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Raymond Casey was an internationally recognized expert in two entirely different fields—geology and philately. He achieved this despite leaving school at 14. By then he was already collecting and studying fossils from his home town, Folkestone, and in 1939, despite not having a degree, he obtained a post with the Geological Survey of Great Britain in the modest role of assistant to C. J. Stubblefield. After war-time service in the RAF, he returned to the Survey in a similar role, but spent much of his ‘spare time’ researching and publishing on Lower Cretaceous palaeontology and stratigraphy. His fortunes began to change when, at the age of 38, he was admitted to Reading University to study for a doctorate. His thesis on Lower Greensand stratigraphy and palaeontology was recognized as an outstanding study that led to major publications including a nine-part monograph of the ammonite faunas. Then, in the late 1950s, he also began to study faunas from Jurassic–Cretaceous boundary beds in eastern England as part of his official work and this led to him visiting the Soviet Union on several occasions from 1963 onward. On the first visit he met the academician Nalivkin in Leningrad, who, as well as being an eminent geologist, was a keen philatelist. This led to Raymond taking an enthusiastic interest in pre-revolutionary Russian postal history, which resulted in numerous publications and awards and, after his retirement, became his main focus of interest.

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Peter Robinson was born in York on 15 January 1936, grew up in Scarborough and attended the Graham Sea Training School. But rather than going to sea afterwards he took a series of local jobs while developing his lifelong interest in geology and natural history. By 1954 he had become a National Park Voluntary Warden, and in 1957 he joined both the Yorkshire Geological Society and the Botanical Society of the British Isles. He began his geological career in 1957 as a junior laboratory technician in the former Geology Department of Hull University. At that time, it was a very small department and, together with Mike Holiday, Peter provided the whole range of technical support required. There, together with then research student John Catt, he developed a new technique for preparing thin sections of clays. This was published in Geological Magazine in 1961. His helpfulness and enthusiasm were already apparent and remained characteristics of Peter throughout his life. His contribution to the department and university extended far beyond his technical role – he took the students’ Harker Geological Society on day excursions to the Yorkshire coast, and was always happy to help them with practical queries. He helped members of the botany department in the field, showing the link between geology and floral distributions in the North Yorks Moors, and he was already building up an important collection of local fossils that he continued to add to for the rest of his career. Peter was very generous …

Three distinct, rich neocomitid faunas occur in the Agrio Formation (middle Valanginian to lowermost Barremian). In the ammonite sequences between, neocomitids are very rare and limited to two thin horizons. The lower, upper Valanginian level has yielded Neocomites (Varlheideites) cf. peregrinus Rawson and Kemper, Neocomites (Varlheideites) sp. nov.? and Rodighieroites sp. which are widely distributed taxa. The upper level contains Comahueites aequalicostatus gen. et sp. nov., which appears endemic to the basin.

In the Burythorpe area of the Howardian Hills, located on the northern margin of the Market Weighton High, the Callovian succession is represented only by Lower Callovian sediments. These belong to the Kellaways Sand Member (Kellaways Formation), up to 12 m thick, but thinning southwards to 5 m. This contrasts with the more complete Callovian succession (Osgodby Formation) on the Yorkshire coast (Cleveland Basin) which is up to 32.5 m thick. At Burythorpe Quarry the Kellaways Sand Member has yielded palynomorphs and ammonites confirming an Early Callovian (Koenigi Zone) age with depositional hiatuses above and below. The sequence consists of a yellow-white, poorly cemented, fine-to medium grained, unimodal uncemented sand (moulding sand) with sparse grey clay beds and laminae, in marked contrast to the broadly coeval Red Cliff Rock Member (Osgodby Formation) of the Cleveland Basin. The depositional environment is interpreted as a tidally influenced shallow sea on the margin of the Market Weighton High, in a shallow sub-tidal regime, similar to the sub-tidal sand-mud lithofacies in the Heligoland region of the present-day North Sea. Winnowing of the sand in highly mobile substrate resulted in a unimodal grain size, lack of impurities, and sparse shelly- and ichnofaunas. However, during quieter water phases, grey clay laminae were deposited at the base of channels, allowing colonization of the substrate by burrowing ichnofauna and deposition of palynomorphs. Sparse, calcite-cemented tabular beds with a benthic shelly fauna, ammonites, Planolites burrows and mudstone rip-up clasts are interpreted as the deposits of periodic storm events. The marked local variation in thickness of the Kellaways Sand Member in the Howardian Hills is probably due to synsedimentary east–west-trending faulting related to the Flamborough Fault Zone.

A new CA-ID TIMS U–Pb age of 130.39 ± 0.16 Ma is presented here from the Pilmatué Member of the Agrio Formation, lower Hauterivian of the Neuquén Basin in west-central Argentina. This high precision radioisotopic new age, together with the two former ones from the upper Hauterivian Agua de la Mula Member of the Agrio Formation and modern cyclostratigraphic studies in the classical sections of the Mediterranean Province of the Tethys indicate that the Hauterivian Stage spans some 6 Ma, starting ca. 132 Ma and ending ca. 126 Ma. These radioisotopic ages are tied to ammonite biostratigraphy and calcareous nannofossil bioevents and biozones recognized in the Neuquén Basin which in turn are correlated with the Mediterranean standard zones. A new geological time scale for the Valanginian–Hauterivian stages in the Mediterranean region integrating astrochronological and radiochronological data differs with the current official geological time scale which still maintains poorly constraint absolute ages for the Berriasian-Aptian interval. Fil: Aguirre-Urreta, Maria Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos ; Argentina Fil: Schmitz, Mark. Boise State University; Estados Unidos Fil: Lescano, Marina Aurora. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos ; Argentina Fil: Tunik, Maisa Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; Argentina Fil: Rawson, Peter F.. University of Hull; Reino Unido. University College London; Reino Unido Fil: Concheyro, Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos ; Argentina Fil: Buhler, Mariano. YPF - Tecnología; Argentina Fil: Ramos, Victor Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos ; Argentina

