Spiroplasma montanense sp. nov., from Hybomitra Horseflies at Northern Latitudes in North America

AbstractMany temperate plant genera, likeSambucus, have species with range disjunctions among North America, Europe and/or Asia. Cold stratification (sometimes in combination with warm stratification) is the primary mechanism to break seed dormancy in these species. For some of these genera showing Northern Hemispheric disjunctions, members also occur in subtropical or tropical regions, mostly confined to higher elevations where climate and vegetation differ from those in northern latitudes. We made two hypotheses concerning germination for the subtropical TaiwaneseSambucus chinensis: (1) seeds from populations exposed to warm temperatures would require warm stratification, and (2) seeds from populations exposed to cold temperatures need cold stratification. We investigated the germination (including embryo growth) of non-stratified seeds over a range of temperatures and tested the effects of cold stratification and of gibberellins GA3and GA4on germination. The amount and timing of germination among populations varied substantially in response to temperature treatments. Seeds from all populations of this species required warm temperatures for dormancy break and germination, regardless of environmental conditions. As such, the majority of seeds had non-deep simple morphophysiological dormancy, which, until now, has not been reported in any members ofSambucus. The seed characteristics of the subtropicalS. chinensisare different from those of temperate members of the genus in which cold stratification is the predominate treatment to overcome dormancy.

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Bears

10.5744/florida/9781683401384.001.0001 ◽

2020 ◽

Keyword(s):

Native American ◽

North America ◽

Special Treatment ◽

Ample Evidence ◽

Native Peoples ◽

Atlantic Trade ◽

Economic Significance ◽

Northern Latitudes ◽

Comparative Ethnography ◽

Native North America

Thanks to Irving Hallowell’s classic 1926 comparative ethnography on the special mythic status of bears in Subarctic cultures, anthropologists are generally aware that peoples throughout the northern hemisphere have treated bears as far more than a subsistence resource, something more akin to another kind of human or, to use Hallowell’s famous phrase, “other-than-human persons.” While Hallowell provided ample evidence of bear ceremonialism in northern latitudes, he found little evidence for the special treatment of bears elsewhere in Native North America. Archaeological and historical research over the last nine decades, however, has produced vast unsynthesized information about the roles of bears in Native American beliefs, rituals, and subsistence. This book is the first collective effort since Hallowell’s formative publication to consider how Native peoples viewed, treated, and used black bears (Ursus americanus) through time across Eastern North America. Contributors draw on zooarchaeological, ethnohistorical, ethnographic, and other evidence of bear hunting, consumption, and use, while contemplating the range of relationships that existed between bears and humans. They have reviewed thousands of pages of ethnohistorical and ethnographic documents and summarized and interpreted data on bear remains from nearly 300 archaeological sites from Quebec to the Gulf of Mexico. Native peoples perceived and related to bears in remarkably diverse ways. Our authors explore the religious and economic significance of bears and bear products (meat, fat, oil, pelts, etc.), bear imagery in Native art and artifacts, and bears in Native worldviews, kinship systems, and cosmologies, along with their role as exported commodities in trans-Atlantic trade.

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Moose genomes reveal past glacial demography and the origin of modern lineages

BMC Genomics ◽

10.1186/s12864-020-07208-3 ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

Nicolas Dussex ◽

Federica Alberti ◽

Matti T. Heino ◽

Remi-Andre Olsen ◽

Tom van der Valk ◽

...

