Regional variation in the terminal Pleistocene and early Holocene radiocarbon record of eastern North America

2013 ◽  
Vol 79 (2) ◽  
pp. 175-188 ◽  
Author(s):  
D. Shane Miller ◽  
Joseph A.M. Gingerich
Keyword(s):  
North America ◽  
Regional Variation ◽  
Probability Distributions ◽  
Younger Dryas ◽  
Eastern North America ◽  
Northeastern United States ◽  
Radiocarbon Dates ◽  
Terminal Pleistocene ◽  
The Relationship ◽  
Data Result

AbstractIn this paper we use radiocarbon dates to evaluate the signature of the Younger Dryas Chronozone (YDC) in eastern North America. Using an approach that examines radiocarbon dates by region, we argue that the northeastern United States shows a better overall representation of radiocarbon dates when compared to the Mid-Atlantic and Southeast. These data result in a peak in summed probability distributions during the YDC, which is often interpreted as evidence of population growth. Further examination of these distributions, however, illustrates that differential standard deviations, varying sample size, and the effect of taphonomic and research biases likely overwhelm any demographic signatures in our study sample. Consequently, the frequency of radiocarbon dates by itself is insufficient for understanding the relationship between climate, culture and demography in eastern North America.

Distribution of the middorsal stripe dimorphism in the wood frog, Rana sylvatica, in eastern North America

1980 ◽  
Vol 58 (9) ◽  
pp. 1643-1651 ◽  
Author(s):  
Frederick W. Schueler ◽  
Francis R. Cook
Keyword(s):  
United States ◽  
North America ◽  
Rana Sylvatica ◽  
Wood Frog ◽  
Eastern North America ◽  
Hudson Bay ◽  
Northeastern United States ◽  
Southern Ontario ◽  
Maritime Canada ◽  
Eurasian Species

The frequency of the middorsally striped morph of Rana sylvatica in Ontario and Manitoba varies from absence in southern Ontario to 80% on the coast of Hudson Bay, with a general value of 20–30% in the boreal forest, a rise to 50% on the forest–grassland ecotone in southern Manitoba, and a decline westward to 20% on the edge of the prairies. This morph is rare in the northeastern United States and Maritime Canada. The suggested relationship between its frequency and the "grassiness" of the background on which predators view it is reexamined, and it is suggested that a linkage with earlier transformation as demonstrated in Eurasian species may explain certain anomalies.

Present and postglacial rates of uplift for glaciated northern and eastern North America derived from postglacial uplift curves

1970 ◽  
Vol 7 (2) ◽  
pp. 703-715 ◽  
Author(s):  
J. T. Andrews
Keyword(s):  
North America ◽  
Eastern North America ◽  
Hudson Bay ◽  
High Cell ◽  
Uplift Rate ◽  
Radiocarbon Dates ◽  
Marine Deposits ◽  
Maximum Value ◽  
Current Maximum ◽  
A Current

Average rates of postglacial uplift reach a maximum value of nearly 4 m 100 y−1 over southeastern Hudson Bay, and another high cell, with rates of about 2.5 m 100 y−1, lies between Bathurst Inlet and Southampton Island. Current rates of uplift are underestimated if exponential curves are fitted solely to dated raised marine deposits without considering the amount of future recovery. Rates of rebound are, instead, derived from A/t where A is uplift in the first 1000 y since deglaciation, and t is time since deglaciation. For the northwest margin of the former ice sheet coefficients of determination for rate of uplift, at specific times, as a function of distance are [Formula: see text]. Maps of rates of uplift for northern and eastern North America are presented for 8000 y B.P., 6000 y B.P. and the present day. They reveal the existence of three uplift centers and show that rates of uplift declined from a maximum of 10 to 12 m 100 y−1, immediately following deglaciation, to a current maximum of about 1.3 m 100 y−1. Agreement is satisfactory when calculated rates of uplift are compared with those derived from geological observations, radiocarbon dates, and from water-level records. A final map shows isochrones on the uplift rate of ~1 m 100 y−1. The rate dropped to this value about 10 000 y ago on the outer northwest and southeast coasts, whereas the value might not be reached for another 2000 y in southeastern Hudson Bay.

