scholarly journals A clinal polymorphism in the insulin signaling transcription factorfoxocontributes to life-history adaptation inDrosophila

2018 ◽  
Author(s):  
Esra Durmaz ◽  
Subhash Rajpurohit ◽  
Nicolas Betancourt ◽  
Daniel K. Fabian ◽  
Martin Kapun ◽  
...  
Keyword(s):  
Life History ◽  
High Latitude ◽  
Growth Factor Signaling ◽  
Starvation Resistance ◽  
The North ◽  
Natural Variants ◽  
Two Temperatures ◽  
Genetics Of Adaptation ◽  
Outbred Populations ◽  
Sugar Source

AbstractA fundamental aim of adaptation genomics is to identify polymorphisms that underpin variation in fitness traits. InD. melanogasterlatitudinal life-history clines exist on multiple continents and make an excellent system for dissecting the genetics of adaptation. We have previously identified numerous clinal SNPs in insulin/insulin-like growth factor signaling (IIS), a pathway known from mutant studies to affect life history. However, the effects of natural variants in this pathway remain poorly understood. Here we investigate how two clinal alternative alleles atfoxo, a transcriptional effector of IIS, affect fitness components (viability, size, starvation resistance, fat content). We assessed this polymorphism from the North American cline by reconstituting outbred populations, fixed for either the low- or high-latitude allele, from inbred DGRP lines. Since diet and temperature modulate IIS, we phenotyped alleles across two temperatures (18°C, 25°C) and two diets differing in sugar source and content. Consistent with clinal expectations, the high-latitude allele conferred larger body size and reduced wing loading. Alleles also differed in starvation resistance and expression ofInR, a transcriptional target of FOXO. Allelic reaction norms were mostly parallel, with few GxE interactions. Together, our results suggest that variation in IIS makes a major contribution to clinal life-history adaptation.

scholarly journals North Atlantic warming over six decades drives decreases in krill abundance with no associated range shift

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Martin Edwards ◽  
Pierre Hélaouët ◽  
Eric Goberville ◽  
Alistair Lindley ◽  
Geraint A. Tarling ◽  
...  
Keyword(s):  
North Atlantic ◽  
Range Shift ◽  
The Core ◽  
Krill Abundance ◽  
The North ◽  
Living Space ◽  
Warming Climate ◽  
Two Temperatures ◽  
The North Atlantic

AbstractIn the North Atlantic, euphausiids (krill) form a major link between primary production and predators including commercially exploited fish. This basin is warming very rapidly, with species expected to shift northwards following their thermal tolerances. Here we show, however, that there has been a 50% decline in surface krill abundance over the last 60 years that occurred in situ, with no associated range shift. While we relate these changes to the warming climate, our study is the first to document an in situ squeeze on living space within this system. The warmer isotherms are shifting measurably northwards but cooler isotherms have remained relatively static, stalled by the subpolar fronts in the NW Atlantic. Consequently the two temperatures defining the core of krill distribution (7–13 °C) were 8° of latitude apart 60 years ago but are presently only 4° apart. Over the 60 year period the core latitudinal distribution of euphausiids has remained relatively stable so a ‘habitat squeeze’, with loss of 4° of latitude in living space, could explain the decline in krill. This highlights that, as the temperature warms, not all species can track isotherms and shift northward at the same rate with both losers and winners emerging under the ‘Atlantification’ of the sub-Arctic.

Response time of the high-latitude dayside ionosphere to sudden changes in the north-south component of the IMF

1988 ◽  
Vol 36 (12) ◽  
pp. 1415-1428 ◽  
Author(s):  
H. Todd ◽  
S.W.H. Cowley ◽  
M. Lockwood ◽  
D.M. Willis ◽  
H. Lühr
Keyword(s):  
Response Time ◽  
High Latitude ◽  
The North ◽  
The Imf

The Life History of Babesia bigemina in the North American Fever Tick

Science ◽  
1931 ◽  
Vol 73 (1901) ◽  
pp. 620-621
Author(s):  
Emery Westervelt Dennis
Keyword(s):  
Life History ◽  
North American ◽  
Babesia Bigemina ◽  
The North ◽  
History Of

scholarly journals Larval density, temperature and biological aspects of Chrysomya megacephala (Diptera: Calliphoridae)

2006 ◽  
Vol 58 (4) ◽  
pp. 562-566 ◽  
Author(s):  
C. Reigada ◽  
W.A.C. Godoy
Keyword(s):  
Population Dynamics ◽  
Life History ◽  
Body Size ◽  
Larval Density ◽  
Chrysomya Megacephala ◽  
Life History Characteristics ◽  
Two Temperatures ◽  
Biological Aspects ◽  
Experimental Populations ◽  
Simultaneous Influence

The effect of larval density on the survival, fecundity and body size at two temperatures in experimental populations of C. megacephala was studied. No effect from simultaneous influence of density and temperature on life history characteristics of C. megacephala was found. Significant effects of density and temperature on survival, fecundity and body size were observed. The importance of these results for the population dynamics of C. megacephala is discussed.

