Marine reptiles (Plesiosauria and Mosasauridae) from the Puskwaskau Formation (Santonian–Campanian), west-central Alberta

2014 ◽  
Vol 88 (1) ◽  
pp. 187-194 ◽  
Author(s):  
Phil R. Bell ◽  
Federico Fanti ◽  
Mark T. Mitchell ◽  
Philip J. Currie
Keyword(s):  
North America ◽  
High Latitude ◽  
Western Interior Seaway ◽  
Northern Canada ◽  
Marine Predators ◽  
The North ◽  
Marine Reptiles ◽  
West Central

Plesiosaurs and mosasaurs are identified from the Puskwaskau Formation of west-central Alberta, Canada. These deposits record the final stages during which the Western Interior Seaway remained open to the Boreal Sea to the North and therefore are important for determining the ranges of high-latitude marine reptiles. Polycotylid and elasmosaurid plesiosaurs shared these waters with russellosaurine (including plioplatecarpine) mosasaurs suggesting a diverse ecology of large-bodied marine predators occupied these high-latitude waters in the early Campanian. This locality, situated at 65°N paleolatitude, helps link the poorly known faunas from northern Canada with the better-known faunas from central and southern North America. Rare articulated material from the Puskwaskau Formation urges further investigation of this poorly explored unit.

Evidence for a second species of the ichthyosaur Platypterygius in North America: a new record from the Loon River Formation (Lower Cretaceous) of northwestern Canada

2006 ◽  
Vol 43 (9) ◽  
pp. 1291-1295 ◽  
Author(s):  
E E Maxwell ◽  
M W Caldwell
Keyword(s):  
North America ◽  
Northwest Territories ◽  
Lower Cretaceous ◽  
New Record ◽  
Taxonomic Diversity ◽  
Pectoral Girdle ◽  
Western Interior Seaway ◽  
Anterior Portion ◽  
Australian Species ◽  
Marine Reptiles

To date, all Cretaceous ichthyosaur material from North America has been referred to the species Platypterygius americanus. This species is generally identified based on skull and paddle morphology, but all non-diagnostic material from North America has been assigned to this species. A new Lower Cretaceous ichthyosaur from the Loon River Formation at Hay River, Northwest Territories, Canada, is described here. The specimen in question consists of the anterior portion of a large ichthyosaur, of which only the pectoral girdle is well preserved. It is assignable to Platypterygius, but is inconsistent with P. americanus based on paddle morphology. It shares most similarities with European and Australian species; unfortunately, it cannot be definitively assigned to any one taxon because of poor preservation of the skull. This specimen increases our knowledge of the diversity of North American Cretaceous ichthyosaurs, and suggests that the Cretaceous Western Interior Seaway was capable of sustaining a large taxonomic diversity of these marine reptiles, similar to the high numbers of Platypterygius species known from Europe.

scholarly journals Rapid waxing and waning of Beringian ice sheet reconcile glacial climate records from around North Pacific

2020 ◽  
Author(s):  
Zhongshi Zhang ◽  
Qing Yan ◽  
Ran Zhang ◽  
Florence Colleoni ◽  
Gilles Ramstein ◽  
...  
Keyword(s):  
North America ◽  
High Latitude ◽  
North Pacific ◽  
Ice Sheets ◽  
Ice Sheet ◽  
The North ◽  
Climate Records ◽  
Climate Evolution ◽  
Paleoclimate Records ◽  
Glacial Landforms

