scholarly journals On temperance and risk spreading

2019 ◽  
Vol 88 (4) ◽  
pp. 527-539
Author(s):  
Christophe Courbage ◽  
Béatrice Rey
Keyword(s):  
Risk Spreading

Elevated nest predation risk promotes offspring size variation in birds with prolonged parental care.

2019 ◽  
Author(s):  
Gretchen F. Wagner ◽  
Emeline Mourocq ◽  
Michael Griesser
Keyword(s):  
Predation Risk ◽  
Reproductive Cycle ◽  
Perceived Risk ◽  
Nest Predation ◽  
Bird Species ◽  
Size Variation ◽  
Egg Laying ◽  
Offspring Size ◽  
Natural Predation ◽  
Risk Spreading

Predation of offspring is the main cause of reproductive failure in many species, and the mere fear of offspring predation shapes reproductive strategies. Yet, natural predation risk is ubiquitously variable and can be unpredictable. Consequently, the perceived prospect of predation early in a reproductive cycle may not reflect the actual risk to ensuing offspring. An increased variance in investment across offspring has been linked to breeding in unpredictable environments in several taxa, but has so far been overlooked as a maternal response to temporal variation in predation risk. Here, we experimentally increased the perceived risk of nest predation prior to egg-laying in seven bird species. Species with prolonged parent-offspring associations increased their intra-brood variation in egg, and subsequently offspring, size. High risk to offspring early in a reproductive cycle can favour a risk-spreading strategy particularly in species with the greatest opportunity to even out offspring quality after fledging.

Egg retention as risk-spreading in Trichogramma

2007 ◽  
Vol 148 (3) ◽  
pp. 340
Author(s):  
Sergey Reznik ◽  
Nina Vaghina ◽  
Natalia Voinovich ◽  
Svetlana Karpova
Keyword(s):  
Egg Retention ◽  
Risk Spreading

Is Risk-Spreading So Unrealistic?

Oikos ◽  
1986 ◽  
Vol 47 (1) ◽  
pp. 114 ◽  
Author(s):  
Richard B. Root ◽  
Peter Kareiva
Keyword(s):  
Risk Spreading

Changes Over Time in Compassion-Related Variables in the United States

2017 ◽  
Author(s):  
Sasha Zarins ◽  
Sara Konrath
Keyword(s):  
United States ◽  
Emotional Response ◽  
The United States ◽  
Empathic Concern ◽  
Actual Data ◽  
Risk Spreading ◽  
Changes Over Time ◽  
Over Time

Compassion, or empathic concern, is an emotional response to another’s suffering, coupled with the desire to take action to alleviate that suffering. Throughout history, older generations have been critical of younger generations, often arguing that they are more self-focused than previous generations. However, it is important to examine actual data with respect to changes over time in such variables. Without doing so, we risk spreading potentially harmful and inaccurate stereotypes about young Americans. The goal of this chapter is to review research examining changes over time in compassion-related variables in the United States. Research suggests that compassion-related variables have indeed been declining over time, while self-focused variables have been increasing. However, we will also discuss counter-arguments and counter-evidence, and present possible implications of this research.

scholarly journals Prolonged diapause has sex-specific fertility and fitness costs

2019 ◽  
Vol 34 (1) ◽  
pp. 41-57 ◽  
Author(s):  
Aigi Margus ◽  
Leena Lindström
Keyword(s):  
Stress Tolerance ◽  
Adult Survival ◽  
Fitness Costs ◽  
Older Parents ◽  
Development Times ◽  
Risk Spreading ◽  
The Difference ◽  
Prolonged Diapause ◽  
Breeding Seasons ◽  
Diapause Duration

