THE EVOLUTIONARY LINEAGES OF THE MAASTRICHTIAN PLANKTIC FORAMINIFERA GENUS Plummerita IN THE TETHYS

Minor differences in the morphology of the test, wall structure, arrangement of chambers and apertures, size are recognized as being of decisive specific or subspecific value. Twenty four phylogenetic lineages were produced by puncuated equilibrium and gradualistic evolutionary trends which observed within 50 benthic foraminiferal species and subspecies belonging to 18 genera throughout the Maastrichtian to Priabonian forms in Tethys as well as one recent species by the present authors and others. In this study, new eight lineages are presented: Clavulina parisiensis d'Orbigny ˃ C. pseudoparisensis Anan, Laevidentalina granti (Plummer) ˃ L. salimi Anan, Lenticulina carinata (Plummer) ˃ L. turbinata (Plummer) ˃ L. chitanii (Yabe and Asano), Percultazonaria ameeri Anan ˃ P. allami Anan, Percultazonaria alii Anan ˃ P. longiscata (Nakkady), Percultazonaria wadiarabensis (Futyan) ˃ P. tuberculata (Plummer), Palmula woodi undulata Nakkady ˃ P. w. woodi Nakkady, Gavelinella b. brotzeni Said and Kenawy ˃ G. brotzeni paleocenica Said and Kenawy. These lineages help, not only to define the major faunal changes at the Cretaceous/Tertiary (K/T) and the Paleocene/Eocene (P/E) boundaries, but also to emphasis the stratigraphic importance of them in different localities in the Tethys.

Abstract. In this study, published Holocene ostracod data for Osaka, Hiroshima, and Iyo-nada Bays within the Seto Inland Sea (SIS), Japan, are re-examined. Five major faunal changes are recognized at different stratigraphic horizons (Horizons 1–5) in the Holocene sedimentary record. Horizons 1 and 5 (faunal changes) were most likely triggered by the respective openings of the Bisan-seto (and resulting formation of the SIS) and Akashi Straits. Three other major faunal changes, at Horizons 2–4, may also be linked to the opening of straits and resulting formation of bays, although the exact nature of these events is less certain. This re-examination indicates that the opening of straits extensively affected the benthic inner-bay community during the Holocene transgression in the SIS. Further high-resolution studies are needed for confirmation of faunal changes triggered by opening of straits.

During the last four decades ago, fifty-seven (54 agglutinated and 3 porcelaneous) benthic foraminiferal species and related to 23 genera have been erected by the present author, which start at 1984, which are recoded from many countries around the Arabia (Egypt, Palestine, Jordan, Iraq, UAE, Iran and Pakistan), and also Saudi Arabia, Yemen, UAE and Qatar. Some of these species were also recorded from many countries in the Northern Tethys (Atlantic Ocean, USA, Spain, France and Poland), and western Pacific Ocean. These species help, not only to define the major faunal changes throughout the Campanian-Neogene time, but also to emphasis the stratigraphic importance of them in different localities in the Tethys. Most of the identified species were erected: 12 species (from Egypt), 11 (UAE), 8 (Iraq), 4 (Iran), 3 (Pakistan and France), 2 (Palestine, Pakistan, Spain and Poland), while one species only from the other countries. The Tethys assemblage indicates an open marine environment, which represents middle-outer neritic environment and shows an affinity with Midway-Type Fauna (MTF).

The mid-to late Miocene Lake was a primarily closed, saline lake which during its lifetime underwent a series of rapid salinity changes associated with faunal extinctions/radiations. The first two of these, at the Badenian/Sarmatian and Sarmatian/Pannonian boundaries signify the transition from a marine basin to a brackish lake and are marked by major faunal changes. The isotopic composition of molluscs from the lake, however, does not undergo major changes. The third transition, at the end of the Pannonian and into the Pontian, is also marked by major faunal changes, thought initially to reflect further freshening of the lake. Both carbon and oxygen isotope ratios of lake molluscs decrease by 4 to 6%oo at this transition. A consideration of salinity and oxygen isotope mass balances for a closed or nearly-closed lake shows that major changes in salinity accompany relatively minor changes in water balance and isotopic composition. This result explains why the oxygen isotope ratio of lake waters did not change during the initial freshening of the lake and suggests that the major isotopic changes observed later are not directly related to changes in the lake water balance which caused the salinity changes. The isotopic variations were driven mainly by other climatic factors, most likely changes in humidity and isotopic composition of inflow.

