktic foraminifera; Fram Strait; Arctic Ocean; depth habitat; N. pachyderma (sin.); T. quinqueloba . (Published: 27 May 2014) To access the supplementary material for this article, please see Supplementary files in the column to the right (under Article Tools). Citation: Polar Research 2014, 33 , 22483, http://dx.doi.org/10.3402/polar.v33.22483

Touraine Solente Gole syndrome is a rare hereditary syndrome of primary pachydermoperiostosis, with the characteristic triad of pachydermia (or elephant like skin), periostosis and acropachia. A 27-year-old patient presented with aesthetic deformity of forehead due to deep skin folds and coarsening of facial features due to progressive thickening of skin. Associated palmoplantar hyperkeratosis with broadened of finger and toe tips and digital clubbing were noticed. Dermatologic evaluation revealed cutis verticis gyrata of scalp, seborrhoeic hyperplasia of face and hyperhidrosis. Natural history of the disease and aetiopathogenesis were reviewed. Aesthetic correction of forehead through frontal rhytidectomy was attempted.

The present study investigated the effects of ocean acidification and temperature increase on Neogloboquadrina pachyderma (sinistral), the dominant planktonic foraminifer in the Arctic Ocean. Due to the naturally low concentration of CO 3 2− in the Arctic, this foraminifer could be particularly sensitive to the forecast changes in seawater carbonate chemistry. To assess potential responses to ocean acidification and climate change, perturbation experiments were performed on juvenile and adult specimens by manipulating seawater to mimic the present-day carbon dioxide level and a future ocean acidification scenario (end of the century) under controlled (in situ) and elevated temperatures (1 and 4 °C, respectively). Foraminifera mortality was unaffected under all the different experiment treatments. Under low pH, N. pachyderma (s) shell net calcification rates decreased. This decrease was higher (30 %) in the juvenile specimens than decrease observed in the adults (21 %) ones. However, decrease in net calcification was moderated when both, pH decreased and temperature increased simultaneously. When only temperature increased, a net calcification rate for both life stages was not affected. These results show that forecast changes in seawater chemistry would impact calcite production in N. pachyderma (s), possibly leading to a reduction of calcite flux contribution and consequently a decrease in biologic pump efficiency.

金沢大学大学院自然科学研究科, Modern planktic foraminifera in 51 surface sediments from the Japan Sea, a marginal sea of the western North Pacific, were studied to reveal the relationships between geographical distribution and surface water masses in the Japan Sea. Twenty-four species belonging to 10 genera were identified, of which nine species, namely Neogloboquadrina incompta, Neogloboquadrina pachyderma, Globigerina quinqueloba, Globigerina bulloides, Globigerinoides ruber, Neogloboquadrina dutertrei, Pulleniatina obliquiloculata, Globigerinoides tenellus, and Globigerinita glutinata are predominant. We recognized four geographical distribution patterns of these dominant species that are related to hydrographic conditions in the Japan Sea. The transitional water formed by the mixture between the warm Tsushima Current and cold waters in the Japan Sea is optimal for N. incompta, while the distribution of N. pachyderma is matched with cold water in the northern Japan Sea. Globigerina quinqueloba and G. bulloides appear to be associated with less saline, nutrient-rich river water from the Changjiang (Yangtze River), and G. ruber, N. dutertrei, P. obliquiloculata, G. tenellus, and G. glutinata can be regarded as indicators of Tsushima Current Water. © by the Palaeontological Society of Japan.

Specimens of the planktic foraminiferal morphospecies, Globigerina bulloides, Turborotalita quinqueloba, Neogloboquadrina pachyderma (dextral) and Globigerinita uvula, were collected along a subarctic Atlantic transect. Partial sequences of the small subunit (SSU) ribosomal (r) RNA gene were obtained and a distance-based foraminiferal phylogeny constructed. The low latitude morphospecies, Globigerina falconensis, was included to improve within cluster resolution. G. bulloides, G. falconensis and T. quinqueloba cluster together as a distinct group within the molecular phylogeny. The diversification of these three morphospecies from their common ancestor is clearly later than the main planktic spinose radiation, consistent with current interpretations of the fossil record. G. bulloides and G. falconensis are highly divergent from one another, supporting palaeontological and biological evidence that they are separate species. N. pachyderma (dextral) clusters with Neogloboquadrina dutertrei within the benthic and non-spinose planktic region of the tree. G. uvula also clusters within the benthic and non-spinose planktic region of the tree, adjacent to Globigerinita glutinata, a member of the same genus, though resolution is too low to provide evidence of a sister-taxon relationship. The Globigerina bulloides and Turborotalita quinqueloba morphospecies comprise a complex of distinct SSU rDNA genetic types. These fall into two groups, representing high and low latitude genotypes. Along the subarctic transect, G. bulloides and T. quinqueloba were each represented by two distinct genotypes. Neogloboquadrina pachyderma (dextral) and Globigerinita uvula were each represented by a single genotype. Genotypes of a morphospecies exhibit distinctive and different distribution patterns. In the case of Globigerina bulloides, the genotype distribution is suggestive of differing adaptation. However, the Turborotalita quinqueloba genotype distribution was complicated by their co-existence in the same water column throughout the eastern sector. Further investigation will be required to determine whether they occupy a different niche within the water column. Although only T. quinqueloba Type IIa was found in the western region, sampling density was low and inconclusive. The Neogloboquadrina pachyderma (dextral) genotype was found across the entire transect. Further investigation of genotype distribution and genotype/habitat relationships could provide new high-resolution proxies for past oceanographic/climate reconstructions. © 2001 Elsevier Science B.V. All rights reserved.