Detection of Adelges tsugae (Hemiptera: Adelgidae) wool using Velcro-covered balls

2021 ◽  
pp. 1-11
Author(s):  
Jeffrey G. Fidgen ◽  
Mark C. Whitmore ◽  
Chris J.K. MacQuarrie ◽  
Jean J. Turgeon
Keyword(s):  
Life Cycle ◽  
North America ◽  
Insect Pest ◽  
Adelges Tsugae ◽  
Eastern North America ◽  
Sample Sizes ◽  
Field Sampling ◽  
Individual Tree ◽  
Precision Level ◽  
The Relationship

Abstract Adelges tsugae Annand (Hemiptera: Adelgidae), a nonindigenous insect pest of hemlock (Tsuga spp.) (Pinaceae) in eastern North America, spends most of its life cycle within an ovisac, which resembles a woolly white mass on twigs. We evaluated the probability of detecting adelgid wool with Velcro®-covered balls when taking an increasing number of samples per tree (field sampling) and number of trees per simulated stand. We examined the relationship between the detection of adelgid wool using this technique and the incidence of A. tsugae-infested twigs by sampling lower-crown branch tips of the same trees. We found that the probability of detecting wool with ball sampling increased with number of ball samples per tree, with number of trees per simulated stand, and with increasing incidence of ovisacs in the lower crown. When sampling an individual tree, we found that 20 ball samples per tree achieved a targeted precision level of 0.75, but when sampling a stand, we found that 10 ball samples per tree took the least time for the range of simulated A. tsugae infestations we tested. These sample sizes are recommended for detection of A. tsugae infestations on an individual tree and in a hemlock stand.

scholarly journals Tree-Ring Records of Near-Younger Dryas Time in Central North America—Preliminary Results from the Lincoln Quarry Site, Central Illinois, Usa

Radiocarbon ◽  
2004 ◽  
Vol 46 (2) ◽  
pp. 933-941 ◽  
Author(s):  
Irina P Panyushkina ◽  
Steven W Leavitt ◽  
Alex Wiedenhoeft ◽  
Sarah Noggle ◽  
Brandon Curry ◽  
...  
Keyword(s):  
North America ◽  
Tree Ring ◽  
Environmental Changes ◽  
Ring Width ◽  
Younger Dryas ◽  
Late Glacial ◽  
Radiocarbon Dates ◽  
Initial Sampling ◽  
Central Illinois ◽  
A Site

The abrupt millennial-scale changes associated with the Younger Dryas (YD) event (“chronozone”) near the dawn of the Holocene are at least hemispheric, if not global, in extent. Evidence for the YD cold excursion is abundant in Europe but fairly meager in central North America. We are engaged in an investigation of high-resolution environmental changes in mid-North America over several millennia (about 10,000 to 14,000 BP) during the Late Glacial–Early Holocene transition, including the YD interval. Several sites containing logs or stumps have been identified and we are in the process of initial sampling or re-sampling them for this project. Here, we report on a site in central Illinois containing a deposit of logs initially thought to be of YD age preserved in alluvial sands. The assemblage of wood represents hardwood (angiosperm) trees, and the ring-width characteristics are favorable to developing formal tree-ring chronologies. However, 4 new radiocarbon dates indicate deposition of wood may have taken place over at least 8000 14C yr (6000–14,000 BP). This complicates the effort to develop a single floating chronology of several hundred years at this site, but it may provide wood from a restricted region over a long period of time from which to develop a sequence of floating chronologies, the timing of deposition and preservation of which could be related to paleoclimatic events and conditions.

scholarly journals Rain, Riches, and Empire: The Relationship between Nations Ruling Distant Lands, Nations of Great Wealth, and Regions of Regular Moderate Atmospheric Precipitation

2017 ◽  
Vol 9 (3) ◽  
pp. 455-469 ◽  
Author(s):  
L. Bruce Railsback
Keyword(s):  
North America ◽  
Small Proportion ◽  
Average Rate ◽  
Atmospheric Precipitation ◽  
Eastern North America ◽  
Human History ◽  
Per Capita Gdp ◽  
Per Capita ◽  
Human Construction ◽  
The Relationship

Abstract Two of the great questions of human history and economics are why some nations held far-flung empires and why some presently enjoy great wealth. One factor that should be included in the inevitably multifactorial answer to these questions is regular moderate precipitation (precipitation with an average rate between 30 and 120 mm for each month). Only a small proportion of Earth’s surface has regular moderate precipitation, and most of that area is in Europe and eastern North America. Strikingly, of the 13 nations that held geographically discontinuous multicontinental transoceanic empires, 12 overlap with regions of regular moderate precipitation. Similarly, of the 20 nations with the greatest per capita GDP in 2015, 16 coincide with regions of regular moderate precipitation. These relationships are presumably rooted in the greater success, or lesser inhibition, of human construction of infrastructure, husbandry of livestock, and cultivation of crops, some combination of which likely allowed industrialization, projection of geopolitical power, and accumulation of wealth. One instructive example is that of China, which has a climate superficially like that of Europe and eastern North America but no regions of regular moderate rainfall, and which neither developed an overseas empire nor is among the world’s nations with greatest per capita GDP. Furthermore, concentration of nations holding empires and wealth in the Northern Hemisphere and their absence from the south can be linked to the coincidence that the Southern Hemisphere’s latitudinal zone of regular moderate rainfall is over the Southern Ocean, where there is little land on which human societies could have enjoyed the benefits of that supportive climate.