Keyword(s):

North America ◽

De Novo ◽

Demographic History ◽

Glacial Refugia ◽

Population Declines ◽

Glacial Cycles ◽

Climate Fluctuations ◽

Northern Latitudes ◽

Genomic Studies ◽

History Of

Abstract Background Numerous megafauna species from northern latitudes went extinct during the Pleistocene/Holocene transition as a result of climate-induced habitat changes. However, several ungulate species managed to successfully track their habitats during this period to eventually flourish and recolonise the holarctic regions. So far, the genomic impacts of these climate fluctuations on ungulates from high latitudes have been little explored. Here, we assemble a de-novo genome for the European moose (Alces alces) and analyse it together with re-sequenced nuclear genomes and ancient and modern mitogenomes from across the moose range in Eurasia and North America. Results We found that moose demographic history was greatly influenced by glacial cycles, with demographic responses to the Pleistocene/Holocene transition similar to other temperate ungulates. Our results further support that modern moose lineages trace their origin back to populations that inhabited distinct glacial refugia during the Last Glacial Maximum (LGM). Finally, we found that present day moose in Europe and North America show low to moderate inbreeding levels resulting from post-glacial bottlenecks and founder effects, but no evidence for recent inbreeding resulting from human-induced population declines. Conclusions Taken together, our results highlight the dynamic recent evolutionary history of the moose and provide an important resource for further genomic studies.

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Top-down estimates of black carbon emissions at high latitudes using an atmospheric transport model and a Bayesian inversion framework

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-15307-2018 ◽

2018 ◽

Vol 18 (20) ◽

pp. 15307-15327 ◽

Cited By ~ 2

Author(s):

Nikolaos Evangeliou ◽

Rona L. Thompson ◽

Sabine Eckhardt ◽

Andreas Stohl

Keyword(s):

North America ◽

Biomass Burning ◽

Oil And Gas ◽

Transport Model ◽

Atmospheric Transport ◽

A Priori ◽

Gas Production ◽

Anthropogenic Sources ◽

A Posteriori ◽

Northern Latitudes

Abstract. This paper presents the results of BC inversions at high northern latitudes (> 50° N) for the 2013–2015 period. A sensitivity analysis was performed to select the best representative species for BC and the best a priori emission dataset. The same model ensemble was used to assess the uncertainty of the a posteriori emissions of BC due to scavenging and removal and due to the use of different a priori emission inventory. A posteriori concentrations of BC simulated over Arctic regions were compared with independent observations from flight and ship campaigns showing, in all cases, smaller bias, which in turn witnesses the success of the inversion. The annual a posteriori emissions of BC at latitudes above 50° N were estimated as 560±171 kt yr−1, significantly smaller than in ECLIPSEv5 (745 kt yr−1), which was used and the a priori information in the inversions of BC. The average relative uncertainty of the inversions was estimated to be 30 %.A posteriori emissions of BC in North America are driven by anthropogenic sources, while biomass burning appeared to be less significant as it is also confirmed by satellite products. In northern Europe, a posteriori emissions were estimated to be half compared to the a priori ones, with the highest releases to be in megacities and due to biomass burning in eastern Europe. The largest emissions of BC in Siberia were calculated along the transect between Yekaterinsburg and Chelyabinsk. The optimised emissions of BC were high close to the gas flaring regions in Russia and in western Canada (Alberta), where numerous power and oil and gas production industries operate. Flaring emissions in Nenets–Komi oblast (Russia) were estimated to be much lower than in the a priori emissions, while in Khanty-Mansiysk (Russia) they remained the same after the inversions of BC. Increased emissions at the borders between Russia and Mongolia are probably due to biomass burning in villages along the Trans-Siberian Railway. The maximum BC emissions in high northern latitudes (> 50° N) were calculated for summer months due to biomass burning and they are controlled by seasonal variations in Europe and Asia, while North America showed a much smaller variability.

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Methane fluxes in the high northern latitudes for 2005–2013 estimated using a Bayesian atmospheric inversion

10.5194/acp-2016-660 ◽

2016 ◽

Author(s):

Rona L. Thompson ◽

Motoki Sasakawa ◽

Toshinobu Machida ◽

Tuula Aalto ◽

Doug Worthy ◽

...