Given the importance of high-latitude areas in the ocean-climate system, there is need for a paleothermometer that is reliable at low temperatures. Here we assess the applicability of the Mg/Ca-temperature proxy in colder waters (5-10 degrees C) by comparing for the first time the seasonal Mg/Ca and delta O-18 cycles of N. pachyderma (s) and G. bulloides using a sediment trap time-series from the northern North Atlantic. While both species show indistinguishable seasonal delta O-18 patterns that clearly track the near surface temperature cycle, their Mg/Ca are very different. G. bulloides Mg/Ca is high (2.0-3.1 mmol/mol), but varies in concert with the seasonal temperature cycle. The Mg/Ca of N. pachyderma (s), on the other hand, is low (1.1-1.5 mmol/mol) and shows only a very weak seasonal cycle. The delta O-18 patterns indicate that both species calcify in the same depth zone. Consequently, depth habitat differences cannot explain the contrasting Mg/Ca patterns. The elevated Mg/Ca in pristine G. bulloides might be due to the presence of high Mg phases that are not preserved in fossil shells. The contrasting absence of a seasonal trend in the Mg/Ca of N. pachyderma (s) confirms other studies where calcification temperatures were less well constrained. The reason for this absence is not fully known, but may include species-specific vital effects. The very different seasonal patterns of both species' Mg/Ca underscore the importance of parameters other than temperature in controlling planktonic foraminiferal Mg/Ca. Our results therefore lend further caution in the interpretation of Mg/Ca-temperature reconstructions from high northern latitudes.

We present a new planktonic foraminifera model developed for the global ocean mixed-layer. The main purpose of the model is to explore the response of planktonic foraminifera to different boundary conditions in the geological past, and to quantify the seasonal bias in foraminifera-based paleoceanographic proxy records. This model is forced with hydrographic data and with biological information taken from an ecosystem model to predict monthly concentrations of the most common planktonic foraminifera species used in paleoceanography: N. pachyderma (sinistral and dextral varieties), G. bulloides, G. ruber (white variety) and G. sacculifer. The sensitivity of each species with respect to temperature (optimal temperature and range of tolerance) is derived from previous sediment-trap studies. Overall, the spatial distribution patterns of most of the species are in agreement with core-top data. N. pachyderma (sin.) is limited to polar regions, N. pachyderma (dex.) and G. bulloides are the most common species in high productivity zones, while G. ruber and G. sacculifer are more abundant in tropical and subtropical oligotrophic waters. For N. pachyderma (sin) and N. pachyderma (dex.), the season of maximum production coincides with that observed in sediment-trap records. Model and sediment-trap data for G. ruber and G. sacculifer show, in general, lower concentrations and less seasonal variability at all sites. A sensitivity experiment suggest that, within the temperature-tolerance range of a species, food availability may be the main parameter controlling its abundance.