Taxonomy of the Carex straminea complex (Cyperaceae)

1997 ◽  
Vol 75 (12) ◽  
pp. 2177-2195 ◽  
Author(s):  
P. E. Rothrock ◽  
A. A. Reznicek ◽  
L. R. Ganion
Keyword(s):  
Numerical Analysis ◽  
North America ◽  
Key Words ◽  
Endemic Species ◽  
Atlantic Coast ◽  
Interspecific Variation ◽  
Eastern North America ◽  
Upper Midwest ◽  
The Relationship ◽  
Sem Investigation

The Carex straminea complex (section Ovales) consists of five species limited to hydric communities of eastern North America. Based upon gross morphology and perigynium structure, these species are closely aligned with the Carex albolutescens complex but not the western species Carex feta. An SEM investigation of the micromorphology of achene and style epidermis from 15 species of Carex section Ovales demonstrated much interspecific variation. As a result, these data could not confirm the relationship between the C. straminea complex and the C. albolutescens complex but did support the delimitation of section Ovales. Numerical analysis showed that characters of the inflorescence and perigynium are satisfactory for separating C. straminea from Carex hormathodes, a species limited to the Atlantic coast. Likewise, characters of inflorescence, pistillate scale, and perigynium could clearly separate the geographically widespread Carex alata from the Florida endemic species Carex vexans. A fifth and relatively distinctive species, Carex suberecta, was found to have a narrow ecological preference for fens and a distribution limited to the upper Midwest, with outlying populations in western Virginia. Putative natural hybrids are documented between Carex scoparia and Carex longii and some species in the C. straminea complex. Key words: Carex, Cyperaceae, section Ovales, taxonomy, SEM, biogeography, hybrid.

Lithocolletis blancardella Fabricius (Lepidoptera: Gracilariidae) on Apple in Eastern North America with Notes on Other Species Occurring on Rosaceae

1964 ◽  
Vol 96 (11) ◽  
pp. 1442-1449 ◽  
Author(s):  
H. T. Stultz
Keyword(s):  
United States ◽  
North America ◽  
Leaf Miner ◽  
Eastern North America ◽  
Similar Species ◽  
Black Cherry ◽  
Northeastern United States ◽  
Maritime Provinces ◽  
Eastern Canada ◽  
Large Numbers

AbstractA spotted tentiform leaf miner, often present during recent years in large numbers in apple orchards in the Maritime Provinces of Canada, is identified as Lithocolletis blancardella Fabr., a species common on apples in Europe. Recent collecting indicates that the species occurs widely in Eastern Canada and the northeastern United States. Diagnostic characters, especially those of the male genitalia, are compared with those of specimens identified as L. crataegella Clem. and L. propinquinella Braun, two similar species which commonly occur on apple and black cherry respectively.

Some Amerasian Pottery Traits in North Asian Prehistory

1953 ◽  
Vol 19 (1) ◽  
pp. 25-39 ◽  
Author(s):  
Paul Tolstoy
Keyword(s):  
United States ◽  
North America ◽  
New World ◽  
The United States ◽  
Eastern North America ◽  
Eastern Siberia ◽  
Radiocarbon Dates ◽  
Old World ◽  
The Subject

Asiatic origins have, at one time or another, been suggested or at least considered for a number of traits connected with the manufacture and decoration of the earlier New World pottery. The well-known paper by McKern (1937) is among the most explicit statements on the subject. Griffin (1946; Sears and Griffin 1950a) has held similar views for some time. Like McKern, he has primarily in mind traits of the Woodland pattern of eastern North America, although he also mentions some non-Woodland traits among those which have counterparts in the Old World (1946, p. 45).Since McKern's paper, the distribution in time of the traits involved has become a lot better established. With the help of the still suspiciously regarded radiocarbon dates, our perspective on ceramic history in the United States has been extended over a span which appears to be that of some four millennia. Among the more significant additions to the Asiatic half of the distributional picture first place must be given to recent Soviet work in eastern Siberia.

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