scholarly journals Fossil plant stomata indicate decreasing atmospheric CO<sub>2</sub> prior to the Eocene–Oligocene boundary

2016 ◽  
Vol 12 (2) ◽  
pp. 439-454 ◽  
Author(s):  
Margret Steinthorsdottir ◽  
Amanda S. Porter ◽  
Aidan Holohan ◽  
Lutz Kunzmann ◽  
Margaret Collinson ◽  
...  
Keyword(s):  
Late Eocene ◽  
Large Shift ◽  
Stratigraphic Sequence ◽  
Multiple Data ◽  
Fossil Leaves ◽  
Two Samples ◽  
Data Points ◽  
Rapid Temperature ◽  
Latest Eocene ◽  
Climate Mode

Abstract. A unique stratigraphic sequence of fossil leaves of Eotrigonobalanus furcinervis (extinct trees of the beech family, Fagaceae) from central Germany has been used to derive an atmospheric pCO2 record with multiple data points spanning the late middle to late Eocene, two sampling levels which may be earliest Oligocene, and two samples from later in the Oligocene. Using the inverse relationship between the density of stomata and pCO2, we show that pCO2 decreased continuously from the late middle to late Eocene, reaching a relatively stable low value before the end of the Eocene. Based on the subsequent records, pCO2 in parts of the Oligocene was similar to latest Eocene values. These results suggest that a decrease in pCO2 preceded the large shift in marine oxygen isotope records that characterizes the Eocene–Oligocene transition and that when a certain threshold of pCO2 change was crossed, the cumulative effects of this and other factors resulted in rapid temperature decline, ice build up on Antarctica and hence a change of climate mode.

scholarly journals Fossil plant stomata indicate decreasing atmospheric CO<sub>2</sub> prior to the Eocene–Oligocene boundary

2015 ◽  
Vol 11 (5) ◽  
pp. 4985-5019 ◽  
Author(s):  
M. Steinthorsdottir ◽  
A. S. Porter ◽  
A. Holohan ◽  
L. Kunzmann ◽  
M. Collinson ◽  
...  
Keyword(s):  
Late Eocene ◽  
Large Shift ◽  
Stratigraphic Sequence ◽  
Multiple Data ◽  
Fossil Leaves ◽  
Two Samples ◽  
Data Points ◽  
Rapid Temperature ◽  
Latest Eocene ◽  
Climate Mode

Abstract. A unique stratigraphic sequence of fossil leaves of Eotrigonobalanus furcinervis (extinct trees of the beech family, Fagaceae) from central Germany has been used to derive an atmospheric pCO2 record with multiple data points spanning the late middle to late Eocene, two sampling levels which may be earliest Oligocene, and two samples from later in the Oligocene. Using the inverse relationship between the density of stomata and pCO2, we show that pCO2 decreased continuously from the late middle to late Eocene, reaching a relatively stable low value before the end of the Eocene. Based on the subsequent records, pCO2 in parts of the Oligocene was similar to latest Eocene values. These results show that a decrease in pCO2 preceded the large shift in marine oxygen isotope records that characterizes the Eocene–Oliogocene transition. This may be related to the "hysteresis effect" previously proposed – where a certain threshold of pCO2 change was crossed before the cumulative effects of this and other factors resulted in rapid temperature decline, ice build up on Antarctica and hence a change of climate mode.

scholarly journals New phiocricetomyine rodents (Hystricognathi) from the Jebel Qatrani Formation, Fayum Depression, Egypt

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12074
Author(s):  
Shorouq F. Al-Ashqar ◽  
Erik R. Seiffert ◽  
Dorien de Vries ◽  
Sanaa El-Sayed ◽  
Mohamed S. Antar ◽  
...  
Keyword(s):  
New World ◽  
New Genus ◽  
Late Eocene ◽  
Type Locality ◽  
New Genus And Species ◽  
Additional Material ◽  
Early Oligocene ◽  
Species Type ◽  
The Rich ◽  
Latest Eocene