Keyword(s):

North America ◽

Soil Temperature ◽

Land Surface ◽

Dispersion Model ◽

Land Surface Model ◽

Particle Dispersion ◽

Anthropogenic Sources ◽

Surface Model ◽

Northern Latitudes ◽

North Eurasia

Abstract. We present methane (CH4) flux estimates for 2005 to 2013 from a Bayesian inversion focusing on the high northern latitudes (north of 50° N). Our inversion is based on atmospheric transport modelled by the Lagrangian particle dispersion model, FLEXPART, and CH4 observations from 17 in-situ and 5 discrete flask-sampling sites distributed over northern North America and Eurasia. CH4 fluxes are determined at monthly temporal resolution and on a variable grid with maximum resolution of 1° × 1°. Our inversion finds a CH4 source from the high northern latitudes of 82 to 84 Tg y−1, constituting ~15 % of the global total, compared to 64 to 68 Tg y−1 (~12 %) in the prior estimates. For northern North America, we estimate a mean source of 16.6 to 17.9 Tg y−1, which is dominated by fluxes in the Hudson Bay Lowlands (HBL) and western Canada, specifically, the province of Alberta. Our estimate for the HBL, of 2.7 to 3.4 Tg y−1, is close to the prior estimate (which includes wetland fluxes from the land surface model, LPX-Bern) and to other independent inversion estimates. However, our estimate for Alberta, of 5.0 to 5.8 Tg y−1 is significantly higher than the prior (which also includes anthropogenic sources from the EDGAR-4.2FT2010 inventory). Since the fluxes from this region persist throughout the winter, this may signify that the anthropogenic emissions are underestimated. For North Eurasia, we find a mean source of 52.2 to 55.5 Tg y−1, with a strong contribution from fluxes in the Western Siberian Lowlands (WSL) for which we estimate a source of 19.3 to 19.9 Tg y−1. Over the 9-year inversion period, we find significant year-to-year variations in the fluxes, which in North America and, specifically, in the HBL appear to be driven at least in part by soil temperature, while in the WSL, the variability is more dependent on soil moisture. Moreover, we find significant positive trends in the CH4 fluxes in North America of 0.38 to 0.57 Tg y−1 per year, and North Eurasia of 0.76 to 1.09 Tg y−1 per year. In North America, this could be due to an increase in soil temperature, while in North Eurasia, specifically, Russia, the trend is likely due, at least in part, to an increase in anthropogenic sources.

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Common Ragweed Ecotypes

Weed Science ◽

10.1017/s0043174500048281 ◽

1971 ◽

Vol 19 (1) ◽

pp. 64-66 ◽

Cited By ~ 36

Author(s):

C. T. Dickerson ◽

R. D. Sweet

Keyword(s):

New York ◽

North America ◽

Growth And Development ◽

Dry Weight ◽

Ambrosia Artemisiifolia ◽

Day Length ◽

Common Ragweed ◽

Northern Latitudes ◽

The Difference ◽

Viable Seeds

Seed of common ragweed (Ambrosia artemisiifolia L.) ecotypes were collected from 12 locations in North America and were planted at Ithaca, New York. Plants from seed collected in the northern latitudes flowered earlier and produced less vegetative growth. The difference in growth and development of the ecotypes was caused by the day length or latitude where they had originated. Seedlings emerging in early July produced approximately one-third as much fresh or dry weight and about one-third as many viable seeds as those emerging in the middle of May. The latter produced more than 32,000 seed per plant.

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Changes in statistical distributions of sub-daily surface temperatures and wind speed

Earth System Dynamics ◽

10.5194/esd-10-765-2019 ◽

2019 ◽

Vol 10 (4) ◽

pp. 765-788 ◽

Cited By ~ 1

Author(s):

Robert J. H. Dunn ◽

Kate M. Willett ◽

David E. Parker

Keyword(s):