Abstract. Throughout the Pleistocene the Earth has experienced pronounced glacial-interglacial cycles, which have been debated for decades. One concept widely held is that during most glacials only the Laurentide-Eurasian ice sheets across North America and Northwest Eurasia became expansive, while Northeast Siberia-Beringia remained ice-sheet-free. However, the recognition of glacial landforms and deposits on Northeast Siberia-Beringia and off the Siberian continental shelf is beginning to call into question this paradigm. Here, we combine climate and ice sheet modelling with well-dated paleoclimate records from the mid-to-high latitude North Pacific to demonstrate the episodic occurrences of an ice sheet across Northeast Siberia-Beringia. Our simulations first show that the paleoclimate records are irreconcilable with the established paradigm of Laurentide-Eurasia-only ice sheets, and then reveal that a Beringian ice sheet over Northeast Siberia-Beringia causes feedbacks between atmosphere and ocean, the result of which better explains these climate records from around the North Pacific during the past four glacial-interglacial cycles. Our simulations propose an alternative scenario for NH ice sheet evolution, which involves the rapid waxing and waning of the Beringian ice sheet alongside the growth of the Laurentide-Eurasian ice sheets. The new scenario settles the long-standing discrepancies between the direct glacial evidence and the climate evolution from around the mid-to-high latitude North Pacific. It depicts a high complexity in glacial climates and has important implications for our understanding of the dispersal of prehistoric humans through Beringia into North America.

Growing Pacific Linkage with the Interannual Variability of North Atlantic Explosive Cyclogenesis

2021 ◽  
Author(s):  
Jacob John Stuivenvolt Allen ◽  
Simon S.-Y. Wang ◽  
Yoshimitsu Chikamoto ◽  
Jonathan D.D. Meyer ◽  
Zachary F. Johnson ◽  
...  
Keyword(s):  
North America ◽  
Interannual Variability ◽  
North Atlantic ◽  
High Latitude ◽  
East Coast ◽  
Wave Train ◽  
Baroclinic Instability ◽  
The North ◽  
Atmospheric Wave ◽  
The North Atlantic

Abstract Explosive cyclones (ECs), defined as developing extratropical cyclones that experience pressure drops of at least 24 hPa in 24 hours, are impactful weather events which occur along highly populated coastal regions in the eastern United States. These storms occur due to a combination of atmospheric and surface processes, such as jet stream intensification and latent heat release at the ocean surface. Even though previous literature has elucidated the role of these processes in EC formation, the sources of interannual variability that impact seasonal EC frequency are not well known. To analyze the sources of interannual variability, we track cases of ECs and dissect them into two spatial groups: those that formed near the east coast of North America (coastal) and those in the North Central Atlantic (high latitude). The frequency of high-latitude ECs is strongly correlated with the North Atlantic Oscillation, a well-known feature, whereas coastal EC frequency exhibits a growing relationship with an atmospheric wave-train emanating from the North Pacific in the last 30 years. This wave-train pattern of alternating high-and-low pressure resulted in resulted in heightened upper-level divergence and baroclinic instability along the east coast of North America. Using a coupled model experiment, we show that the tropical Pacific Ocean is the main driver of this atmospheric wave train and the subsequent enhancement seasonal baroclinic instability in the North Atlantic.

A new record of the pliosaurBrachauchenius lucasiWilliston, 1903 (Reptilia: Sauropterygia) of Turonian (Late Cretaceous) age, Morocco

2015 ◽  
Vol 153 (3) ◽  
pp. 449-459 ◽  
Author(s):  
D. ANGST ◽  
N. BARDET
Keyword(s):  
North America ◽  
South America ◽  
Late Cretaceous ◽  
North Africa ◽  
New Record ◽  
The Other ◽  
Western Interior Seaway ◽  
Marine Fauna ◽  
Marine Reptiles ◽  
Northern South America

AbstractThe site of Goulmima (south Morocco) is well known for its rich marine fauna of Turonian age (Late Cretaceous). It has yielded a large variety of invertebrates but also of vertebrate taxa, represented by actinopterygians and marine reptiles including Plesiosauria (Sauropterygia) and Mosasauroidea (Squamata). The Plesiosauria are known so far by two major clades of Plesiosauroidea: the Elasmosauridae (Libonectes atlasenseBuchy, 2005) and the Polycotylidae (Thililua longicollis, Bardet, Suberbiola & Jalil, 2003a;Manemergus angirostrisBuchy, Metayer & Frey, 2005). Here we describe a new specimen of plesiosaur found in the same outcrop, differing from those previously cited and belonging to the other large plesiosaur clade, the Pliosauroidea. Comparison of this specimen with other Plesiosauria shows that it belongs toBrachauchenius lucasiWilliston (1903), a species previously known only from the Cenomanian–Turonian stages of the Western Interior Seaway of North America and in the upper Barremian succession of northern South America (Colombia). The description of this species on a contemporaneous site of North Africa significantly expands its palaeobiogeographic distribution. This discovery confirms the affinities between marine faunas of the Western Interior Seaway and those of North Africa at this time, and also permits a better understanding of the palaeobiology of the Goulmima outcrop. A discussion about the systematical status ofPolyptychodonOwen, 1841 is also provided.