Background The rich rodent assemblages from the Eocene–Oligocene deposits of the Jebel Qatrani Formation (Fayum Depression, Egypt) have important implications for our understanding of the origin and paleobiogeography of Hystricognathi, a diverse clade that is now represented by the Afro-Asiatic Hystricidae, New World Caviomorpha, and African Phiomorpha. Methods Here we present previously undescribed material of the enigmatic hystricognath clade Phiocricetomyinae, from two stratigraphic levels in the lower sequence of the Jebel Qatrani Formation—a new genus and species (Qatranimys safroutus) from the latest Eocene Locality 41 (~34 Ma, the oldest and most productive quarry in the formation) and additional material of Talahphiomys lavocati from that species’ type locality, early Oligocene Quarry E (~31–33.2 Ma). Results The multiple specimens of Qatranimys safroutus from L-41 document almost the entire lower and upper dentition, as well as mandibular fragments and the first cranial remains known for a derived phiocricetomyine. Specimens from Quarry E allow us to expand comparisons with specimens from Libya (late Eocene of Dur at-Talah and early Oligocene of Zallah Oasis) that have been placed in T. lavocati, and we show that the Dur at-Talah and Zallah specimens do not pertain to this species. These observations leave the Fayum Quarry E as the only locality where T. lavocati occurs.

scholarly journals Reticulate Nummulites (N. fabianii Linage) and Age of the Pellatispira-Beds of the Drazinda Formation, Sulaiman Range, Pakistan

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Ozcan E
Keyword(s):  
Mediterranean Region ◽  
Late Eocene ◽  
Test Surface ◽  
Time Interval ◽  
Late Oligocene ◽  
Shallow Marine ◽  
Western Tethys ◽  
Two Samples ◽  
Evolutionary Scheme ◽  
Weak Surface

The Eocene shallow marine Pellatispira-beds in the upper part of the Drazinda Formation represent the latest phase of Cenozoic Tethyan marine deposition in the Sulaiman Range, West Pakistan. The unit consists of stratigraphically important taxa as Heterostegina,Silvestriella, Pellatispira, a new Baculogypsina (possibly ancestral to modern Baculogypsina) and reticulate Nummulites implying a latest middle to late Eocene (late Bartonian-Priabonian) age. A more precise age of the unit requires the biometric study of reticulate Nummulites, the evolutionary scheme of which is better known from the peri-Mediterranean region in the Tethys. This group, which was subdivided into a series of successive chrono-species based on the biometry of inner cross-diameter of proloculus and changes in the types of granulation/reticulation on the test surface in the late Eocene-late Oligocene interval, appears to have a significant biostratigraphic potential for a high-resolution biostratigraphy in the peri-Mediterranean region (Western Tethys). The reticulate Nummulites in two samples from Rakhi Nala and Zinda Pir, ZP22 and RNB10, were studied and compared with those from the peri-Mediterranean region. The isolated specimens have a weak surface granulation externally, a distinct small umbonal granule (pile) and typical reticulation. The samples ZP22 and RNB10 from Zinda Pir and and Rakhi Nala sections have an average inner cross diameter of proloculus of 152.0 and 153.0 μm respectively. The reticulate Nummulites in both samples are assigned to N. hormoensis, a chrono-species characteristic for the shallow benthic zone (SBZ 18), referable to latest Bartonian-early Priabonian time interval. Since Heterostegina in peri-Mediterranean region and in Pakistan belongs to different lineages, a correlation of N. hormoensis in the studied samples with the wellestablished evolutionary scheme of Heterostegina reticulata and H.armenica lineages from the Western Tethys was not possible.

Aphids, true hoppers, jumping plant-lice, scale insects, true bugs and whiteflies (Insecta: Hemiptera) from the Insect Limestone (latest Eocene) of the Isle of Wight, UK

2019 ◽  
Vol 110 (3-4) ◽  
pp. 331-396
Author(s):  
Jacek SZWEDO ◽  
Jowita DROHOJOWSKA ◽  
Yuri A. POPOV ◽  
Ewa SIMON ◽  
Piotr WEGIEREK
Keyword(s):  
New Taxa ◽  
Late Eocene ◽  
Scale Insects ◽  
Isle Of Wight ◽  
True Bugs ◽  
Latest Eocene