Faunal lists are presented of the successive beds, either excavated or sampled, in four different sections of the localities at Atapuerca and lbeas de Juarros, Burgos. Considerations follow on the climate and other ecological conditions which may have influenced fossil preservation and the paleofaunal composition of each bed. Correlations are considered between the different sections of Atapuerca and European local fauna. Lower beds of Gran Dolina (TD.3-6) and Penal (TP.3-7) yield abundant remains of a known faunal association lasting with little change from late Early Pleistocene (after Jaramillo) to the West-Runton Freshwater Beds (Cromer Forest Beds). The upper beds of Atapuerca in Gran Dolina (TD.10-11) and the 'Tres Simas' complex (CTS3) are correlated on the ground of their faunal assemblages with those of the mid-upper Middle Pleistocene of Europe, La Fage, Bilzingsleben, Swanscombe, Steinheim 2, Castel di Guido, Malagrotta, Ehringsdorf, which may be correlated to OIS episode 9, or 7. The intermediate beds of Gran Dolina (TD.7-8) have not yet been excavated; the excavation of the intermediate unit of the Tres Simas Complex (CTS.2) was started on/y recently, so that the present author only knows its faunal content from early sampling.It can be predicted that these assemblages, when recovered, will resemble those known from Mauer, L'Escale, Belle-Roche, Cava Pompi, Arago, Lunel-Viel, Westbury 2, which represent major faunal changes in Europe over 500 kaBP and about 400 kaBP. The fossil humans and associated remains in «Sima de los Huesos» probably correspond to that median part of the Middle Pleistocene. Additional considerations deal with ecological factors that may have influenced the European faunal associations over that time span, with archaeological remains related lo them. Changes are shown, and questions posed for future research.

Deep-sea benthonic foraminiferal faunal turnover near the Eocene/Oligocene boundary

The Eocene-Oligocene is a time of transition from a warm early Tertiary world with low vertical and latitudinal thermal gradients to the Neogene world with steep vertical oceanic gradients and high latitudinal gradients between equator and poles. The transition between these two regimes occurred primarily between the middle Eocene and middle Oligocene and can be observed in faunal and floral assemblage changes, associated paleotemperature changes, periodic current intensification as implied by increased carbonate dissolution and hiatuses, eustatic sea level changes, and the curious association of microtektites and iridium anomalies with several of these intervals. Population studies of planktonic foraminifers in 14 DSDP sites in the Atlantic, Pacific, and Indian Oceans indicate a general cooling trend between the middle Eocene and Oligocene. Major faunal changes indicating cooling episodes occur, however, at discrete intervals: middle Eocene 44 to 43 Ma (P13); middle/late Eocene boundary 41 to 40 Ma (P14/P15); late Eocene 39 to 38 Ma (P15/P16); Eocene/Oligocene boundary 37 to 36 Ma (P18); and late Oligocene 31 to 29 Ma (P20/P21). Each cooling episode resulted in the extinction of warmer water species and evolution and dominance of cooler water species. This trend is associated with the development of a steep vertical thermal gradient and resulting stratification in the upper water masses (0 to 300 m, 1,000 ft) in the latest Eocene. 18The presence of microtektites and iridium anomaly in latest Eocene sediments has resulted in the scenario of catastrophic extinctions due to a bolide impact. The present study reveals multiple microtektite occurrences at 43 Ma, 40 Ma, 38 Ma, 34 Ma, and 30 Ma. Moreover, these microtektite occurrences coincide with intervals of increased carbonate dissolution and/or hiatuses. This suggests that microtektites are concentrated as a result of carbonate dissolution and selective winnowing of sediments at these intervals. Consequently, a concentration of microtektites in deep-sea sediments may not always imply a bolide impact, nor is there any evidence of catastrophic extinctions during Eocene-Oligocene time. End_of_Article - Last_Page 494------------

An integrated approach to taphonomy and faunal change in the Shungura formation (Ethiopia) and its implication for hominid evolution.