North America ◽

Eastern China ◽

Dew Point ◽

Statistical Distributions ◽

Point Temperature ◽

Dew Point Temperature ◽

Wind Speeds ◽

Northern Latitudes ◽

Standard Deviations ◽

Autumn And Winter

Abstract. With the ongoing warming of the globe, it is important to quantify changes in the recent behaviour of extreme events given their impacts on human health, infrastructure and the natural environment. We use the sub-daily, multivariate, station-based HadISD dataset to study the changes in the statistical distributions of temperature, dew point temperature and wind speeds. Firstly, we use zonally averaged quantities to show that the lowest temperatures during both day and night are changing more rapidly than the highest, with the effect more pronounced in the northern high latitudes. Along with increases in the zonally averaged mean temperature, the standard deviation has decreased and the skew increased (increasing positive tail, decreasing negative tail) over the last 45 years, again with a stronger, more robust signal at higher latitudes. Changes in the distribution of dew point temperature are similar to those of temperature. However, changes in the distribution of wind speeds indicate a more rapid change at higher speeds than at lower. Secondly, to assess in more detail the spatial distribution of changes as well as changes across seasons and hours of the day we study each station individually. For stations which show clear indications of change in the statistical moments, the higher the statistical moment, generally the more spatially heterogenous the patterns of change. The standard deviations of temperatures are increasing in a band stretching from Europe through China but are decreasing across North America and in the high northern latitudes, indicating broadening and narrowing of the distributions, respectively. Large seasonal differences are found in the change of standard deviations of temperatures over North America and eastern China. Temperatures in eastern Asia also have increasing skew in the winter in contrast to the remainder of the year. The dew point temperatures show smaller variation in all of the moments but similar patterns to the temperatures. For wind speeds, apart from the USA, standard deviations are decreasing across the world, indicating a decrease in variability. Finally, we use quantile regression to show changes in the percentiles of distributions over time. These show an increase in high quantiles of temperature in eastern Europe during the summer and also in northern Europe for low quantiles in the winter, also indicating broadening and narrowing of the distributions, respectively. In North America, the largest changes are at the lower quantiles in northern latitudes for autumn and winter. Quantiles of dew point temperature are changing most in the autumn and winter, especially in the northern parts of Europe.

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The Influence of Stratospheric Vortex Displacements and Splits on Surface Climate

Journal of Climate ◽

10.1175/jcli-d-12-00030.1 ◽

2013 ◽

Vol 26 (8) ◽

pp. 2668-2682 ◽

Cited By ~ 138

Author(s):

Daniel M. Mitchell ◽

Lesley J. Gray ◽

James Anstey ◽

Mark P. Baldwin ◽

Andrew J. Charlton-Perez

Keyword(s):

North America ◽

Time Scales ◽

Polar Vortex ◽

Reanalysis Data ◽

The Arctic ◽

Positive Temperature ◽

Cold Air ◽

Weather Patterns ◽

Northern Latitudes ◽

Stratospheric Variability

Abstract A strong link exists between stratospheric variability and anomalous weather patterns at the earth’s surface. Specifically, during extreme variability of the Arctic polar vortex termed a “weak vortex event,” anomalies can descend from the upper stratosphere to the surface on time scales of weeks. Subsequently the outbreak of cold-air events have been noted in high northern latitudes, as well as a quadrupole pattern in surface temperature over the Atlantic and western European sectors, but it is currently not understood why certain events descend to the surface while others do not. This study compares a new classification technique of weak vortex events, based on the distribution of potential vorticity, with that of an existing technique and demonstrates that the subdivision of such events into vortex displacements and vortex splits has important implications for tropospheric weather patterns on weekly to monthly time scales. Using reanalysis data it is found that vortex splitting events are correlated with surface weather and lead to positive temperature anomalies over eastern North America of more than 1.5 K, and negative anomalies over Eurasia of up to −3 K. Associated with this is an increase in high-latitude blocking in both the Atlantic and Pacific sectors and a decrease in European blocking. The corresponding signals are weaker during displacement events, although ultimately they are shown to be related to cold-air outbreaks over North America. Because of the importance of stratosphere–troposphere coupling for seasonal climate predictability, identifying the type of stratospheric variability in order to capture the correct surface response will be necessary.