Efficient carbon drawdown allows for a high future carbon uptake in the North Atlantic

2021 ◽  
Author(s):  
Nadine Goris ◽  
Jerry Tjiputra ◽  
Are Ohlsen ◽  
Jörg Schwinger ◽  
Siv Lauvset ◽  
...  
Keyword(s):  
North Atlantic ◽  
High Latitude ◽  
Deep Convection ◽  
Deep Ocean ◽  
Nutrient Supply ◽  
Global Ocean ◽  
Carbon Uptake ◽  
Model Ensemble ◽  
The North ◽  
The North Atlantic

<p>As one of the major carbon sinks in the global ocean, the North Atlantic is a key player in mediating and ameliorating the ongoing global warming. Projections of the North Atlantic carbon sink in a high-CO<sub>2</sub> future vary greatly among models, with some showing that a slowdown in carbon uptake has already begun and others predicting that this slowdown will not occur until nearly 2100.</p><p>Discrepancies among models largely originate because of differences in the efficiency of the high-latitude transport of carbon from the surface to the deep ocean. This transport occurs through biological production, deep convection and subsequent transport via the deep western boundary current. For an ensemble of 11 CMIP5-models, we studied the efficiency of this transport and identified two indicators of contemporary model behavior that are highly correlated with a model´s projected future carbon-uptake. The first indicator is the high latitude summer pCO<sub>2</sub><sup>sea</sup>-anomaly of a model, which is tightly linked to winter mixing and nutrient supply, but also to deep convection. The second indicator is the fraction of the anthropogenic carbon-inventory stored below 1000-m depth, indicating how efficient carbon is transported into the deep ocean. By comparing to the observational database, these indicators allow us to better constrain the model ensemble, and demonstrate that the models with more efficient surface to deep transport are best aligned with current observations. These models also show the largest future North Atlantic carbon uptake, which we then conclude is the more plausible future evolution. We further study if the high correlations between our contemporary indicators and a model´s future North Atlantic carbon uptake is also upheld for the next model generation, CMIP6. We hypothesize that this is the case and that our indicators can not only help us to constrain the CMIP6 model ensemble but also inform us about progress made between CMIP5 and CMIP6 in terms of North Atlantic carbon uptake, winter mixing, nutrient supply, deep convection and transport of carbon into the deep ocean.</p>

Machines and Media

2017 ◽  
Keyword(s):  
World War Ii ◽  
High Latitude ◽  
World War ◽  
Physics Laboratory ◽  
The North ◽  
The People ◽  
International Collaborations ◽  
Local Problems ◽  
Multiple Meanings

This chapter sets the stage for DRTE’s linking of nature and technology by examining anxieties about ionosondes — the chief instruments of ionospheric research. The ionosondes that emerged from World War II could not be trusted to capture rapidly-changing high-latitude phenomena. The chapter focuses on the efforts of Frank Davies and the Radio Physics Laboratory to create a coherent group of instruments, collectively responsible for mapping northern sectors of the global ionosphere. In doing so, it illustrates how efforts to standardize ionospheric equipment, as well as the multiple meanings of that standardization, opened up important possibilities for variation and difference in international collaborations. For Frank Davies and his group, the machines and the records they produced became a way of solving all-too-local problems with the North as a place of experiment and with the people occupying it.

The Life History and Dispersal of the Bruce Spanworm, Operophtera bruceata (Hulst), (Lepidoptera: Geometridae)

1962 ◽  
Vol 94 (10) ◽  
pp. 1103-1107 ◽  
Author(s):  
C. E. Brown
Keyword(s):  
United States ◽  
Life History ◽  
The United States ◽  
American Continent ◽  
Forest Insect ◽  
North American Continent ◽  
The Third ◽  
The North ◽  
Insect Survey ◽  
Bruce Spanworm

The Bruce spanworrn, Operophtera bruceata (Hulst), is most common in the mid latitudes of the North American Continent; in Canada it occurs from Newfoundland to the interior of British Columbia (Prentice, In Press) and has been reported from Vermont and Wisconsin in the United States (Craighead, 1950.) Three outbreaks of this insect have been recorded in Alberta. The first occurred in 1903 (de Gryse, 1925) and was apparently of short duration. The second reported by Wolley Dod (1913) occurred in 1913 and denuded hundreds of acres of aspen poplar. Heavy defoliation in the third outbreak became evident in 1957 (Brown, 1957) but an examination of Forest Insect Survey records revealed that population buildup began about 1951. The outbreak continued to expand until 1958 and began to decline in 1959; by 1961 populations were again low except for one or two isolated areas where moderate to low populations persisted. At the peak of the outbreak in 1958 approximately 50,000 square miies were moderately or heavily infested and many more lightly infested.

Functional traits and life history diversity of the North Africa endemic Ebenus pinnata Aiton

Flora ◽  
2010 ◽  
Vol 205 (10) ◽  
pp. 666-673 ◽  
Author(s):  
A.K. Hegazy ◽  
H.F. Kabiel ◽  
L. Boulos ◽  
O.S. Sharashy
Keyword(s):  
Life History ◽  
Functional Traits ◽  
North Africa ◽  
The North
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