Like most sill fjords, Gullmar Fjord on the Swedish west coast, is subject to periods of stagnation. Deep water is usually renewed annually, but since the late 1970s several low-oxygen events have been documented in the deepest part of the fjord. These events occurred during a time when the North Atlantic Oscillation (NAO) was in a highly positive phase. We investigated how the benthic environment, in the deepest part of the fjord, has varied during the 20th century, using benthic foraminifera and an extensive history of instrumental hydrographic data. The foraminifera have undergone one major faunal change and two minor modifications during this time. The major faunal change occurred in the late 1970s to early 1980s, when the common Skagerrak-Kattegat fauna was replaced by one dominated by the opportunistic, low-oxygen-tolerant species,Stainforthia fusiformis. This major faunal change appears to be related to the severe low-oxygen event in 1979–1980. In the latter part of the 1990s the fauna changed again; the concentration ofS. fusiformis was still high, but other low-oxygen-tolerant species also became important. This minor faunal modification occurred in connection with the 2-yr stagnation period between 1996 and 1998 when a low-oxygenevent evolved, the most severe recorded in Gullmar Fjord. Between 1930 and 1980, there was little faunal variation, and a stable fjord environment is indicated. During this time, negative NAO indexes dominated and climate was more continental, with an increase in winds from the northeast and east. In connection with a climate transition indicated by the NAO index switching from positive to negative, a minor faunal change occurred in the late 1920s to early 1930s: the concentration of the Skagerrak-Kattegat fauna increased markedly in the fjord. The fauna characterizing the positive NAO phase between 1900 and the late 1920s is very different from the present positive NAO fauna. The foraminiferal record laid down between approximately 1914 and 2001 indicates that between 1930 and 1980 Gullmar Fjord was a stable fjord environment. During the last 20 yr, it experienced conditions that were more fluctuating and changing. For the most part, changes in the foraminiferal fauna are caused by changes in the deep-water renewal, their extent and frequency, which in turn are caused by climatic oscillations.

The Cretaceous/Tertiary boundary in the Gamba and Tingri regions of Tibet occurs between the Zongshan and Jidula Formations. Arenaceous facies similar to those of the Jidula Formation are widespread in Tibet and Pakistan; collectively, these represent the diachronous deposits of the Latest Cretaceous-Early Tertiary regression. Major faunal changes took place in Tibet during the Late Cretaceous. Ali of the Cretaceous ammonoids, planktonic and benthonic foraminifera, rudistid and inoceramid bivalves became extinct over the Campanian Maastrichtian interval in a stepwise pattern, with abrupt Late Campanian and Late Maastrichtian extinction events (Tabs. 3, 4). A large number of new taxa appeared during the Danian (Tabs. 3, 4). These faunal changes in the shallow-water marine facies of Tibet demonstrate that this region was not isolated from major global faunal changes taking place in the Cretaceous/Tertiary boundary mass extinction interval.