Fil: Tunik, Maisa A. Universidad Nacional de Río Negro. Instituto de Investigación en Paleobiología y Geología. Río Negro; Argentina Fil: Tunik, Maisa A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigación en Paleobiología y Geología. Río Negro; Argentina Fil: Aguirre Urreta, Beatriz. Universidad de Buenos Aires. Instituto de Estudios Andinos Don Pablo Groeber. Buenos Aires; Argentina. Fil: Aguirre Urreta, Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios Andinos Don Pablo Groeber. Buenos Aires; Argentina. Fil: Martinez, Mathieu. Universität Bremen. MARUM – Center for Marine Environmental Sciences. Bremen; Germany. Fil: Schmitz, Mark. Boise State University. Department of Geosciences. Idaho; USA. Fil: Lescano, Marina. Universidad Nacional de Río Negro. Instituto de Investigación en Paleobiología y Geología. Río Negro; Argentina Fil: Lescano, Marina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigación en Paleobiología y Geología. Río Negro; Argentina Fil: Omarini, Julieta. Universidad Nacional de Río Negro. Instituto de Investigación en Paleobiología y Geología. Río Negro; Argentina Fil: Omarini, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigación en Paleobiología y Geología. Río Negro; Argentina Fil: Kuhnert, Henning. Universität Bremen. MARUM – Center for Marine Environmental Sciences. Bremen; Germany. Fil: Concheyro, Andrea. Universidad de Buenos Aires. Instituto de Estudios Andinos Don Pablo Groeber. Buenos Aires; Argentina. Fil: Concheyro, Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios Andinos Don Pablo Groeber. Buenos Aires; Argentina. Fil: Rawson, Peter F. University of Hull. School of Environmental Sciences. Hull; UK. Fil: Rawson, Peter F. University College London. Department of Earth Sciences. London; UK. Fil: Ramos, Victor A. Universidad de Buenos Aires. Instituto de Estudios Andinos Don Pablo Groeber. Buenos Aires; Argentina. Fil: Ramos, Victor A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios Andinos Don Pablo Groeber. Buenos Aires; Argentina. Fil: Reboulet, Stéphane. Université de Lyon, UCBL, ENSL, CNRS, LGL TPE, Bâtiment Géode. Villeurbanne; France. Fil: Noclin, Nicolas. Université de Lyon, UCBL, ENSL, CNRS, LGL TPE, Bâtiment Géode. Villeurbanne; France. Fil: Frederichs, Thomas. Universität Bremen. MARUM – Center for Marine Environmental Sciences. Bremen; Germany. Fil: Nickl, Anna L. Universität Bremen. MARUM – Center for Marine Environmental Sciences. Bremen; Germany. Fil: Pälike, Heiko. Universität Bremen. MARUM – Center for Marine Environmental Sciences. Bremen; Germany. An integrated radio-astrochronological framework of the Agrio Formation in the Andean Neuquén Basin of westcentral Argentina provides new constraints on the age and the duration of the late Valanginian through Hauterivian stratigraphic interval. A CA-ID TIMS U-Pb age of 126.97 ± 0.04(0.07)[0.15] Ma is presented here from the upper Hauterivian Agua de la Mula Member of the Agrio Formation. Biostratigraphic data from ammonoids and calcareous nannofossils and this high precision new radioisotopic age, together with three former ones from the same Agrio Formation are combined with new astrochronological data in the Andes. These are correlated with modern cyclostratigraphic studies in the classical sections of the Mediterranean Province of the Tethys, supporting detailed interhemispheric correlations for the Early Cretaceous. We also provide new δ13C data from the Agrio Formation which are compared with records from the classic Tethyan sections. According to our calibration, the minimum in the values in the mid-Hauterivian appears to be synchronous and, thus, another important stratigraphic marker for global correlation. A new duration of 5.21 ± 0.08 myr is calculated for the Hauterivian Stage, starting at 131.29 ± 0.19 Ma and ending at 126.08 ± 0.19 Ma. The difference between the duration of the Hauterivian in GTS2016 and in this study is 1.32 myr while the base and top of the GTS2016 Hauterivian differ respectively by 3.40 and 4.69 myr.

Summary Betton Farm quarries contain, within a small area, a remarkable range of facies associated with the development of a Jurassic coral reef. A NW–SE-trending barrier reef protected the whole area containing the two quarries. Betton Farm North Quarry displays Thamnasteria patch reefs. These consist of scattered, 1 m high masses of colonial coral surrounded by reef debris that were situated behind the barrier within a large reef platform area. In Betton Farm South Quarry, bioclastic sand, consisting largely of coral and bivalve debris, interdigitates with the development of a small ribbon reef made up of the massive colonial coral Thamnasteria . This ribbon reef, only 3 to 4 m wide, sheltered a lagoonal area that accumulated lime mud and was colonized by large gastropods and burrowing bivalves. A fauna of reef-specializing bivalves and echinoids occupied these areas of patch/ribbon reef development, which were periodically swept by nutrient-bearing currents. Competition between the growth of the ribbon of Thamnasteria and the accumulation of fringing sediments saw periods when the Thamnasteria expanded over the coral-shell sand, and periods when the encroaching sediment cut back the growth of the Thamnasteria considerably. Considered initially to represent the Coral Rag Member of the Coralline Oolite Formation, the Betton Farm Coral Bed is now seen to represent localized coral reef developments situated near the base of the Malton Oolite Member, and growing upon antecedent bedrock features such as hard-ground surfaces that formed during pauses in sedimentation of the Malton Oolite.