ABSTRACTRepresentatives of the Hemiptera: Sternorrhyncha, Fulgoromorpha, Cicadomorpha and Heteroptera from the Late Eocene of the Isle of Wight, UK, are analysed and discussed. Psylloidea were reviewed and a key to the described taxa is given. Aphidoidea were studied, previously described taxa revised and new taxa described. New taxa of Aphidoidea are Hormaphididae: Hormaphis? longistigma Wegierek sp. nov.; Eriosomatidae: Eriosoma gratshevi Wegierek sp. nov. and Colopha? incognita Wegierek sp. nov.; Drepanosiphidae: Panfossilis anglicus Wegierek gen. et sp. nov. and Betulaphis kozlovi Wegierek sp. nov. Previously described Fulgoromorpha were revised and new taxa are described. The homonym Hastites Cockerell, 1922 (Cixiidae) preoccupied by Hastites Mayer-Eymar, 1883 is replaced by Catulliastites Szwedo nom. nov. for Catulliastites muiri (Cockerell) comb. nov. New taxa described are Cixiidae: Klugga gnawa Szwedo gen. et sp. nov., Klugga regoa Szwedo sp. nov., Liwakka gelloa Szwedo gen et sp. nov., Delwa morikwa Szwedo gen. et sp. nov., Kommanosyne wrikkua Szwedo gen. et sp. nov., Kernastiridius nephlajeus Szwedo gen. et sp. nov., Margaxius angosus Szwedo gen. et sp. nov., Dweivera reikea Szwedo gen. et sp. nov., Samaliverus bikkanus Szwedo gen. et sp. nov., Komsitija tuberculata Szwedo gen. et sp. nov., Langsmaniko marous Szwedo gen. et sp. nov., Komnixta jarzembowskii Szwedo gen. et sp. nov. and Worodbera nimakka gen. et sp. nov.; Tropiduchidae: Reteotissus hooleyi Szwedo gen. et sp. nov., Phatanako gen. nov. for Phatanako wilmattae (Cockerell) comb. nov., Senogaetulia kwalea Szwedo gen. et sp. nov., Dakrutulia mikhailkozlovi Szwedo gen. et sp. nov., Keriophettus atibenus Szwedo gen. et sp. nov. and Sognotela emeljanovi Szwedo gen. et sp. nov.; Issidae: Krundia korba Szwedo gen. et sp. nov., Breukoscelis vadimgratshevi Szwedo gen. et sp. nov., Breukoscelis phrikkosus Szwedo sp. nov. and Uphodato garwoterus Szwedo gen. et sp. nov.; Nogodinidae: Ambitaktoinae Szwedo subfam. nov., Ambitaktoa stoumma Szwedo gen. et sp. nov., Phariberea gurdonika Szwedo gen. et sp. nov., Wixskimoa torxsea Szwedo gen. et sp. nov., and Nadrimini trib. nov. with Niadrima yulei Szwedo gen. et sp. nov.; Lophopidae: Ankomwarius brodiei Szwedo gen. et sp. nov.; Ricaniidae: Ankwlanno bluga Szwedo gen. et sp. nov. Previously described Cicadomorpha were revised and new taxa are described: Cicadidae: Kintusamo boulardi Szwedo gen. et sp. nov; Aphrophoridae: Blenniphora Szwedo gen. nov. for Blenniphora woodwardi (Cockerell) comb. nov., Blenniphora skaka Szwedo sp. nov. and Blenniphora bikkanoa Szwedo sp. nov.; Luisphantyelus briwus Szwedo gen. et sp. nov., Natajephora lijanka Szwedo gen. et sp. nov.; Cercopidae: Berro enissuextaensis Szwedo gen. et sp. nov.; Cicadellidae: Mileewinae: Teniwitta andrewrossi Szwedo gen. et sp. nov. Formerly described true bugs (Heteroptera) are revised and several new taxa are described – Nepomorpha: Corixidae: Diacorixites szwedoi Popov gen. et sp. nov.; Cimicomorpha: Tingidae: Parasinalda wappleri Popov sp. nov., Viktorgolubia Popov gen. nov. for Viktorgolubia seposita (Cockerell) comb. nov.; Miridae: Gurnardinia herczeki Popov gen. et sp. nov.; Pentatomomorpha: Lygaeidae: Gurnardobayini Popov trib. nov., Gurnardobaya rossi Popov gen. et sp. nov.; Cydnidae: Eocenocydnus lisi Popov gen. et sp. nov.; Pentatomidae: Podopinites coloratus Popov gen. et sp. nov. and Podopinites acourti (Cockerell) comb. nov. An overview of the Late Eocene fauna of the Hemiptera is presented. Ecological and biogeographical patterns of the Hemiptera from the Isle of Wight deposits are discussed.