Benthic foraminifera and the late Quaternary (last 150 ka) paleoceanographic and sedimentary history of the Bounty Trough, east of New Zealand

We reconstructed late Quaternary deep (3000–4100 m) and intermediate depth (1000–2500 m) paleoceanographic history of the Eurasian Basin, Arctic Ocean from ostracode assemblages in cores from the Lomonosov Ridge, Gakkel Ridge, Yermak Plateau, Morris Jesup Rise, and Amundsen and Makarov Basins obtained during the 1991 Polarstern cruise. Modern assemblages on ridges and plateaus between 1000 and 1500 m are characterized by abundant, relatively species‐rich benthic ostracode assemblages, in part, reflecting the influence of high organic productivity and inflowing Atlantic water. In contrast, deep Arctic Eurasian basin assemblages have low abundance and low diversity and are dominated by Krithe and Cytheropteron reflecting faunal exchange with the Greenland Sea via the Fram Strait. Major faunal changes occurred in the Arctic during the last glacial/interglacial transition and the Holocene. Low‐abundance, low‐diversity assemblages from the Lomonosov and Gakkel Ridges in the Eurasian Basin from the last glacial period have modern analogs in cold, low‐salinity, low‐nutrient Greenland Sea deep water; glacial assemblages from the deep Nansen and Amundsen Basins have modern analogs in the deep Canada Basin. During Termination 1 at intermediate depths, diversity and abundance increased coincident with increased biogenic sediment, reflecting increased organic productivity, reduced sea‐ice, and enhanced inflowing North Atlantic water. During deglaciation deep Nansen Basin assemblages were similar to those living today in the deep Greenland Sea, perhaps reflecting deepwater exchange via the Fram Strait. In the central Arctic, early Holocene faunas indicate weaker North Atlantic water inflow at middepths immediately following Termination 1, about 8500–7000 year B.P., followed by a period of strong Canada Basin water overflow across the Lomonosov Ridge into the Morris Jesup Rise area and central Arctic Ocean. Modern perennial sea‐ice cover evolved over the last 4000–5000 years. Late Quaternary faunal changes reflect benthic habitat changes most likely caused by changes in the import of cold, deepwater of Greenland Sea origin and warmer and middepth Atlantic water to the Eurasian Basin through the Fram Strait, and export of Arctic Ocean deepwater.Appendix Tables Al‐A4 are available on microfiche. Orderfrom the American Geophysical Union, 2000 Florida Avenue,N.W., Washington, DC 20009. Document P94‐002; $2.50.Payment must accompany order.

Cenozoic strata of the Beaufort-Mackenzie Basin were deposited in a series of 9 sequences on the continental margin of Arctic Canada. Seismostratigraphic and biostratigraphic (foraminiferal) schemes for analyzing these strata have evolved concurrently. Integration of these two methods is illustrated from selected Eocene to Miocene sections referenced to a transgressive-regressive sequence model. Marginal marine foraminiferal assemblages from seismic topset facies are low in diversity, dominantly agglutinated (Portatrochammina, Jadammina, Labros pira, Textularia), and markedly different in successive sequences. Mid-shelf deltaic facies are also dominated by agglutinated genera (Bathysiphon, Haplophragmoides, Insculptarenulla, Recurvoides, Reticulophragmium). In contrast, foraminiferal assemblages from non-deltaic, outer shelf to upper slope facies (seismic topsets to foresets) are mostly calcareous benthic species. In continental-rise facies (seismic bottomset facies), agglutinated foraminifers are also abundant (Ammodiscus, Ammolagena, Bathysiphon, Cystammina, Glomospira, Haplophragmoides, Insculptarenulla, Reticulophragmium, Recurvoides, Reophax), but typically are long ranging. Lower slope to continental rise turbiditic deposits are mostly barren, except for reworked microfaunas. Faunal changes at sequence boundaries indicate the scope of tectono-oceanographic reorganization which generated each depositional episode. For example, major faunal changes encountered at sequence boundaries near the Eocene/Oligocene and Miocene/Pliocene boundaries reflect global-scale events.

Biochronology and paleoclimatic implications of Middle Eocene to Oligocene planktic foraminiferal faunas

Radiolarian faunal turnover and paleoceanographic change around Eocene/Oligocene boundary in the central equatorial Pacific, ODP Leg 199, Holes 1218A, 1219A, and 1220A