An ammonite zonation for the Lower Jurassic of Canada and the United States: the Pliensbachian

1988 ◽  
Vol 25 (9) ◽  
pp. 1503-1523 ◽  
Author(s):  
Paul L. Smith ◽  
Howard W. Tipper ◽  
David G. Taylor ◽  
Jean Guex
Keyword(s):  
North America ◽  
North American ◽  
Lower Boundary ◽  
The United States ◽  
Lower Jurassic ◽  
Queen Charlotte Islands ◽  
The North ◽  
East Pacific ◽  
Reference Sections ◽  
Northeast Asian

This is the first in a series of papers intended to establish a Lower Jurassic ammonite zonation that takes into account the biostratigraphic and biogeographic peculiarities of the North American succession. Its development has been spurred by the need for high-resolution correlation between allochthonous terranes and the need for a standard to which microfossil sequences may be coupled.In North America the lower boundary of the Pliensbachian is drawn above the last echioceratids. The lower Pliensbachian is divided into, in ascending order, the Imlayi, Whiteavesi, and Freboldi zones; the upper Pliensbachian, into the Kunae and Carlottense zones. The Fannin Bay section in the Queen Charlotte Islands is designated the stratotype for the Whiteavesi, Freboldi, and Kunae zones; ideal stratotypes for the Imlayi and Carlottense zones are not presently known. Reference sections former illustrating the faunal associations that characterize all the zones are designated in western Nevada (the Sunrise Formation), northeastern Oregon (the Hurwal Formation), and northern British Columbia (the Spatsizi Group and Takwahoni Formation).The Polymorphitidae and Eoderoceratidae furnish the most important zonal indicators for the lower Pliensbachian; Oxynoticeratidae (Fanninoceras) and Hildoceratidae, for the upper Pliensbachian. Pseudoskirroceras imlayi and Acanthopleuroceras whiteavesi are described as new species. The presence of amaltheids in the northern parts of the allochthonous terranes permits a comparison with the northwest European succession at this level. Furthermore, the association in North America of typically east Pacific, Mediterranean, and northeast Asian species, as well as northwest European forms, emphasizes the critical importance of the North American Pliensbachian in achieving global correlations.

An ammonite zonation for the Toarcian (Lower Jurassic) of the North American Cordillera

1994 ◽  
Vol 31 (6) ◽  
pp. 919-942 ◽  
Author(s):  
Giselle K. Jakobs ◽  
Paul L. Smith ◽  
Howard W. Tipper
Keyword(s):  
New Species ◽  
North America ◽  
North American ◽  
Lower Boundary ◽  
Lower Jurassic ◽  
North American Cordillera ◽  
Queen Charlotte Islands ◽  
The North ◽  
Reference Sections ◽  
A New Species

This is the second in a series of papers intended to establish a Lower Jurassic ammonite zonation that takes into account the biostratigraphic and biogeographic peculiarities of the North American succession. In North America the lower boundary of the Toarcian is drawn at the first appearance of Dactylioceras above the last occurrence of Amaltheus and Fanninoceras. The lower Toarcian is represented by the Kanense Zone; the middle Toarcian by the Planulata and Crassicosta zones; and the upper Toarcian by the Hillebrandti and Yakounensis zones. Section 5 on the Yakoun River in the Queen Charlotte Islands is designated the stratotype for the Planulata, Crassicosta, and Hillebrandti zones; section 3 on the Yakoun River is designated the stratotype for the Yakounensis Zone; an ideal stratotype for the Kanense Zone is not presently known. Reference sections further illustrating the faunal associations that characterize the zones are designated in eastern Oregon (Snowshoe Formation) and northern British Columbia (Spatsizi Group). The Dactylioceratidae, Harpoceratinae, and Hildoceratinae provide the most important zonal indicators for the lower Toarcian; Dactylioceratidae, Phymatoceratinae, and Bouleiceratinae for the middle Toarcian; and Phymatoceratinae, Grammoceratinae, and Hammatoceratinae for the upper Toarcian. Phymatoceras hillebrandti is described as a new species.