The 5th meeting of the IUGS Lower Cretaceous Ammonite Working Group (the Kilian Group) held in Ankara, Turkey, 31st August 2013, discussed the Mediterranean ammonite zonation, and its calibration with different ammonite zonal schemes of the Boreal, Austral and Central Atlantic realms. Concerning the standard zonation, that corresponds to the zonal scheme of the West Mediterranean province, some changes have been made on two stages. For the Valanginian, the Busnardoites campylotoxus Zone was abandoned; the upper part of the lower Valanginian is now characterised by the Neocomites neocomiensiformis and Karakaschiceras inostranzewi zones. For the upper Barremian, the former Imerites giraudi Zone is here subdivided into two zones, a lower I. giraudi Zone and an upper Martellites sarasini Zone. The I. giraudi Zone is now subdivided into the I. giraudi and Heteroceras emerici subzones, previously considered as horizons. The current M. sarasini and Pseudocrioceras waagenoides subzones correspond to the lower and upper parts of the M. sarasini Zone, respectively. The Anglesites puzosianum Horizon is kept. The Berriasian, Hauterivian, Aptian and Albian zonal schemes have been discussed but no change was made. The upper Hauterivian zonal scheme of the Georgian (Caucasus) region (East Mediterranean province) has been compared with the standard zonation. Discussions and some attempts at correlations are presented here between the standard zonation and the zonal schemes of different

Procedures used to define an international chronostratigraphic stage boundary and to locate and ratify a Global Boundary Stratotype Section and Point (GSSP) are outlined. A majority of current GSSPs use biostratigraphic data as primary markers with no reference to any physico-chemical markers, despite the International Subcommission on Stratigraphic Classification (ISSC) suggestion that such markers should be included if possible. It is argued that such definitions will not produce the high-precision Phanerozoic time scale necessary to understand such phenomena as pre-Pleistocene ice ages and global climate change. It is strongly recommended that all GSSPs should have physico-chemical markers as an integral part of their guiding criteria, and where such markers cannot be found, the GSSP should be relocated. The methods and approach embodied in oceanic stratigraphy – coring, logging, analysing and archiving of drill sites by numerous experts using a wide range of methods – could usefully serve as a scientific model for the analysis and archiving of GSSPs, all of which are on the present-day continents. The incorporation of many more stratigraphic sections into GSSP studies, the application of physico-chemical methods, and the replacement of old U–Pb dates by newer CA-TIMS U–Pb dates, together with the use of constrained optimization (CONOP) programs that produce a calendar of events from many sections, should lead to much more precise timescales for pre-Cenozoic time than are currently available.

Two species of decapod crustacean are recordedfrom the Agua de la Mula Member of the Agrio Formation(Upper Hauterivian – Lower Barremian) of the Neuque´nBasin of west-central Argentina, namely Astacodes falcifer Belland a new species of Palaeohomarus, P. pacificus. The preser-vation of the specimens is exceptional, some showing delicatecompound eyes and a stridulatory apparatus, features rarelyfound in fossil forms. Many specimens are preserved articu-lated inside calcareous nodules, within dark-grey shales. Thelobster-bearing sediments accumulated in a low-energy mar-ine environment and diagenetic mineralization occurred veryrapidly, prior to significant decay, thus allowing exceptionalpreservation of specimens. Palaeohomarus was a rare genusin the Cretaceous with a palaeogeographic distributionrestricted to the Mediterranean Tethys, the eastern USA andMadagascar, while Astacodes falcifer has been recorded onlyfrom Speeton (eastern England) and Neuque´n. Key words: Crustacea, Lower Cretaceous, Argentina, excep-tional preservation, eyes, stridulatory structure.T

Although the Agrio Formation (Valanginian-Early Barremian) yields rich ammonite faunas at many levels, the highest beds are very sparsely fossiliferous. However, intensive collecting over the years has yielded a sparse fauna of heteromorph ammonites that are completely new to Argentina. Three taxa are represented, Sabaudiella riverorum sp. nov., Curacoites rotundus gen. et sp. nov. and Hamulinites? sp. The fauna is placed in a new ammonite zone of Sabaudiella riverorum and dated as latest Hauterivian-Early Barremian. Fil: Aguirre-Urreta, Maria Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Rawson, Peter F.. University of Hull; Reino Unido. University College London; Reino Unido

The ‘Tertiary’, omitted from IUGS-approved timescales since 1989, is still in common use. With the recent re-instatement of the Quaternary as a formal unit, the question arises as to whether the Tertiary too should be reinstated as a formal period, with the ‘Paleogene’ and ‘Neogene’ being downgraded to sub-periods. This paper presents arguments for and against this proposal, stemming from discussions by members of the Geological Society Stratigraphy Commission. It is intended to stimulate discussion of the topic in the wider community.

The Pseudofavrella angulatiformis Zone (upper Valanginian) of the Agrio Formation in the Neuquén Basin, Argentina, is characterized exclusively by a complex sequence of neocomitid faunas that are sandwiched between the olcostephanids of the underlying Viluceras permolestus Subzone beneath and the holcodiscid faunas of the Holcoptychites neuquensis Zone above (lowermost Hauterivian). Three successive neocomitid genera, Pseudofavrella, Chacantuceras and Decliveites gen. nov., characterize three subzones. Over half the taxa are new: Pseudofavrella robusta, P. sp. nov. 1 and 2, Chacantuceras casanuestraense, Chacantuceras coniunctum, Decliveites crassicostatus, and Decliveites agrioensis. Fil: Aguirre-Urreta, Maria Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Rawson, Peter F.. University College London; Reino Unido. University of Hull; Reino Unido