The Relationship Between Affect and Performance in Competitive Intercollegiate Tennis: A Dynamic Conceptualization and Application

2007 ◽  
Vol 1 (2) ◽  
pp. 130-146 ◽  
Author(s):  
Michael B. Johnson ◽  
William A. Edmonds ◽  
Gershon Tenenbaum ◽  
Akihito Kamata
Keyword(s):  
Sport Psychology ◽  
Dynamic Nature ◽  
Performance Levels ◽  
Tennis Players ◽  
Multiple Data ◽  
Data Points ◽  
And Performance ◽  
Affective Intensity ◽  
The Relationship

A recently introduced probabilistic methodology (Kamata, Tenenbaum, & Hanin, 2002) was implemented in the current study to ascertain the idiosyncratic Individual Affect-related Performance Zones (IAPZs) of four intercollegiate tennis players. The current study advances upon previous empirical works by its use of multiple performance levels, use of athletes’ introspective affective intensity, and recording multiple data points duringcompetition. Results present within- and between-player comparisons, and highlight the dynamic nature of competitive athletic events. A brief discussion regarding the implications of this methodology and the pursuant results for sport psychology consultants is also proffered. Being idiosyncratic in nature, the observations from this study are not intended to generalize across samples, but rather to introduce how knowledge of the systematic and dynamic linkage between an individual’s affect and his or her performance can be uncovered and possibly used with individual athletes to facilitate more consistently optimal performances.

scholarly journals Perceived time slows during fleeting fun or fear

2018 ◽  
Vol 71 (2) ◽  
pp. 562-567 ◽  
Author(s):  
Mike Corke ◽  
Jason Bell ◽  
Stephanie C. Goodhew ◽  
Michael Smithson ◽  
Mark Edwards
Keyword(s):  
Temporal Processing ◽  
Weber’S Law ◽  
Emotional Stimuli ◽  
Weber's Law ◽  
Multiple Data ◽  
Data Points ◽  
Psychophysical Studies ◽  
Perceived Duration

Previous psychophysical studies at durations greater than 1000 ms have confirmed the anecdotal reports of an increase in the perceived duration of both positively and negatively valenced emotive stimuli; however, the results of studies at durations less than 1000 ms have been inconsistent. This study further investigated the effect of valence on the perception of durations less than 1000 ms. We used both positively and negatively valenced stimuli in order to compare their effects on the distortion of duration, and we tested multiple data points within the sub-one-second range. We found an increase in the perceived duration of both positively and negatively valenced emotional stimuli at all data points. This is consistent with studies at durations longer than 1000 ms and also with models of temporal processing. We also confirmed that Weber fractions, within the range tested, followed the generalized form of Weber’s law.

Eocene and Oligocene volcanism at Mount Petras, Marie Byrd Land: implications for middle Cenozoic ice sheet reconstructions in West Antarctica

2000 ◽  
Vol 12 (4) ◽  
pp. 477-491 ◽  
Author(s):  
T.I. Wilch ◽  
W.C. McIntosh
Keyword(s):  
Ice Sheet ◽  
Late Eocene ◽  
West Antarctica ◽  
Tuff Cone ◽  
Ice Cap ◽  
West Antarctic ◽  
Strombolian Eruptions ◽  
Intermittent Contact ◽  
External Water ◽  
Latest Eocene

Evidence for one late Eocene and four middle Oligocene eruptions of Mount Petras, Marie Byrd Land provides new insights into reconstructions of middle Tertiary ice sheet configurations, surface topography, and volcanism in West Antarctica. The interpretation presented here of the volcanic record at Mount Petras, based on detailed analyses of lithofacies, petrography, 40Ar/39Ar geochronology, and geochemistry, is significantly different from previous interpretations based on reconnaissance studies. A massive, 25 m thick, mugearite lava near the summit of Mount Petras is 40Ar/39Ar dated to 36.11 ± 0.22 Ma (2 σ uncertainty), indicating an onset of Cenozoic alkaline volcanism in the Marie Byrd Land Volcanic Province in latest Eocene time. Middle Oligocene (29-27 Ma) hawaiite volcaniclastic lithofacies at Mount Petras are interpreted as products of mixed magmatic (Strombolian style) and phreatomagmatic (Surtseyan style) subaerial eruptions. The four hawaiite outcrop areas exhibit characteristics of near-vent tuff cone environments. The near-vent deposits are located at different elevations and positions on Mount Petras and suggest four separate eruptive centres, with eruptions dated to between 28.59 ± 0.22 Ma and 27.18 ± 0.23 Ma. The mixed Surtseyan and Strombolian eruptions imply local or intermittent contact with external water, which we infer was derived from melting of a thin, local ice cap or ice and snow on slopes. The 29-27 Ma volcanic deposits at Mount Petras provide the oldest terrestrial evidence for glacial ice in Marie Byrd Land. The 29-27 Ma tuff cone deposits overlie an erosional unconformity, with > 400 m of topographic relief. The relatively high relief pre-volcanic environment is suggestive of ongoing erosion and is inconsistent with previous interpretations of a regional, low relief, early Cenozoic West Antarctic Erosion Surface.