scholarly journals Winter Midlatitude Cold Anomalies Linked to North Atlantic Sea Ice and SST Anomalies: The Pivotal Role of the Potential Vorticity Gradient

2019 ◽  
Vol 32 (13) ◽  
pp. 3957-3981 ◽  
Author(s):  
Xiaodan Chen ◽  
Dehai Luo
Keyword(s):  
North America ◽  
North Atlantic ◽  
High Latitude ◽  
Large Scale ◽  
Northern Europe ◽  
The North ◽  
Sst Cooling ◽  
The North Atlantic ◽  
Large Scale Atmospheric Circulation ◽  
Pv Gradient

Abstract This study establishes a linkage between the North Atlantic sea ice concentration (SIC) or sea surface temperature (SST) and cold anomalies over northern Europe and North America through the Greenland blocking (GB) change. It is revealed that the magnitude of the meridional potential vorticity (PV) gradient in the North Atlantic mid- to high latitudes plays a key role in whether strong cold anomalies occur over the North America (NA) or northern Europe (NE) or both, while it is related to the SIC change observed over Baffin Bay, Davis Strait, and the Labrador Sea (BDL collectively) and the North Atlantic SST anomaly. When the midlatitude Atlantic SST is strongly warm or when the BDL SIC anomaly is largely positive, there is a corresponding large PV gradient over the North Atlantic. In this case, no intense cold anomalies are seen over NA due to less westward movement and the short lifetime of GB. Instead, a relatively strong cold anomaly appears over western and southern Europe. Its prior large-scale atmospheric circulation is the positive phase of the North Atlantic Oscillation (NAO). Moreover, strong cold anomalies can simultaneously occur over NA and NE only when the PV gradient is small under the influence of large SIC decline or intense mid- to high-latitude SST cooling across the Gulf Stream Extension. Its prior large-scale atmospheric circulation is a negative NAO phase. Daily composites show that strong cold anomalies over NA occur along the northwest–southeast direction in the presence of large SIC decline, whereas strong cold anomalies occur in NA midlatitudes even in the absence of large BDL SIC decline when mid- to high-latitude SST cooling is strong.

New Brontotheriidae (Mammalia, Perissodactyla) from the early and middle Eocene of Pakistan with implications for mammalian paleobiogeography

2011 ◽  
Vol 85 (4) ◽  
pp. 665-677 ◽  
Author(s):  
Pieter Missiaen ◽  
Gregg F. Gunnell ◽  
Philip D. Gingerich
Keyword(s):  
North America ◽  
High Latitude ◽  
Middle Eocene ◽  
Indian Subcontinent ◽  
Taxonomic Resolution ◽  
Early Eocene ◽  
Early Eocene Climatic Optimum ◽  
The North ◽  
Primitive Species ◽  
Subathu Formation