The first carbon and oxygen isotope curves for the Valanginian to Early Barremian (Early Cretaceous) interval obtained from outcrops in the Southern Hemisphere are presented. They were obtained from well-dated (by ammonites) sediments from the Neuquén Basin, Argentina. Measurements were acquired by the innovative method of analysing fossil oyster laminae. The occurrence of the well-established mid-Valanginian positive carbon isotope excursion is documented, while less well-marked positive events may also correlate with peaks identified in the well-known successions of SE France. The mid-Valanginian positive carbon isotope event in the Neuquén Basin is possibly associated with organic-rich sediments. A similar relationship is seen in the European Alps and in oceanic cores in some areas of the world. Fil: Aguirre-Urreta, Maria Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Price, Gregory D.. University of Plymouth; Reino Unido Fil: Ruffell, Alastair H.. The Queens University of Belfast; Irlanda Fil: Lazo, Dario Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Kalin, Robert M.. The Queens University of Belfast; Irlanda Fil: Ogle, Neil. The Queens University of Belfast; Irlanda Fil: Rawson, Peter F.. University of Hull; Reino Unido. Colegio Universitario de Londres; Reino Unido

Of the 16 ammonite families of Valanginian to Early Barremian age, six are represented in the Neuquen Basin–the Neocomitidae, Olcostephanidae, Oosterellidae, Holcodiscidae, Ancyloceratidae and Douvilleiceratidae. Normally, only one or two ammonite genera occur at any one level, and there were ten turnovers at family level. Each turnover marks an important immigration event and other immigrations sometimes occurred between. All the taxa are of Tethyan origin; but while some immigrants are Andean Province forms, other are taxa that for at least part of their temporal range achieved an almost pandemic distribution, even invading the marginal Boreal basins of NW Europe (North Sea and Lower Saxony basins). The Neuquen and NW European basins lay at similar palaeolatitudes south and north of the equator, and there are striking similarities between some of the immigrants to the two areas. Links between the NW European and other South American faunas suggest a possible direct marine connection between the two areas. Copyright © 2007 John Wiley & Sons, Ltd.

Two tuffs in the Lower Cretaceous Agrio Formation, Neuquén Basin, provided U–Pb zircon radioisotopic ages of 129.09±0.16 Ma and 127.42±0.15 Ma. Both horizons are well constrained biostratigraphically by ammonites and nannofossils and can be correlated with the ‘standard’ sequence of the Mediterranean Province. The lower horizon is very close to the base of the Upper Hauterivian and the upper horizon to the Hauterivian/Barremian boundary, indicating that the former lies at c. 129.5 Ma and the latter at c. 127 Ma. These new radioisotopic ages fill a gap of over 8 million years in the numerical calibration of the current global Early Cretaceous geological time scale. Fil: Aguirre-Urreta, Maria Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos ; Argentina Fil: Lescano, Marina Aurora. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos ; Argentina Fil: Schmitz, Mark. Boise State University; Estados Unidos Fil: Tunik, Maisa Andrea. Universidad Nacional de Rio Negro. Sede Alto Valle; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Concheyro, Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos ; Argentina Fil: Rawson, Peter F.. University Of Hull; Reino Unido. University College London; Estados Unidos Fil: Ramos, Victor Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos ; Argentina

The status of the Quaternary, long regarded as a geological period effectively coincident with the main climatic deterioration of the current Ice Age, has recently been questioned as a formal stratigraphic unit. We argue here that it should be retained as a formal period of geological time. Furthermore, we consider that its beginning should be placed at the Gauss-Matuyama magnetic chron boundary at about 2.6 Ma, rather than at its current position at about 1.8 Ma. The Quaternary would be formally subdivided into the Pleistocene and Holocene epochs. The global chronostratigraphical correlation table proposed is enclosed at the back of this issue.

We present new data on 87Sr/86Sr, δ13C and δ18O, and elemental compositions of belemnites from 85 m of Valanginian, Hauterivian and Barremian strata at Speeton, Yorkshire, eastern England. The 87Sr/86Sr data provide a global standard for 87Sr/86Sr isotopic dating, and correlation to the biostratigraphic schemes of NW Europe. Values of 87Sr/86Sr increase from 0.707380±0.000003, at the base of the Hauterivian, to 0.707493±0.000004 in the earliest Late Barremian Paracrioceras elegans ammonite Zone before decreasing thereafter towards an Aptian minimum. The downturn in the elegans Zone coincided with the onset of volcanism on the present Ontong Java Plateau. A linear interpretation of the 87Sr/86Sr profile shows that the relative durations of ammonite zones differ by a factor ≤18. The basal Hauterivian unconformably overlies Valanginian strata; the discontinuity in 87Sr/86Sr across this surface represents a gap in sedimentation of 2.0 myr. In our belemnites (mostly of the genera Hibolites, Acroteuthis, and Aulacoteuthis) the absence of a correlation between δ18O and δ13C suggests that strong non-equilibrium fractionation has not affected the isotopic composition of the calcite. Our δ18O values therefore approximate to a valid record of marine palaeo-temperatures. Specimens of the genus Hibolites have δ18O values that are 0.4‰ more positive than those of co-occurring specimens of the genus Acroteuthis. This offset may be explained as resulting from small (0.4‰) departures from equilibrium during precipitation of calcite, different depth habitats, or changing temperature in the Speeton sea in the time that elapsed between deposition of our individual belemnites. The averaged belemnite record of δ18O through the section shows that seawater warmed from around 11°C at the base of the Hauterivian to a maximum around 15°C in the middle of the Hauterivian regale Zone, and returned to a cooler temperature of around 11°C by the middle of the overlying inversum Zone, a temperature that persisted to the basal Barremian. Through the Barremian, temperature increased to a peak of 20°C in the early Late Barremian elegans Zone then, in the same zone, precipitately and temporarily decreased to around 14°C at about the time of onset of volcanism on the Ontong Java Plateau, before they returned to around 16°C in the uppermost part of the section. In specimens of Aulacoteuthis and Acroteuthis, a good correlation between δ18O and the content of Na, Sr, and Mg suggests that incorporation of these trace elements in these genera is largely controlled by temperature. The dependency of concentration on temperature ranges from 7 to 20% per degree Celsius, if equilibrium fractionation of oxygen isotopic composition is assumed, so the Mg, Na and Sr content of these genera may be used as palaeo-temperature proxies. The trace element content of Hibolites shows no relation to stable oxygen isotopic composition and so does not record palaeo-temperature.