scholarly journals Progress in Diagnosing Primary Ciliary Dyskinesia: The North American Perspective

Diagnostics ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1278
Author(s):  
Michael Glenn O’Connor ◽  
Amjad Horani ◽  
Adam J. Shapiro
Keyword(s):  
Genetic Testing ◽  
North America ◽  
North American ◽  
Primary Ciliary Dyskinesia ◽  
Clinical Phenotype ◽  
The United States ◽  
Diagnostic Process ◽  
The North ◽  
Diagnostic Guideline ◽  
Ciliary Dyskinesia

Primary Ciliary Dyskinesia (PCD) is a rare, under-recognized disease that affects respiratory ciliary function, resulting in chronic oto-sino-pulmonary disease. The PCD clinical phenotype overlaps with other common respiratory conditions and no single diagnostic test detects all forms of PCD. In 2018, PCD experts collaborated with the American Thoracic Society (ATS) to create a clinical diagnostic guideline for patients across North America, specifically considering the local resources and limitations for PCD diagnosis in the United States and Canada. Nasal nitric oxide (nNO) testing is recommended for first-line testing in patients ≥5 years old with a compatible clinical phenotype; however, all low nNO values require confirmation with genetic testing or ciliary electron micrograph (EM) analysis. Furthermore, these guidelines recognize that not all North American patients have access to nNO testing and isolated genetic testing is appropriate in cases with strong clinical PCD phenotypes. For unresolved diagnostic cases, referral to a PCD Foundation accredited center is recommended. The purpose of this narrative review is to provide insight on the North American PCD diagnostic process, to enhance the understanding of and adherence to current guidelines, and to promote collaboration with diagnostic pathways used outside of North America.

Knotweed Management Strategies in North America with the Advent of Widespread Hybrid Bohemian Knotweed, Regional Differences, and the Potential for Biocontrol Via the Psyllid Aphalara itadori Shinji

2016 ◽  
Vol 9 (1) ◽  
pp. 60-70 ◽  
Author(s):  
David R. Clements ◽  
Todd Larsen ◽  
Jennifer Grenz
Keyword(s):  
Biological Control ◽  
Invasive Species ◽  
Genetic Variation ◽  
North America ◽  
North American ◽  
Regional Differences ◽  
The United States ◽  
The North ◽  
Variable Nature ◽  
Available Resources

AbstractInvasive species with distributions that encompass much of the North American environment often demand a range of management approaches, for several key reasons. Firstly, the North American environment includes a large number of highly variable habitats in terms of climatic, edaphic, and landscape features. Secondly, these regional habitat differences are accentuated by jurisdictions within Canada and the United States, whereby approaches and available resources differ at local, regional, and national scales. Another important consideration is whether an invasive species or complex also possesses genetic variation. All three of these factors render the knotweed complex in North America a highly variable target for management. In this paper we review existing knowledge of the variable nature of knotweed species (Fallopia japonica (Houtt.) Ronse Decr., Fallopia sachalinensis (F. Schmidt ex Maxim) Ronse Decr., and Fallopia × bohemica, (Chrtek and Chrtková) J. P. Bailey in North America, and evaluate how herbicidal, mechanical and biological control measures must account for this genetic variation, as well as accounting for regional differences and the potential northward expansion of knotweed under climate change. The imminent release of the psyllid, Aphalara itadori Shinji as a biological control agent in North America must also navigate regional and genetic differences. Prior European experience dealing with the three knotweed species should prove useful, but additional research is needed to meet the emerging challenge posed by F. × bohemica in North America, including the possibility of glyphosate resistance. Managers also face challenges associated with posttreatment restoration measures. Furthermore, disparities in resources available to address knotweed management across the continent need to be addressed to contain the rapid spread of this highly persistent and adaptable species. Linking practitioners dealing with knotweed “on the ground” with academic research is a crucial step in the process of marshalling all available resources to reduce the rapidly spreading populations of knotweed.

