A Remarkable Array: Species Diversity in the United States

2000 ◽  
Author(s):  
Bruce A. Stein ◽  
Larry E. Morse
Keyword(s):  
United States ◽  
North America ◽  
Sea Level ◽  
Eastern China ◽  
The United States ◽  
The Other ◽  
Death Valley ◽  
The Arctic ◽  
Blue Ridge Mountains ◽  
Little Tennessee River

The Carolina hemlock (Tsuga caroliniana) survives in just a few rocky streambeds along the lower slopes of the Blue Ridge Mountains. Other species of hemlock abound across the United States, but none bear a close resemblance to this particular tree. The closest relatives of the Carolina hemlock, in fact, survive in only one other forest on Earth, some 7,000 miles away in Hubei province of eastern China. The forests of eastern Asia and eastern North America are so similar that if you were suddenly transported from one to the other, you would be hard-pressed to tell them apart. In the swift mountain streams rushing past these seemingly displaced hemlocks live a number of small, colorful fish known as darters. Darters are found only in North America and have evolved into a prolific variety of fishes. Up to 175 species inhabit U.S. waters, including the famous snail darter (Percina tanasi), which brought endangered species issues to the fore when it held up construction of the Tellico Dam on the Little Tennessee River. How is it that these two organisms, hemlock and darter, one with its closest relatives on the other side of the globe and the other found nowhere else in the world, came to be living side by side? Just how many plants and animals share the piece of Earth that we know as the United States of America? Why these and not others? These are central questions for understanding the diversity of the nation’s living resources. The United States encompasses an enormous piece of geography. With more than 3.5 million square miles of land and 12,000 miles of coastline, it is the fourth largest country on Earth, surpassed only by Russia, Canada, and China. The nation spans nearly a third of the globe, extending more than 120 degrees of longitude from eastern Maine to the tip of the Aleutian chain, and 50 degrees in latitude from Point Barrow above the Arctic Circle to the southern tip of Hawaii below the tropic of Cancer. This expanse of terrain includes an exceptional variety of topographic features, from Death Valley at 282 feet below sea level to Mt. McKinley at 20,320 feet above sea level.

The rise and fall of late Paleozoic trilobites of the United States

1999 ◽  
Vol 73 (2) ◽  
pp. 164-175 ◽  
Author(s):  
David K. Brezinski
Keyword(s):  
United States ◽  
North America ◽  
Sea Level ◽  
Adaptive Radiation ◽  
The United States ◽  
Upper Permian ◽  
Late Paleozoic ◽  
Lower Permian ◽  
Stage 4 ◽  
Stage 1

Based on range data and generic composition, four stages of evolution are recognized for late Paleozoic trilobites of the contiguous United States. Stage 1 occurs in the Lower Mississippian (Kinderhookian-Osagean) and is characterized by a generically diverse association of short-ranging, stenotopic species that are strongly provincial. Stage 2 species are present in the Upper Mississippian and consist of a single, eurytopic, pandemic genus, Paladin. Species of Stage 2 are much longer-ranging than those of Stage 1, and some species may have persisted for as long as 12 m.y. Stage 3 is present within Pennsylvanian and Lower Permian strata and consists initially of the eurytopic, endemic genera Sevillia and Ameura as well as the pandemic genus Ditomopyge. During the middle Pennsylvanian the very long-ranging species Ameura missouriensis and Ditomopyge scitula survived for more than 20 m.y. During the late Pennsylvanian and early Permian, a number of pandemic genera appear to have immigrated into what is now North America. Stage 4 is restricted to the Upper Permian (late Leonardian-Guadalupian) strata and is characterized by short-ranging, stenotopic, provincial genera.The main causal factor controlling the four-stage evolution of late Paleozoic trilobites of the United States is interpreted to be eustacy. Whereas Stage 1 represents an adaptive radiation developed during the Lower Mississippian inundation of North America by the Kaskaskia Sequence, Stage 2 is present in strata deposited during the regression of the Kaskaskia sea. Stage 3 was formed during the transgression and stillstand of the Absaroka Sequence and, although initially endemic, Stage 3 faunas are strongly pandemic in the end when oceanic circulation patterns were at a maximum. A mid-Leonardian sea-level drop caused the extinction of Stage 3 fauna. Sea-level rise near the end of the Leonardian and into the Guadalupian created an adaptive radiation of stentopic species of Stage 4 that quickly became extinct with the latest Permian regression.