Holcoptychites is known only from the Neuquén Basin, Argentina, but appears close to the more widespread genera Jeanthieuloyites and Spitidiscus. Thus it is placed in the subfamily Spitidiscinae (Family Holcodiscidae). Previously described Holcoptychites species are revised and their taxonomy clarified, while one new species is left under open nomenclature. The sequence of forms allows two subzones to be recognized. These are correlated provisionally with the lowest Hauterivian Acanthodiscus radiatus Zone of the Mediterranean region. Fil: Aguirre-Urreta, Maria Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Rawson, Peter F.. Colegio Universitario de Londres; Reino Unido

The Lower Cretaceous Ammonite Working Group forms part of the IUGS Subcommission on Cretaceous Stratigraphy (Peter Rawson, chair) and is the successor of the Lower Cretaceous Cephalopod Team that formed part of IGCP Projects 262 and 362 respectively. The latter team had organized five Workshops (Klein & Hoedemaeker, 1999;Hoedemaeker & Rawson, 2000) and this is the first workshop under the new IUGS umbrella, which was organized by Stéphane Reboulet (Université de Lyon 1) directly after the 3rd French Symposium on Stratigraphy (Lyon, 8–10 July 2002). The workshop was attended by 18 members from 13 countries. The attendants agreed to call the group the ‘Kilian Group' after the famous French palaeontologist W. Kilian. Fil: Hoedemaeker, Philip J.. National Museum of Natural History; Países Bajos Fil: Reboulet, Stéphane. Universite´ Claude Bernard Lyon 1; Francia Fil: Aguirre-Urreta, Maria Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Alsen, Peter. Universidad de Copenhagen; Dinamarca Fil: Aoutem, Mohamed. Université d’Agadir Faculté des Sciences; Marruecos Fil: Atrops, François. Universite´ Claude Bernard Lyon 1; Francia Fil: Barragan, Ricardo. Universidad Nacional Autónoma de México; México Fil: González Arreola, Celestina. Universidad Nacional Autónoma de México; México Fil: Klein, Jaap. No especifica; Fil: Lukeneder, Alexander. Universidad de Viena; Austria Fil: Ploch, Isabela. Polish Geological Institute; Polonia Fil: Raisossadat, Seyed Naser. Colegio Universitario de Londres; Reino Unido Fil: Rawson, Peter F.. University Of Birjand; Irán Fil: Ropolo, Pierre. No especifica; Fil: Vasícek, Zdenek. VSB Inst. Geological Engineering; República Checa Fil: Vermeulen, Jean. No especifica; Fil: Wippich, Max G.E.. Ruhr Universität Bochum; Alemania

Hoplitocrioceras is a poorly-known ammonite genus of late Early Hauterivian age that may be endemic to the Neuquén Basin Argentina where it occurs at a clearly defined horizon in the Agrio Formation. It is an unusual genus with uncoiling (crioceratitid) whorls that remain linked by a thick dorsal shell that drapes over the tips of sharp upwardly-pointing ventro-lateral spines. It has been interpreted as either a necomitis or a crioceratitid but is here regarded as one of the last members of the Family Neocomitidae. One new species is proposed: H. giovinei. Fil: Aguirre-Urreta, Maria Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Rawson, Peter F.. Colegio Universitario de Londres; Reino Unido

A single Duvalia sp. is recorded from Shell well 22/26a-2 in the Central North Sea. Both the belemnite and some of the associated nannofossils indicate a Tethyan immigration horizon dated as early Late Barremian. The immigration route may have been via a North Atlantic seaway lying to the west of Britain.

Detailed stratigraphic logging and systematic studies on late Valanginian–early Barremian ammonites from the Agrio Formation of the Neuquen Basin of west-central Argentina, have provided a detailed local ammonite zonation. Here we combine the ammonite data with an initial study of calcareous nannofossils and palynomorphs from two sections to produce a provisional integrated biostratigraphy for the Agrio Formation. While the palynomorphs are essentially of local value only, especially the continental forms, the nannofossils and the ammonites allow some correlations to be made with the European Mediterranean `standard' sequences.

Viluceras is proposed as a new subgenus of Olcostephanus to accommodate a distinctive Argentinian Lower Cretaceous (Upper Valanginian) ammonite fauna originally assigned to the boreal genus Simbirskites and subsequently placed in Lemurostephanus . Based on extensive new collections from eight localities in the Neuquen Basin, three Viluceras species are described, including O. (Viluceras) duraznoensis sp. nov. With them occur rare O. (Olcostephanus) mingrammi (Leanza). The fauna characterises the Olcostephanus (Viluceras) permolestus Subzone, which may correlate approximately with the Himantoceras trinodosum Zone of the West Mediterranean Province.

A multidisciplinary colligation including new data and analysis of the evidence for the climates of southern Britain during c. 140 Ma. to c. 120 Ma BP (Berriasian-Barremian — ? earliest Aptian). The climate was at first hot, semi-arid and ‘Mediterranean’ (rather than ‘monsoonal’) in type, probably with seasonally opposed winds (E/W). An irregular long-term trend of increasing rainfall in the moister seasons is evident. This was probably associated with establishment of predominant westerlies during the Jurassic-Cretaceous transition and slightly lower average annual temperatures thereafter until Barremian times. Causes proposed are frequent changes in the regional climatic system due to technically induced adjustments of relief under the special conditions of the semi-enclosed Purbeck–Wealden archipelago and increasing proximity of the widening Protoatlantic sea.