New occurrences of Leukadiella and Paroniceras (Ammonoidea) from the Toarcian (Lower Jurassic) of the Canadian Cordillera

1995 ◽  
Vol 69 (1) ◽  
pp. 89-98 ◽  
Author(s):  
G. K. Jakobs
Keyword(s):  
North America ◽  
Mediterranean Region ◽  
Lower Jurassic ◽  
Canadian Cordillera ◽  
Rare Occurrence ◽  
Western Tethys ◽  
North American Cordillera ◽  
Queen Charlotte Islands ◽  
The North ◽  
New Occurrences

Previous studies of the Toarcian of the North American Cordillera have mentioned the rare occurrence of Paroniceras in the Queen Charlotte Islands. Recent work has identified the presence of Leukadiella in the Middle Toarcian of the Queen Charlotte Islands, the Spatsizi area, and the Hazelton area. They occur with Rarenodia planulata, Peronoceras pacificum, Peronoceras verticosum, and Phymatoceras cf. P. pseudoerbaense. The Leukadiella specimens are well preserved and generally larger than those found in the Mediterranean region. Taxa present in North America include Paroniceras sternale, Leukadiella ionica, Leukadiella amuratica, Leukadiella aff. L. helenae, and Leukadiella aff. L. ionica. Morphologically Leukadiella is closely related to such genera as Hildaites and Hildoceras and is more suitably placed within the subfamily Hildoceratinae rather than the Bouleiceratinae. The distribution of Leukadiella and Paroniceras indicates the influence of the Hispanic Corridor linking western Tethys and the eastern Pacific during the Middle Toarcian.

Lower Jurassic Amaltheidae (Ammonitina) in North America: paleobiogeography and tectonic implications

2001 ◽  
Vol 38 (10) ◽  
pp. 1439-1449 ◽  
Author(s):  
Paul L Smith ◽  
Howard W Tipper ◽  
David M Ham
Keyword(s):  
North America ◽  
North Atlantic ◽  
Lower Jurassic ◽  
The Arctic ◽  
Longitudinal Displacement ◽  
The North ◽  
East Pacific ◽  
Northwest Europe ◽  
Dispersal Route ◽  
North American Craton

The amaltheids are restricted temporally to the late Pliensbachian and geographically to the northern part of the northern hemisphere. Amaltheus stokesi is the only species that occurs in all areas of North America where amaltheids are found. The craton north of the Canada–U.S.A. border yields the most diverse amaltheid fauna, including six of the seven taxa known in North America. On Quesnellia and Stikinia, there are no endemic amaltheids, and diversity is low; A. stokesi increases in abundance northwards where, in Stikinia, A. margaritatus makes rare appearances. Wrangellia, with its rich Pliensbachian Tethyan and east Pacific faunas, is almost devoid of amaltheids, but its amaltheid fauna does include two specimens of A. viligaensis, an eastern Russian species that is unknown elsewhere in North America. Cratonal amaltheid faunas have more in common with those of northwest Europe than eastern Eurasia, suggesting that the Arctic and northern North Atlantic constituted the main dispersal route. Paleobiogeographic patterns on the major allochthonous terranes argue against terrane rotation and in support of post-Pliensbachian northward displacement relative to the North American craton. In addition, the presence of western Pacific faunal elements on Wrangellia suggests a more significant longitudinal displacement relative to the craton for this terrane compared to that for Quesnellia and Stikinia. The Chilliwack terrane of southwestern British Columbia is a Pliensbachian paleobiogeographic anomaly.

scholarly journals The North American Lightning Detection Network (NALDN)—Analysis of Flash Data: 2001–09