Some Economic Aspects of the Brain Drain

1979 ◽  
Vol 9 (4) ◽  
pp. 7-14
Author(s):  
Harry G. Johnson
Keyword(s):  
United States ◽  
North America ◽  
Brain Drain ◽  
The United States ◽  
The Other ◽  
Economic Aspects ◽  
National State ◽  
The One ◽  
Professional People ◽  
The Brain

The concept of “brain drain” is in its origins a nationalistic concept, by which is meant a concept that visualizes economic and cultural welfare in terms of the welfare of the residents of a national state or region, viewed as a totality, and excludes from consideration both the welfare of people born in that region who choose to leave it, and the welfare of the outside world in general. Moreover, though the available statistics are far from adequate on this point, there is generally assumed to be a net flow of trained professional people from the former colonial territories to the ex-imperial European nations, and from Europe and elsewhere to North America and particularly the United States. The concept thus lends itself easily to the expression of anti-colonial sentiments on the one hand, and anti-American sentiments on the other. The expression of such sentiments can be dignified by the presentation of brain drain as a serious economic and cultural problem, by relying on nationalistic sentiments and assumptions and ignoring the principles of economics—especially the principle that in every transaction there is both a demand and a supply—or by elevating certain theoretical economic possibilities into presumed hard facts.

Introduction: Diaspora, Performance, and National Affiliations in North America

2003 ◽  
Vol 28 (3) ◽  
pp. 259-266 ◽  
Author(s):  
LOREN KRUGER
Keyword(s):  
United States ◽  
New York ◽  
North America ◽  
Host Country ◽  
Home Country ◽  
South Asians ◽  
The United States ◽  
The Other ◽  
Cantonese Opera ◽  
The One

Although current theories of diaspora argue for a break between an older irrevocable migration from one nation to another and a new transnational movement between host country and birthplace, research on nineteenth- as well as twentieth-century North America demonstrates that earlier migration also had a transnational dimension. The cultural consequences of this two-way traffic include syncretic performance forms, institutions, and audiences, whose legitimacy depended on engagement with but not total assimilation in local conventions and on the mobilization of touristic nostalgia in, say, Cantonese opera in California or Bavarian-American musicals in New York, to appeal to nativist and immigrant consumers. Today, syncretic theatre of diaspora is complicated on the one hand by a theatre of diasporic residence, in which immigrants dramatize inherited conflicts in the host country, such as Québécois separatism in Canada, along with problems of migrants, among them South Asians, and on the other by a theatre of non-residence, touring companies bringing theatre from the home country, say India, to ‘non-resident Indians’ and local audiences in the United States.

On Sea Level Variability and Trends in United States Coastal Waters and Relationships with Climate Factors

2015 ◽  
Vol 07 (01n02) ◽  
pp. 1550005 ◽  
Author(s):  
Leonard J. Pietrafesa ◽  
Shaowu Bao ◽  
Tingzhuang Yan ◽  
Michael Slattery ◽  
Paul T. Gayes
Keyword(s):  
United States ◽  
Sea Level Rise ◽  
Sea Level ◽  
Gulf Stream ◽  
The United States ◽  
The Arctic ◽  
Climate Factors ◽  
Sea Level Variability ◽  
Mean Sea Level ◽  
And Sea Level

Significant portions of the United States (U.S.) property, commerce and ecosystem assets are located at or near the coast, making them vulnerable to sea level variability and change, especially relative rises. Although global mean sea level (MSL) and sea level rise (SLR) are fundamental considerations, regional mean sea level (RSL) variability along the boundaries of U.S. along the two ocean basins are critical, particularly if the amplitudes of seasonal to annual to inter-annual variability is high. Of interest is that the conventional wisdom of the U.S. agencies, the National Aeronautics and Space Administration (NASA) and the National Oceanic and Atmospheric Administration (NOAA) which both contend that the sources of sea level rise are related principally to heat absorption and release by the ocean(s) to the atmosphere and vice versa, and by Polar glacier melting and freshwater input into the ocean(s). While these phenomena are of great importance to SLR and sea level variability (SLV), we assess a suite of climate factors and the Gulf Stream, for evidence of correlations and thus possible influences; though causality is beyond the scope of this study. In this study, climate factors related to oceanic and atmospheric heat purveyors and reservoirs are analyzed and assessed for possible correlations with sea level variability and overall trends on actionable scales (localized as opposed to global scale). The results confirm that oceanic and atmospheric temperature variability and the disposition of heat accumulation or the lack thereof, are important players in sea level variability and rise, but also that the Atlantic Multi-Decadal Oscillation, the El Niño-Southern Oscillation, the Pacific Decadal Oscillation, the Arctic Oscillation, the Quasi-Biennial Oscillation, the North Atlantic Oscillation, Solar Irradiance, the Western Boundary Current-Gulf Stream, and other climate factors, can have strong correlative and perhaps even causal, modulating effects on the monthly to seasonal to annual to inter-annual to decadal to multi-decadal sea level variability at the community level.