How do you solve a problem like… missing data? Lessons from the PAin SoluTions In the Emergency Setting (PASTIES) trials

2019 ◽  
Vol 105 (1) ◽  
pp. 23-28
Author(s):  
J E Smith ◽  
S Creanor ◽  
M Rockett ◽  
P Ewings
Keyword(s):  
Missing Data ◽  
Final Analysis ◽  
Emergency Setting ◽  
Affect Studies ◽  
Pain Scores ◽  
Multiple Data ◽  
Data Points ◽  
Military Patients ◽  
Over Time

AbstractWhen studies measure the effect of a treatment longitudinally over time, multiple data points are generated, but are sometimes incomplete. This may affect studies in a range of different settings, including studies on military patients. When analysing the data from such a study, one of the challenges is how to deal with missing data points in the final analysis. This article describes the possible different ways of dealing with missing data points in such a context, and outlines some pragmatic methods used for handling missing pain scores in the recent PAin SoluTions In the Emergency Setting (PASTIES) trials.

Late Eocene – Early Miocene facies and stratigraphic development, Taranaki Basin, New Zealand: the transition to plate boundary tectonics during regional transgression

2019 ◽  
Vol 156 (10) ◽  
pp. 1751-1770 ◽  
Author(s):  
Dominic P. Strogen ◽  
Karen E. Higgs ◽  
Angela G. Griffin ◽  
Hugh E. G. Morgans
Keyword(s):  
New Zealand ◽  
Tectonic Setting ◽  
Plate Boundary ◽  
Late Eocene ◽  
Early Miocene ◽  
Fault System ◽  
Initial Development ◽  
Early Oligocene ◽  
Well Data ◽  
Latest Eocene

AbstractEight latest Eocene to earliest Miocene stratigraphic surfaces have been identified in petroleum well data from the Taranaki Basin, New Zealand. These surfaces define seven regional sedimentary packages, of variable thickness and lithofacies, forming a mixed siliciclastic–carbonate system. The evolving tectonic setting, particularly the initial development of the Australian–Pacific convergent margin, controlled geographic, stratigraphic and facies variability. This tectonic signal overprinted a regional transgressive trend that culminated in latest Oligocene times. The earliest influence of active compressional tectonics is reflected in the preservation of latest Eocene – Early Oligocene deepwater sediments in the northern Taranaki Basin. Thickness patterns for all mid Oligocene units onwards show a shift in sedimentation to the eastern Taranaki Basin, controlled by reverse movement on the Taranaki Fault System. This resulted in the deposition of a thick sedimentary wedge, initially of coarse clastic sediments, later carbonate dominated, in the foredeep close to the fault. In contrast, Oligocene active normal faulting in a small sub-basin in the south may represent the most northerly evidence for rifting in southern Zealandia, related to Emerald Basin formation. The Early Miocene period saw a return to clastic-dominated deposition, the onset of regional regression and the southward propagation of compressional tectonics.

Independence and generalizability in linguistics

Linguistics ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Bodo Winter ◽  
Martine Grice
Keyword(s):  
Data Structures ◽  
Mixed Models ◽  
Corpus Linguistics ◽  
Independent Data ◽  
Diverse Range ◽  
Quantitative Studies ◽  
Multiple Data ◽  
Data Points ◽  
Sources Of Variation ◽  
Multiple Languages

Abstract Quantitative studies in linguistics almost always involve data points that are related to each other, such as multiple data points from the same participant, multiple texts from the same book, author, genre, or register, or multiple languages from the same language family. Statistical procedures that fail to account for the relatedness of observations by assuming independence among units can lead to grossly misleading results if these sources of variation are ignored. As mixed effects models are increasingly used to analyze these non-independent data structures, it might appear that the problem of violating the independence assumption is solved. In this paper, we argue that it is necessary to re-open and widen the discussion about sources of variation that are being ignored, not only in statistical analyses, but also in the way studies are designed. Non-independence is not something that is “solved” by new statistical methods such as mixed models, but it is something that we continuously need to discuss as we apply new methods to an increasingly diverse range of linguistic datasets and corpora. In addition, our paper delivers something that is currently missing from statistical textbooks for linguists, which is an overview of non-independent data structures across different subfields of linguistics (corpus linguistics, typology, phonetics etc.), and how mixed models are used to deal with these structures.

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