2011 ◽  
Vol 139 (5) ◽  
pp. 1305-1322 ◽  
Author(s):  
Richard E. Orville ◽  
Gary R. Huffines ◽  
William R. Burrows ◽  
Kenneth L. Cummins
Keyword(s):  
United States ◽  
North America ◽  
North American ◽  
The United States ◽  
The North ◽  
Lightning Detection ◽  
Geographical Regions ◽  
Positive Peak ◽  
The U.S ◽  
Cg Lightning

Cloud-to-ground (CG) lightning data have been analyzed for the years 2001–09 for North America, which includes Alaska, Canada, and the lower 48 U.S. states. Flashes recorded within the North American Lightning Detection Network (NALDN) are examined. No corrections for detection efficiency variability are made over the 9 yr of the dataset or over the large geographical area comprising North America. There were network changes in the NALDN during the 9 yr, but these changes have not been corrected for nor have the recorded data been altered in any way with the exception that all positive lightning reports with peak currents less than 15 kA have been deleted. Thus, the reader should be aware that secular changes are not just climatological in nature. All data were analyzed with a spatial resolution of 20 km. The analyses presented in this work provide a synoptic view of the interannual variability of lightning observations in North America, including the impacts of physical changes in the network during the 9 yr of study. These data complement and extend previous analyses that evaluate the U.S. NLDN during periods of upgrade. The total (negative and positive) flashes for ground flash density, the percentage of positive lightning, and the positive flash density have been analyzed. Furthermore, the negative and positive first stroke peak currents and the flash multiplicity have been examined. The highest flash densities in Canada are along the U.S.–Canadian border (1–2 flashes per square kilometer) and in the United States along the Gulf of Mexico coast from Texas through Florida (exceeding 14 flashes per square kilometer in Florida). The Gulf Stream is “outlined” by higher flash densities off the east coast of the United States. Maximum annual positive flash densities in Canada range primarily from 0.01 to 0.3 flashes per square kilometer, and in the United States to over 0.5 flashes per square kilometer in the Midwest and in the states of Louisiana and Mississippi. The annual percentage of positive lightning to ground varies from less than 2% over Florida to values exceeding 25% off the West Coast, Alaska, and the Yukon. A localized maximum in the percentage of positive lightning in the NALDN occurs in Manitoba and western Ontario, just north of North Dakota and Minnesota. When averaged over North America, first stroke negative median peak currents range from 19.8 kA in 2001 to 16.0 kA in 2009 and for all years, average 16.1 kA. First stroke positive median peak currents range from a high of 29.0 kA in 2008 and 2009 to a low of 23.3 kA in 2003 with a median of 25.7 kA for all years. There is a relatively sharp transition from low to high median negative peak currents along the Gulf and Atlantic coasts of the United States. No sharp transitions are observed for the median positive peak currents. Relatively lower positive peak currents occur throughout the southeastern United States. The highest values of mean negative multiplicity exceed 3.0 strokes per flash in the NALDN with some variation over the 9 yr. Lower values of mean negative multiplicity occur in the western United States. Positive flash mean multiplicity is slightly higher than 1.1, with the highest values of 1.7 observed in the southwestern states. As has been noted in prior research, CG lightning has significant variations from storm to storm as well as between geographical regions and/or seasons and, consequently, a single distribution for any lightning parameter, such as multiplicity or peak current, may not be sufficient to represent or describe the parameter.

scholarly journals Economic costs of biological invasions within North America

NeoBiota ◽  
2021 ◽  
Vol 67 ◽  
pp. 485-510
Author(s):  
Robert Crystal-Ornelas ◽  
Emma J. Hudgins ◽  
Ross N. Cuthbert ◽  
Phillip J. Haubrock ◽  
Jean Fantle-Lepczyk ◽  
...  
Keyword(s):  
Invasive Species ◽  
North America ◽  
North American ◽  
Research Effort ◽  
The United States ◽  
Greater Antilles ◽  
Economic Costs ◽  
The North ◽  
Species Invasions ◽  
American Economy