The Agrio Formation of the Neuquén Basin, Argentina, contains an extensive sequence of ammonite faunas, most of which are monogeneric. Detailed collecting through 15 sections across the basin has facilitated a major revision of the ammonite zonation. Formerly embracing four broad zones, the Agrio Formation is now divided into nine zones, the lowest four of which are divided into a total of 11 subzones. The new zonation provides a standard against which other South American faunas can be compared. The degree of subdivision now achieved is comparable to that for the ‘standard’ sequences of the West Mediterranean region. Although it is not possible to correlate the two regions in detail, the occurrence of some widely distributed genera (Olcostephanus, Karakaschiceras, Oosterella, Spitidiscus and Crioceratites) at well-defined levels in the Neuquén Basin provides some crucial links. Thus the approximate positions of the Lower/Upper Valanginian, Valanginian/Hauterivian and Lower/Upper Hauterivian boundaries can be determined.

Mass extinctions are recognized through the study of fossil groups across event horizons, and from analyses of long-term trends in taxonomic richness and diversity. Both approaches have inherent flaws, and data that once seemed reliable can be readily superseded by the discovery of new fossils and/or the application of new analytical techniques. Herein the current state of the Cretaceous-Tertiary (K-T) biostratigraphical record is reviewed for most major fossil clades, including: calcareous nannoplankton, dinoflagellates, diatoms, radiolaria, foraminifera, ostracodes, scleractinian corals, bryozoans, brachio-pods, molluscs, echinoderms, fish, amphibians, reptiles and terrestrial plants (macrofossils and palynomorphs). These reviews take account of possible biasing factors in the fossil record in order to extract the most comprehensive picture of the K-T biotic crisis available. Results suggest that many faunal and floral groups (ostracodes, bryozoa, ammonite cephalopods, bivalves, archosaurs) were in decline throughout the latest Maastrichtian while others (diatoms, radiolaria, benthic foraminifera, brachiopods, gastropods, fish, amphibians, lepidosaurs, terrestrial plants) passed through the K-T event horizon with only minor taxonomic richness and/or diversity changes. A few microfossil groups (calcareous nannoplankton, dinoflagellates, planktonic foraminifera) did experience a turnover of varying magnitudes in the latest Maastrichtian-earliest Danian. However, many of these turnovers, along with changes in ecological dominance patterns among benthic foraminifera, began in the latest Maastrichtian. Improved taxonomic estimates of the overall pattern and magnitude of the K-T extinction event must await the development of more reliable systematic and phylogenetic data for all Upper Cretaceous clades.

Spitidiscus is a widely-distributed Hauterivian genus that briefly invaded the Neuquén Basin, Argentina, in mid Hauterivian times, well after it first evolved in the west Tethyan area. Its appearance in Argentina is linked with a globally-significant mid Hauterivian sea-level rise. This is marked in the basin by a sharp facies change in the Agrio Formation, from non-marine sandstones of the Avilé Member to marine sediments, often laminated black shales, with Spitidiscus at the base of the overlying Agua de la Mula Member. Our extensive field work has shown that Spitidiscus occurs across the whole basin, where it is represented by two species, Spitidiscus riccardii Leanza and Wiedmann and Spitidiscus kilapiae sp. nov. For most of its vertical range Spitidiscus occurs alone, characterising the S. riccardii Zone. But at the top of its range it is joined by the first crioceratitid ammonites, their appearance marking the base of the Crioceratites schlagintweiti Zone. Fil: Rawson, Peter F.. University of Hull; Reino Unido. University College London; Reino Unido Fil: Aguirre-Urreta, Maria Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina

Sediment supply is a fundamental control on the architecture of sedimentary sequences. In clastic depositional environments, the volume of sediment being transported into the basin of deposition is strongly dependent on both the nature of the weathering regime in the hinterlands, and on runoff. During arid, low sea-level phases in the late Jurassic and early-mid-Cretacwous, clastic supply was reduced and long hiatuses became common at sequence boundaries or during maximum flooding. These hiatuses amalgamated where sediment starvation produced strongly condensed (“super-condensed”) sections. In intervening humid, higher sea-level phases, clastic supply was more abundant: hence thick sediment packages separate sequence boundaries, downlnpping surfaces should be apparent on seismic sections, and condensed sections become rare. Where carbonate deposition dominates over clastic, sediment formation is largely intrabasinal and the effects of palaeoclimate on sequence stratigraphy are less obvious. Knowledge of palaeoclimates may lead us to search for certain sequence stratigraphic patterns connected to changes in sediment supply.

8 pages; International audience; The 4th Kilian Group meeting (Dijon, France, 30th August 2010) focused on the Aptian and Albian Stages. For the Aptian, a two-fold division of the stage was adopted for the Mediterranean area with a boundary between the Dufrenoyia furcata and Epicheloniceras martini Zones. The main changes to the zonal scheme concern the Lower Aptian with: the introduction of a Deshayesites luppovi Subzone in the upper part of the Deshayesites oglanlensis Zone; the replacement of Deshayesites weissi by Deshayesites forbesi as new indexspecies of the second interval zone; the introduction of a Roloboceras hambrovi Subzone in the upper part of the D. forbesi Zone; and the subdivision of the D. furcata Zone into the D. furcata and Dufrenoyia dufrenoyi Subzones. For the Albian, the upper part of the Douvilleiceras mammillatum Zone (Lower Albian) is now characterized by a Lyelliceras pseudolyelli Subzone. The main amendments concern the Upper Albian. The base of this substage is defined by the base of the Dipoloceras cristatum Zone. Above it, the Upper Albian zonal scheme comprises in stratigraphic order the Mortoniceras pricei, Mortoniceras inflatum, Mortoniceras fallax, Mortoniceras rostratum, Mortoniceras perinflatum and Arrhaphoceras briacensis Zones.