Planktonic foraminifera with trochospirally arranged chambers can produce shells with two different coiling directions. Some morphospecies show a strong preference for either right-handed (dextral) or left-handed (sinistral) coiling, while other morphospecies appear in mixed coiling proportions varying around a midpoint value. Some display a pattern of distinct shifts in their coiling ratios spatially and through time. Although the underlying mechanisms controlling coiling direction are not understood, many workers have assumed it to be a morphological feature reflecting ecophenotypic variation and have used coiling ratios extensively for paleoenvironmental reconstruction. Recent genetic studies now clearly demonstrate that coiling direction in planktonic foraminifera is a genetic trait, heritable through time and not environmentally controlled. Previously reported links between coiling and environmental factors result from the different ecological preferences of the genetically distinct coiling types. Neogloboquadrina pachyderma is the most important provider of paleoproxies on the state and variation of high latitude oceans in the Quaternary. It has two distinct coiling forms with virtually exclusive distributions that appear to be controlled by water temperature. The genetic evidence shows that the two opposite coiling morphotypes diverged many millions of years ago and they have distinctly different ecologies. In combination with fossil evidence, biogeography and ecology, the degree of genetic distinction between the two coiling types of N. pachyderma strongly implies that they should be considered different species. The genetic evidence also demonstrates a low level (< 3%) aberrant coiling associated with each morphotype posing a serious nomenclature problem for taxonomists and paleoceanographers alike. The presence of aberrant coiling and the continual need for paleoceanographers to refer to coiling direction in the literature demands the re-classification of the right coiling N. pachyderma genotypes as a distinct species to simplify nomenclature and reference. We propose the adoption of the widely recognized name incompta for the dextral morphospecies. Anuar io do Inst i tu to de Geociencias UFRJ ISSN 0101-9759 Vol. 29 1 / 2006 p. 186

19 pages, 5 figures, 4 tables.-- Printed version published Nov 30, 2004., Detailed analysis of the planktonic foraminifera assemblages of ODP Site 977, situated in the Alboran Sea (36°1,9′N; 1°57,3′W), led us to recognize 42 planktonic foraminiferal events that occurred during marine isotope stages (MIS) 4 and 5. These events were defined by changes in the abundances of Neogloboquadrina pachyderma (right and left coiling), Turborotalita quinqueloba, Globorotalia scitula, Globorotalia inflata, Globigerina bulloides and Globigerinoides ruber (white and pink varieties). Foraminiferal assemblages changed in response to glacial–interglacial and millennial climate variability throughout the last 150 ka. Based on the estimation of sea surface temperatures (SST) using the modern analog technique and the oxygen isotope data measured in G. bulloides, we inferred the oxygen isotopic composition of sea water (δw). SST increased in the Alboran Sea during the main Dansgaard–Oeschger Interstadials, such as interstadial 19 to 24. Even though N. pachyderma (left coiling) is very scarce before Heinrich Event (HE) 6, three cold pulses can be identified, between 65 and 85 ka ago. Moreover, increases in abundance of T. quinqueloba and G. scitula are recorded during D–O Stadials 20 and 21., The maximum temperature, which was attained during the Last Interglacial, was about 2 °C higher than recent temperature and that reached over the Holocene. Planktic foraminifera assemblages and paleotemperatures remained cold 3 ka after the beginning of Termination II (T-II), 130 ka ago, probably in connection with the occurrence of Heinrich event 11 in the North Atlantic., The abundance of G. bulloides during the deposition of organic rich layers (ORLs) of MIS 5, accompanied by lower isotope values in surface waters (δw), could indicate the presence of a fresher surface layer associated with an increase in marine surface productivity., This work was funded by DGCYT projects PB-98-0288, FEDER 1FD1997-1148 (CLI) and BTE2002-04670, and by the Spanish Government FPI Grant FP96 11964731.

Planktonic foraminiferal records from Site 1083 (ODP Leg 175) were used to investigate changes in surface water conditions in the Northern Benguela Region over the past 450 ky. The assemblages of planktonic foraminifera are dominated by four species: sinistral coiling Neogloboquadrina pachyderma, dextral coiling N. pachyderma, Globigerina bulloides and Globorotalia inflata. Besides, tropical species deliver a small contribution to the assemblage. The most prominent temporal variations, displayed by N. pachyderma (s+d), represent changes in the coastal upwelling and the presence of cold, nutrient rich waters over the core site. Neogloboquadrina pachyderma (s+d) shows cyclic variability in the eccentricity and, to a less extent, precession frequencies. The changes indicate increased upwelling intensity in glacial maxima and precession maxima, and correlate well with the wind-strength record of Stuut et al. (2002). During glacial maxima, steep temperature gradients over the Southern Hemisphere caused strong SE trade winds and strong upwelling. Precession maxima cause a weak monsoonal circulation, more zonal SE trade winds, strong coastal upwelling, and nutrient-rich surface waters over ODP Site 1083. Advection of Angola Current (AC) surface water into the Walvis Basin, indicated by the tropical species, occurs when the Angola Benguela Front (ABF) is positioned southward. Occasionally, this happened during glacial maxima, as can be explained with the reconstructed and predicted meridional movements of the ABF. The amount of AC water was never sufficient to suppress the marine biological production at the core site. The contribution of Benguela Current (BC) water, reflected by Globorotalia inflata, is greatly determined by the upwelling. In periods of strong upwelling, the BC influence is suppressed. In several glacial substages, the temperature of the upwelling South Atlantic Central Water (SACW) may have been increased, as suggested by the dominance of Neogloboquadrina pachyderma (d) in the upwelling record. This phenomenon may be due to intensified subduction in the central South Atlantic that induces the formation of SACW, or to larger contributions of Eastern SACW to the upwelling water. Around 250-200 ky BP, a long-term shift to higher productivity occurred that is absent in the upwelling record. It was accompanied with a transition from a precession and obliquity variability to an eccentricity dominated variability in the Globorotalia inflata (BC) record. The shift was probably connected to a long-term southward shift of the circumpolar oceanic frontal systems south of the African continent.