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Changes in statistical distributions of sub-daily surface temperatures and wind speed

10.5194/esd-2019-39 ◽

2019 ◽

Author(s):

Robert J. H. Dunn ◽

Kate M. Willett ◽

David E. Parker

Keyword(s):

Standard Deviation ◽

North America ◽

Eastern China ◽

Rapid Change ◽

Statistical Distributions ◽

Wind Speeds ◽

Dewpoint Temperature ◽

Northern Latitudes ◽

Standard Deviations ◽

Autumn And Winter

Abstract. With the ongoing warming of the globe, it is important to quantify changes in the recent behaviour of extreme events given their impacts on human health, infrastructure and the natural environment. We use the sub-daily, multi-variate, station-based HadISD dataset to study the changes in the statistical distributions of temperature, dewpoint temperature and wind speeds. Firstly, we use zonally averaged quantities to show that the lowest temperatures during both day and night are changing more rapidly than the highest, with the effect more pronounced in the northern high latitudes. Along with an increases in the zonally-averaged mean temperature, the standard deviation has decreased and the skew increased (increasing positive tail/decreasing negative tail) over the last 45 years, again with a stronger, more robust signal at higher latitudes. Changes in the distribution of dewpoint temperature are similar to those of temperature. However, changes in the distribution of wind speeds indicate a more rapid change at higher speeds than at lower. Secondly, to assess in more detail the spatial distribution of changes as well as across seasons and hours of the day we study each station individually. For stations which show clear indications of change in the statistical moments, the higher the statistical moment, generally the more spatially heterogenous the patterns of change. The standard deviation of temperatures are increasing in a band stretching from Europe through to China, but are decreasing across North America and in the high northern latitudes, indicating broadening and narrowing of the distributions respectively. Large seasonal differences are found in the change of standard deviations of temperatures over North America and eastern China. Temperatures in Eastern Asia also have increasing skew in the winter in contrast to the remainder of the year. The dewpoint temperatures show smaller variation in all of the moments, but similar patterns to the temperatures. For wind speeds, apart from the USA, standard deviations are decreasing across the world, indicating a decrease in variability. Finally, we use quantile regression to show changes in the percentiles of distributions over time. These show an increase of high quantiles of temperature in eastern Europe during the summer, and also in northern Europe for low quantiles in the winter, also indicating broadening and narrowing of the distributions respectively. In North America, the largest changes are at the lower quantiles in northern latitudes for autumn and winter. Quantiles of dewpoint temperature are changing most in the autumn and winter, especially in the northern parts of Europe.

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Borrelia kurtenbachii sp. nov., a widely distributed member of the Borrelia burgdorferi sensu lato species complex in North America

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY ◽

10.1099/ijs.0.054593-0 ◽

2014 ◽

Vol 64 (Pt_1) ◽

pp. 128-130 ◽

Cited By ~ 35

Author(s):

Gabriele Margos ◽

Joseph Piesman ◽

Robert S. Lane ◽

Nicholas H. Ogden ◽

Andreas Sing ◽

...

Keyword(s):

North America ◽

Borrelia Burgdorferi ◽

Type Species ◽

Species Complex ◽

Sensu Stricto ◽

Borrelia Burgdorferi Sensu Lato ◽

Content Type ◽

Link Type ◽

The North ◽

Northern Latitudes

Lyme borreliosis group spirochaetes are parasitic bacteria transmitted by vector ticks of the genus Ixodes and distributed mainly between 40° and 60° northern latitudes. Since Borrelia burgdorferi sensu stricto (hereinafter, B. burgdorferi ) was described in the north-eastern USA during the early 1980s, an increasing diversity has been noted within the species complex. Here, we describe a novel genomic species, Borrelia kurtenbachii sp. nov. (type strain 25015T = ATCC BAA-2495T = DSM 26572T), that is prevalent in transmission cycles among vector ticks and reservoir hosts in North America. Confirmation of the presence of this species in Europe awaits further investigation.

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