Brontotheriids are common in Eocene faunas of North America and Asia but are poorly known from the Indian subcontinent. Here we describe three new late early Eocene brontotheriids from Pakistan, found in the upper part of the upper Ghazij Formation and representing the oldest Asian brontotheres. Eotitanops pakistanensis n. sp. is a small, primitive species, Balochititanops haqi n. gen. n. sp. is slightly larger and more derived, and fragmentary specimens identified as cf. Balochititanops sp. appear to represent a third, larger taxon.Improved knowledge of early brontotheres from North America permits better taxonomic resolution of some middle Eocene brontothere remains from Pakistan. ‘Eotitanops’ dayi from the Kuldana Formation is shown to be closer to Palaeosyops and is renamed Palaeosyops dayi n. comb. A new astragalus from the Baska Formation probably represents Pakotitanops latidentatus. A previously described humerus and a new calcaneum, both from the Subathu Formation, are tentatively referred to Mulkrajanops moghliensis.Phylogenetic interpretation suggests that Eotitanops pakistanensis is as primitive as the North American species of this basal brontothere genus, and also, within the limits of stratigraphic resolution, Eotitanops appeared on both continents at the same time. The origin of brontotheres is therefore equally likely to have been in Asia or in North America. The presence of the primitive brontotheres Eotitanops and Palaeosyops in Indo-Pakistan and North America indicates faunal exchange, almost certainly through Asia, although the direction of dispersal cannot be determined. The postulated high-latitude exchange coincides with a warm interval known as the Early Eocene Climatic Optimum.

Экологическое испытание гибрида огурца F1 Энеж 21 в открытом грунте

2018 ◽  
Author(s):  
L.A. Chistyakova ◽  
O.V. Baklanova ◽  
E.L. Makarova ◽  
Yu.V. Bortsova
Keyword(s):  
Russian Federation ◽  
High Potential ◽  
Moscow Region ◽  
North West ◽  
The North ◽  
Pickling Cucumber ◽  
West Central ◽  
Open Ground ◽  
Chuvash Republic ◽  
The Russian Federation

Приведены результаты испытания нового перспективного партенокарпического гибрида огурца корнишонного типа F1 Энеж 21, созданного селекционерами агрохолдинга «Поиск», в условиях открытого грунта в Северо-Западном, Центральном и Волго-Вятском регионах Российской Федерации: Костромская, Ярославская, Московская, Рязанская, Тульская область и Чувашская Республика. Высокие потенциальные возможности и адаптационные свойства гибрида F1 Энеж 21 наиболее значимо проявляются в Московской области (63,8 т/га), Чувашской Республике (39,4 т/га) и Рязанской области (31,2 т/га).The article presents the results of testing a new promising parthenocarpic pickling cucumber hybrid F1 Enezh 21, selected by the breedrs of the Agricultural holding «Poisk» in conditions of open ground in the North-West, Central and Volga-Vyatka regions of the Russian Federation: Kostroma, Yaroslavl, Moscow, Ryazan, Tula regions and the Chuvash Republic. The high potential and adaptation characteristic of the F1 Enezh 21 hybrid are most significantly presented in condition of the Moscow region (63.8 t / ha), the Chuvash Republic (39.4 t / ha) and the Ryazan region (31.2 t / ha).

Political orientation and moral foundations

2019 ◽  
Vol 118 (11) ◽  
pp. 365-371
Author(s):  
J Dorasamy ◽  
Mr Jirushlan Dorasamy
Keyword(s):  
South Africa ◽  
North America ◽  
American Studies ◽  
Political Orientation ◽  
The Political ◽  
Moral Foundations ◽  
Open Approach ◽  
Online Questionnaire ◽  
Moral Foundation ◽  
The North

Studies, especially in the North America, have shown a relationship between political orientation and moralfoundation. This study investigated whether moral judgements differ from the political orientation of participantsin South Africa moral judgment and the extent to which moral foundations are influenced by politicalorientation.Further, the study investigated the possibility of similar patterns with the North AmericanConservative-Liberal spectrum and the moral foundation. There were 300participants, 78 males and 222 females,who completed an online questionnaire relating to moral foundation and political orientation. The results partiallysupported the hypothesis relating to Liberal and Conservative orientation in South Africa. Further, this studypartially predicted the Liberal-Conservative orientation with patterns in the moral foundation, whilst showingsimilar findings to the North American studies. A growing rate of a neutral/moderate society is evidenced in SouthAfrica and abroad, thereby showing the emergence of a more open approach to both a political and generalstance.”””

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