Launching Canadian Confederation: Means to Ends, 1836–1864

1984 ◽  
Vol 27 (3) ◽  
pp. 575-602 ◽  
Author(s):  
Ged Martin
Keyword(s):  
United States ◽  
North America ◽  
Nation Building ◽  
The United States ◽  
The Other ◽  
Founding Fathers ◽  
Victoria Falls

Canadian Confederation took shape at a conference at Charlottetown in September 1864, was designed in detail at the Quebec conference in October 1864 and revised into final form in London in 1866–7. The sequence of conferences forms part of the stately tread of Canadian nationhood, and provides a counterpart to the Annapolis and Philadelphia conventions which originated the other great nation of North America, just as the Fathers of Confederation echo the Founding Fathers of the United States. Subsequent meetings in other cities were to reinforce the aura of the nation-building conference, through Sydney, Melbourne, Adelaide and Durban to the less resounding triumphs of Montego Bay and Victoria Falls. Intercolonial unions, it seemed, were formed by calling conferences. From this assumption it could be deduced as a corollary that if no conference was called, there was no interest in intercolonial union. In Canada, the preservation of the Province House at Charlottetown as ‘the cradle of Confederation’ is a gesture to national feeling, but the mystique thus fostered risks creating historical distortion.

scholarly journals Dynamics, Variability, and Change in Seasonal Precipitation Reconstructions for North America

2020 ◽  
Vol 33 (8) ◽  
pp. 3173-3195 ◽  
Author(s):  
David W. Stahle ◽  
Edward R. Cook ◽  
Dorian J. Burnette ◽  
Max C. A. Torbenson ◽  
Ian M. Howard ◽  
...  
Keyword(s):  
United States ◽  
North America ◽  
Spatial Patterns ◽  
North American ◽  
Arctic Oscillation ◽  
Warm Season ◽  
The United States ◽  
The Arctic ◽  
Seasonal Precipitation ◽  
The Arctic Oscillation

AbstractCool- and warm-season precipitation totals have been reconstructed on a gridded basis for North America using 439 tree-ring chronologies correlated with December–April totals and 547 different chronologies correlated with May–July totals. These discrete seasonal chronologies are not significantly correlated with the alternate season; the December–April reconstructions are skillful over most of the southern and western United States and north-central Mexico, and the May–July estimates have skill over most of the United States, southwestern Canada, and northeastern Mexico. Both the strong continent-wide El Niño–Southern Oscillation (ENSO) signal embedded in the cool-season reconstructions and the Arctic Oscillation signal registered by the warm-season estimates faithfully reproduce the sign, intensity, and spatial patterns of these ocean–atmospheric influences on North American precipitation as recorded with instrumental data. The reconstructions are included in the North American Seasonal Precipitation Atlas (NASPA) and provide insight into decadal droughts and pluvials. They indicate that the sixteenth-century megadrought, the most severe and sustained North American drought of the past 500 years, was the combined result of three distinct seasonal droughts, each bearing unique spatial patterns potentially associated with seasonal forcing from ENSO, the Arctic Oscillation, and the Atlantic multidecadal oscillation. Significant 200–500-yr-long trends toward increased precipitation have been detected in the cool- and warm-season reconstructions for eastern North America. These seasonal precipitation changes appear to be part of the positive moisture trend measured in other paleoclimate proxies for the eastern area that began as a result of natural forcing before the industrial revolution and may have recently been enhanced by anthropogenic climate change.

scholarly journals Hophornbeam copperleaf (Acalypha ostryifolia Riddell)