The shells of the planktonic foraminifer Neogloboquadrina pachyderma have become a classical tool for reconstructing glacial–interglacial climate conditions in the North Atlantic Ocean1, 2, 3. Palaeoceanographers utilize its left- and right-coiling variants, which exhibit a distinctive reciprocal temperature and water mass related shift in faunal abundance both at present and in late Quaternary sediments1, 2, 4, 5. Recently discovered cryptic genetic diversity in planktonic foraminifers6, 7, 8 now poses significant questions for these studies. Here we report genetic evidence demonstrating that the apparent ‘single species’ shell-based records of right-coiling N. pachyderma used in palaeoceanographic reconstructions contain an alternation in species as environmental factors change. This is reflected in a species-dependent incremental shift in right-coiling N. pachyderma shell calcite δ18O between the Last Glacial Maximum and full Holocene conditions. Guided by the percentage dextral coiling ratio, our findings enhance the use of δ18O records of right-coiling N. pachyderma for future study. They also highlight the need to genetically investigate other important morphospecies to refine their accuracy and reliability as palaeoceanographic proxies.

22 pages, 6 figures, 4 tables.-- Printed version published May 2003.-- Supporting information available at: http://dx.doi.org/10.1016/S0377-8398(02)00160-3, Detailed study of associations of planktonic foraminifera in cores MD95-2043 and ODP 977, located in the Alboran Sea (Mediterranean Sea), has allowed the identification of 29 new faunal events, defined by abrupt changes in the abundances of Neogloboquadrina pachyderma (right and left coiling), Turborotalita quinqueloba, Globorotalia scitula, Globorotalia inflata, Globigerina bulloides and Globigerinoides ruber (white and pink varieties). The age model for ODP 977 was based on that of MD95-2043 [Cacho et al. (1999), Paleoceanogr. 14, 698–705], on the isotopic stratigraphy, and on two AMS 14C measurements. Sea Surface Temperatures (SSTs) were estimated for the last 54 kyr using the Modern Analog Technique (MAT) and were compared with the SSTs provided by the Uk′37 method. The Uk′37 record is very similar to the MAT annual mean temperature record for the last 8 kyr. However, for older times alkenone-derived temperatures are consistently higher than the annual MAT temperatures. This offset may be due to an underestimation of the SST provided by the planktonic foraminiferal method for glacial times, to an overestimation of the Uk′37 record, or to changes in the seasonal production of alkenones. Most of the variability in the fauna is related to the millennial variability of Heinrich and Dansgaard–Oeschger (D–O) events. During Heinrich events (HEs) and most of the other D–O stadials, G. bulloides, T. quinqueloba and G. scitula increased, while N. pachyderma (right coiling), G. inflata and G. ruber decreased. By contrast, N. pachyderma (left coiling) was only abundant in the HEs. The main component of the associations – N. pachyderma (right coiling) – follows a general trend similar to that of sea-level and δ18O. This species reached its highest abundance during the Last Glacial Maximum, when sea-level was at a lower position. The occurrence of a shallower nutricline owing to a shallowing of the interface between Atlantic inflowing and Mediterranean outflowing waters could have favoured the development of neogloboquadrinids in the vicinity of the Strait of Gibraltar., This work was funded by DGCYT projects PB-98-0288, FEDER 1FD1997-1148 (CLI), and BTE2002-04670, and by the Spanish Government FPI Grant FP96 11964731.

Cranio-Osteoarthropathy (COA) is a very rare form of primary hypertrophic osteoarthropathy (HOA). HOA is characterised by digital clubbing, arthropathy, pachyderma and sub-periosteal new bone formation along shafts of long bones. In COA, decreased neurocranium ossification is seen without the pachyderma feature.