The Anthropocene, an informal term used to signal the impact of collective human activity on biological, physical and chemical processes on the Earth system, is assessed using stratigraphic criteria. It is complex in time, space and process, and may be considered in terms of the scale, relative timing, duration and novelty of its various phenomena. The lithostratigraphic signal includes both direct components, such as urban constructions and man-made deposits, and indirect ones, such as sediment flux changes. Already widespread, these are producing a significant ‘event layer’, locally with considerable long-term preservation potential. Chemostratigraphic signals include new organic compounds, but are likely to be dominated by the effects of CO 2 release, particularly via acidification in the marine realm, and man-made radionuclides. The sequence stratigraphic signal is negligible to date, but may become geologically significant over centennial/millennial time scales. The rapidly growing biostratigraphic signal includes geologically novel aspects (the scale of globally transferred species) and geologically will have permanent effects.

The Neuquén Basin is a stratigraphically- and economically-important Early Cretaceous depocentre located in west-central Argentina. The Early Valanginian to Early Barremian succession (upper Vaca Muerta, Mulichinco and Agrio Formations) contains a rich fossil record, with abundant bivalves and ammonoids. Palaeosalinities are determined systematically throughout the succession, based on an oxygen isotope analysis of unaltered oyster shells from two localities in Neuquén province. A total of 188 oyster samples from 52 stratigraphic levels were processed. A total of 52 mean values of δ18O isotope are used to calculate palaeosalinities, assuming an estimated water temperature of 25 °C. The observed range of palaeosalinities, between the maximum and the minimum, is 19, which is in conflict with published accounts of this being a fully marine succession. The isotopic data are combined with independent faunal evidence to evaluate palaeosalinity variation both laterally and temporally. Significant fluctuations in water salinity are indicated, with a clear tendency to increase from brachyhaline to euhaline and near hyperhaline conditions through time. The fluctuations were probably due to dilution from normal marine water, caused primarily by variations in rainfall and continental runoff. In addition, the presence of a volcanic island arc along the western margin of the basin may have at least partially isolated the basin from the marine waters of the Pacific Ocean. Also, a gulf-shaped basin may have inhibited hydrodynamic exchange with the ocean while enhancing retention of continental waters. Fil: Lazo, Dario Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Aguirre-Urreta, Maria Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Price, Gregory D.. University of Plymouth; Reino Unido Fil: Rawson, Peter F.. Colegio Universitario de Londres; Reino Unido Fil: Ruffell, Alastair H.. The Queens University of Belfast; Irlanda Fil: Ogle, N.. The Queens University of Belfast; Irlanda

The Chañarcillo and Neuquén basins of the Central Andes shared a common geological history in the earlier part of the Early Cretaceous but from Barremian times onward their evolution began to diverge, probably due to an increasing activity of an intervening volcanic arc. The Berriasian to Lower Barremian sequences were mainly marine and include rich ammonoid faunas, with many taxa in common to both the basins. They include both Andean and near-pandemic forms, the latter providing some good correlation levels with the 'standard' Mediterranean sequence. Marine conditions persisted in the Chañarcillo Basin till Early Albian times; the associated ammonoid faunas include pandemic, Pacific and Antarctic genera. In contrast, in the Neuquén Basin evaporites and continental clastics of the Huitrín Formation mark the beginning of a long disconnection with the Pacific Ocean, though a short-lived marine incursion is represented by the carbonates of La Tosca Member of the Huitrín Formation. The ammonoid faunas of the two basins are compared here, and a detailed biostratigraphic division of the sequences is discussed and compared with the Mediterranean succession. Fil: Aguirre-Urreta, Maria Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Mourgues, Amaro F.. Servicio Nacional de Geología y Minería; Chile Fil: Rawson, Peter F.. University College London; Reino Unido Fil: Bulot, Luc G.. Universite de Provence; Francia Fil: Jaillard, Etienne. IRD–LGCA, Maison des Géosciences; Francia

The Berriasian-Aptian succession in the Neuquén Basin is mainly marine in the lower part and non-marine in the upper portion. A detailed ammonite zonation is presented for the Berriasian-?Early Barremian interval. While some ammonite taxa are endemic, others are widely distributed and there are several levels where correlation can be suggested with the 'standard' stages and zones of the Tethyan Mediterranean area. Several nannofossil bioevents are recognized, and these provide evidence for correlation with Tethyan areas. Correlations suggested by both groups are reasonably consistent. Berriasian-Aptian palynomorphs include both terrestrial and marine forms. Several terrestrial assemblages can be recognized, but the marine forms are mainly long-ranging taxa, especially in the Agrio Formation. Fil: Aguirre-Urreta, Maria Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Rawson, Peter F.. Colegio Universitario de Londres; Reino Unido Fil: Concheyro, G. Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Bown, Paul R.. Colegio Universitario de Londres; Reino Unido Fil: Ottone, Eduardo Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina

We propose ending the distinction between the dual stratigraphic terminology of time-rock units (of chronostratigraphy) and geologic time units (of geochronology). The long-held, but widely misunderstood, distinction between these two essentially parallel time scales in stratigraphy has been rendered unnecessary by the widespread adoption of the global stratotype sections and points (GSSP-golden spike) principle in defining intervals of geologic time within rock strata. We consider that the most appropriate name for this stratigraphic discipline is "chronostratigraphy," which would allow "geochronology" to revert to its mainstream and original meaning of numerical age dating. This in turn makes the little-used formal term "geochronometry" redundant. The terms "eonothem," "erathem," "system," "series," and "stage" would become redundant, in favor of "eon," "era," "period," "epoch" and (disputably) "age." Our favored geologic time units may be qualified by "early" and "late," but not by "lower" and "upper." These suggested changes should simplify stratigraphic practice, encompass both stratified and nonstratified rocks, and help geologic understanding, while retaining precision of meaning.