2020 ◽  
Vol 34 (2) ◽  
pp. 305-307
Author(s):  
Lynn M. Sosnoskie ◽  
Robert M. Hayes ◽  
Lawrence E. Steckel
Keyword(s):  
United States ◽  
North America ◽  
The United States ◽  
The Arctic ◽  
Cosmopolitan Distribution ◽  
Plant Parts ◽  
Vegetative Plant ◽  
Dicot Species

Hophornbeam copperleaf (Acalypha ostryifolia Riddell) is an erect, herbaceous, dicot species in the Euphorbiaceae, or spurge, family that constitutes more than 200 genera and some 6,000 species (Mayfield and Webster 2013). Although the euphorbs have a cosmopolitan distribution, none are found in the Arctic (Mabberley 1997). Members of the Euphorbiaceae may be trees, shrubs, herbs (occasionally aquatic), or vines; sometimes succulent and cactus-like; and often have glands on vegetative plant parts (Mabberley 1997; Zomlefer 1994). Genera in the spurge family include Croton, Euphorbia, Ricinus, and Acalypha. Acalypha consists of 450 species that are native to both the Eastern and Western hemispheres (Zomlefer 1994). Acalypha was the name used by Hippocrates because the leaves resemble those of nettles, whereas ostryifolia alludes to the resemblance of leaves to plants in the genus Ostrya (hophornbeam trees; Burrows and Tyrl 2013; Haddock 2014; Hilty 2018). As plants mature in the fall, the leaves can turn reddish-brown, which may indicate why “copperleaf” is included in the species’ common name (Hilty 2018). Hophornbeam copperleaf is native to North America; it occurs in the United States ranging from Arizona east to Florida, north to Pennsylvania, and west to Nebraska (Anonymous 2019). It occurs in a variety of habitats including agronomic fields, cultivated areas, landscapes, roadsides, river and stream banks, thickets, pastures, and waste sites (Bryson and DeFelice 2010; Haddock 2014; Hilty 2018). This plant’s other common names include copperleaf, pineland three-seed mercury, Virginia copperleaf, hornbeam mercury, hornbeam three-seed mercury, mercury, and rough-pod copperleaf (Bryson and DeFelice 2010; Haddock 2014; Hilty 2018; Steckel 2006).

scholarly journals A North American ammonite fauna from the late Middle Turonian of Vaucluse and Gard, southern France: the Romaniceras mexicanum, Prionocyclus hyatti and Coilopoceras cf. springeri association

2016 ◽  
Vol 66 (4) ◽  
pp. 729-736 ◽  
Author(s):  
Francis Amédro ◽  
Francis Robaszynski ◽  
Bertrand Matrion ◽  
Christian Devalque
Keyword(s):  
United States ◽  
North America ◽  
Sea Level ◽  
Western Europe ◽  
Gulf Coast ◽  
First Record ◽  
The United States ◽  
Southern France ◽  
Gulf Coast Region ◽  
Coast Region

Abstract An unusual, exotic, ammonite fauna including Romaniceras mexicanum Jones, 1938, Prionocyclus hyatti (Stanton, 1894) and Coilopoceras cf. springeri Hyatt, 1903 is recorded from the late Middle Turonian of Vaucluse and Gard, southern France. It is the first record of this ammonite association outside the Gulf Coast region and the Western Interior of the United States of North America. Up to present, these species were considered as endemic to the Western Interior sea-way. The migration of numerous ammonites from North America to western Europe during the late Middle Turonian suggests it is linked to a transgressive event or to a short sea-level high.

Working With Interpreters to Support Students Who Are English Language Learners

2016 ◽  
Vol 1 (16) ◽  
pp. 15-27 ◽  
Author(s):  
Henriette W. Langdon ◽  
Terry Irvine Saenz
Keyword(s):  
United States ◽  
English Language Learners ◽  
Language Learners ◽  
English Language ◽  
First Language ◽  
The United States ◽  
The Other ◽  
Primary Language ◽  
Second Best ◽  
Support Students

The number of English Language Learners (ELL) is increasing in all regions of the United States. Although the majority (71%) speak Spanish as their first language, the other 29% may speak one of as many as 100 or more different languages. In spite of an increasing number of speech-language pathologists (SLPs) who can provide bilingual services, the likelihood of a match between a given student's primary language and an SLP's is rather minimal. The second best option is to work with a trained language interpreter in the student's language. However, very frequently, this interpreter may be bilingual but not trained to do the job.

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