Invasive species can have severe impacts on ecosystems, economies, and human health. Though the economic impacts of invasions provide important foundations for management and policy, up-to-date syntheses of these impacts are lacking. To produce the most comprehensive estimate of invasive species costs within North America (including the Greater Antilles) to date, we synthesized economic impact data from the recently published InvaCost database. Here, we report that invasions have cost the North American economy at least US$ 1.26 trillion between 1960 and 2017. Economic costs have climbed over recent decades, averaging US$ 2 billion per year in the early 1960s to over US$ 26 billion per year in the 2010s. Of the countries within North America, the United States (US) had the highest recorded costs, even after controlling for research effort within each country ($5.81 billion per cost source in the US). Of the taxa and habitats that could be classified in our database, invasive vertebrates were associated with the greatest costs, with terrestrial habitats incurring the highest monetary impacts. In particular, invasive species cumulatively (from 1960–2017) cost the agriculture and forestry sectors US$ 527.07 billion and US$ 34.93 billion, respectively. Reporting issues (e.g., data quality or taxonomic granularity) prevented us from synthesizing data from all available studies. Furthermore, very few of the known invasive species in North America had reported economic costs. Therefore, while the costs to the North American economy are massive, our US$ 1.26 trillion estimate is likely very conservative. Accordingly, expanded and more rigorous economic cost reports are necessary to provide more comprehensive invasion impact estimates, and then support data-based management decisions and actions towards species invasions.

scholarly journals THE EFFECT OF THE GLACIAL EPOCH UPON THE DISTRIBUTION OF INSECTS IN NORTH AMERICA

1875 ◽  
Vol 7 (9) ◽  
pp. 164-167
Author(s):  
Aug. R. Grote
Keyword(s):  
United States ◽  
North America ◽  
North American ◽  
The United States ◽  
American Continent ◽  
North American Continent ◽  
The North ◽  
Glacial Epoch

From the condition of an hypothesis the glacial epoch has been elevated into that of a theory by the explanations it has afforded to a certain class of geological phenomena. The present paper endeavors to show that certain zoological facts are consistent with the presence, during past times, of a vast progressive field of ice, which, in its movement from north to south, gradually extended over large portions of the North American continent. These facts, in the present instance, are furnished by a study of our Lepidoptera, or certain kinds of butterflies and moths now inhabiting the United States and adjacent territories.

Lyell on the Geological Similarity of North America and Europe

1982 ◽  
Vol 1 (1) ◽  
pp. 45-47
Author(s):  
Leonard Wilson
Keyword(s):  
North America ◽  
Coastal Plain ◽  
North American ◽  
The United States ◽  
Atlantic Coastal Plain ◽  
Fossil Plants ◽  
Land Area ◽  
The North ◽  
The Difference ◽  
Atlantic Coastal

During his travels in America in 1841-1842 and 1845-1846, Charles Lyell was impressed by the difference of the living flora and fauna of North America from those of Europe. The fossil shells of the Cretaceous strata of New Jersey and of the Tertiary formations of the Atlantic Coastal Plain of the United States showed that North America had also constituted a separate biological region during the Cretaceous and throughout the Tertiary. By contrast, the fossil plants of North American coal formations were so closely similar to those of Europe that Lyell concluded that during the Carboniferous, Europe and North America must have formed a continuous land area. As evidence of a former land connection between North America and Europe, Lyell observed that the distribution of sediments among the strata of the Appalachians indicated that the Carboniferous strata of North America had been derived from land lying to the East — where the Atlantic Ocean now is. Similarly, the North American Silurian and other Paleozoic systems contained fossils similar to those of Europe, and their sediments were so distributed as to suggest that they had been derived from land lying to the East. Lyell pointed out the ancient uniformity of European and American fossil life, without being able to explain it.

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