The olcostephanid fauna of the Olcostephanus (O.) laticosta [formerly O. (O.) leanzai] Subzone (Agrio Formation) represents the last of four discrete invasions of olcostephanid ammonites into the Neuquén Basin of west-central Argentina. Olcostephanus (O.) laticosta (Gerth) dominates the fauna and is known only from the Neuquén Basin. But the co-occurrence of the distinctive subgenus Feannoticeras, newly recorded from Argentina, provides a link with the 'standard' West Mediterranean sequence and indicates that the O. (O.) laticosta Subzone is probably of mid Early Hauterivian age. This is supported by the discovery of two specimens of the widely distributed late Early Hauterivian species O. (O.) variegatus (Paquier) in the overlying Hoplitocrioceras giovinei Subzone. O. (Jeannoticeras) agrioensis sp. nov. is described. Fil: Aguirre-Urreta, Maria Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Rawson, Peter F.. Colegio Universitario de Londres; Reino Unido

List of contributors Preface 1. Introduction Stephen J. Culver and Peter F. Rawson 2. The Cretaceous world Andrew S. Gale 3. The Cenozoic world Kevin T. Pickering 4. Calcareous nannoplankton and global climate change Jackie A. Burnett, Jeremy R. Young and Paul R. Bown 5. Phenotypic response of foraminifera to episodes of global environmental change Norman Macleod, Nievez Ortiz, Nina Fefferman, William Clyde, Christine Schulter and Jena Maclean 6. The response of planktonic formanifera to the Late Pliocene intensification of Northern Hemisphere glaciation Mark R. Chapman 7. The response of Cretaceous cephalopods to global change Peter F. Rawson 8. Global change and the fossil fish record: the relevance of systematics Peter Forey 9. Response of shallow water foraminiferal paleocommunities to global and regional environmental change Stephen J. Culver and Martin A. Buzas 10. Intrinsic and extrinsic controls on the diversification of the Bivalvia J. Alistair Crame 11. Global events and biotic interaction as controls on the evolution of gastropods Noel Morris and John Taylor 12. Algal symbiosis, and the collapse and recovery of reef communities: Lazarus corals across the K-T boundary Brian R. Rosen 13. Changes in the diversity, taxic composition and life-history patterns of echinoids over the past 145 million years Andrew B. Smith and Charlotte H. Jeffery 14. Origin of the modern bryozoan fauna Paul D. Taylor 15. Angiosperm diversification and Cretaceous environmental change Richard Lupia, Peter R. Crane and Scott Lidgard 16. Cenozoic evolution of modern plant communities and vegetation Margaret E. Collinson 17. Leaf physiognomy and climate change Robert A. Spicer 18. Biotic response to Late Quaternary global change - the pollen record: a case study from the Upper Thames Valley, England Adrian G. Parker 19. The Cretaceous and Cenozoic record of insects (Hexapoda) with regard to global change Andrew J. Ross, Ed A. Jarzembowski and Stephen J. Brooks 20. The palaeoclimatological significance of Late Cenozoic Coleoptera: familiar species in very unfamiliar circumstances G. Russell Coope 21. Amphibians, reptiles and birds: a biogeographical review Angela C. Milner, Andrew R. Milner and Susan E. Evans 22. Paleogene mammals: crises and ecological change Jeremy J. Hooker 23. Response of Old World terrestrial vertebrate biotas to Neogene climate change Peter J. Whybrow and Peter Andrews 24. Mammalian response to global change in the later Quaternary of the British Isles Andrew Currant 25. Human evolution: how an African primate became global Chris Stringer 26. The biotic response to global change: a summary Stephen J. Culver and Peter F. Rawson References Index.

INTRODUCTION What comes over so clearly in the contributions to this volume is that the nature and rates of biotic response to global change have been very variable. While many biotic groups show a marked response to the physical variables of global change considered in Chapters 2 and 3, in others the main changes over the last 145 Ma have been driven primarily by intrinsic or extrinsic biological factors. Furthermore, any organisms that contributed substantially to carbon burial (e.g. trees, corals, nannofossils) helped to drive global change. In this chapter we bring together some of the common strands that have emerged from the preceding chapters. ENVIRONMENTAL CONSIDERATIONS AND BIOTIC RESPONSE Climate change, itself a product of other components of global change, is a key forcing mechanism for global biotic change. The time interval embraced by this volume witnessed a major change in Earth's climatic history, from a very warm ‘greenhouse’ state in the Cretaceous through a long, but far from monotonic, decline through much of the Cenozoic to the present-day icehouse world. During the ‘green-house’ phase, climate varied but apparently changed only slowly over many thousand to several million years. But as global climate cooled a clearly marked cyclicity developed, driven by Milankovitch and sub-Milankovitch scale cycles.

Valanginites, previously known from Argentina by a single specimen (holotype of V. argentinicus Leanza & Wiedmann), is recorded from two localities in the Neuquen Basin, each of which has yielded six specimens. It occurs just beneath a widely distributed Lissonia/Acantholissonia fauna that forms a distinctive level, here separated as the Lissonia riveroi Zone, in the top part of the Vaca Muerta Formation and its equivalents. Both these faunas occur well below a basal Upper Valanginian Karakaschiceras fauna. Hence Valanginites appears considerably earlier in Argentina than in Europe.

We thank Gong et al., Heckert et al., and Bassett et al. for their comments on our discussion paper. Their varied responses are typical of the range of responses we have received informally and that have been published elsewhere (e.g., Ogg, cf. Edwards in [Pratt, 2004][1]), from enthusiastic support