AbstractDiapause in seasonal environments allows insects to survive adverse seasons. However, individuals can sometimes enter a prolonged diapause for more than a year, and also skip favourable seasons, which can bring additional costs through e.g. loss of metabolic resources. At the same time, prolonged diapause can be beneficial if it allows individuals to have a risk-spreading strategy to skip potentially suboptimal breeding seasons. We studied if prolonged diapause (2-year diapause) negatively affects the fertility and fitness of female and male Colorado potato beetles (Leptinotarsa decemlineata) compared to control (1-year diapause) beetles. We also tested the parental effects on the subsequent chemical stress tolerance of their offspring. We found that prolonged diapause carried fertility costs only for females who were less fertile than the control females. However, no differences in fertility were observed in males. Furthermore, prolonged diapause in females resulted in offspring with lower larvae-to-adult survival even though these offspring had accelerated development times. In contrast, paternal diapause duration had no effects on their offspring larvae-to adult survival, but prolonged diapause males sired offspring with slower development times than control males. Perhaps to compensate the costs related to prolonged diapause both older parents produced or sired offspring with higher body mass than control parents. Despite the differences in emergence mass, parental diapause duration did not affect offspring insecticide stress tolerance. The difference between females and males most likely results from the observed differences in prolonged diapause females’ capacity to fight against cellular oxidative damage which was poorer compared to the control females. Even though prolonged diapause allows individuals to have a risk-spreading strategy it carries sex-specific fertility and fitness costs indicating that selection could favour this in males but not in females.

scholarly journals Detection of Potato mop-top virus in Potato Tubers and Sprouts: Combinations of RNA2 and RNA3 Variants and Incidence of Symptomless Infections

2009 ◽  
Vol 99 (5) ◽  
pp. 519-531 ◽  
Author(s):  
Satu Latvala-Kilby ◽  
Johanna M. Aura ◽  
Neda Pupola ◽  
Asko Hannukkala ◽  
Jari P. T. Valkonen
Keyword(s):  
Untranslated Region ◽  
Visual Inspection ◽  
Fragment Length Polymorphism ◽  
Enzyme Linked Immunosorbent Assay ◽  
Polymorphism Analysis ◽  
Potato Tubers ◽  
Chain Reaction ◽  
Risk Spreading ◽  
Polymerase Chain ◽  
Potato Mop Top Virus

Potato mop-top virus (PMTV, genus Pomovirus) causes severe quality problems by inducing necrotic arcs (spraing symptoms) in potato tubers. In this study, coat protein (CP) gene and read-through domain of RNA2 and 8K gene and 3′ untranslated region of RNA3 were characterized from 37 PMTV isolates detected in tubers from fields in Finland and a screenhouse in Latvia. Two distinguishable types of RNA2 and RNA3 were found, each showing only little genetic variability. Sequencing and restriction fragment length polymorphism analysis of polymerase chain reaction amplicons indicated that the majority of PMTV isolates infecting tubers comprise restrictotypes RNA2-II and RNA3-B. The incidence of PMTV-infected tubers in 2006 (2007) was 55 (60), 33 (39), and 62 (68)% in cvs. Kardal, Saturna, and Nicola, respectively, grown in the same field in 2006 (2007). Incidence of PMTV-infected tubers that were symptomless was 100 (90)% in Kardal and 88 (44)% in Saturna, and also high in cvs. Bintje (95%) and Van Gogh (63%), tested only in 2006, whereas it was only 12 (2)% in Nicola. Hence, reliance on visual inspection of spraing will miss a large proportion of infected tubers and risk spreading PMTV to new fields in seed tubers. No specific combination of the types of RNA2 and RNA3 was associated with spraing-expressing or symptomless tubers. Using recombinant PMTV CP for comparison, the concentrations of PMTV CP in tuber and sprout tissue were estimated to reach 57 μg/g. Sprout sap interfered less with enzyme-linked immunosorbent assay than did tuber sap.

Long-term persistence of agricultural pest insects by risk-spreading dispersal

2018 ◽  
Vol 33 (5) ◽  
pp. 1031-1037 ◽  
Author(s):  
Maica Krizna Areja Gavina ◽  
Kotaro Aoki ◽  
Genki Ichinose ◽  
Jomar Fajardo Rabajante ◽  
Hiromu Ito ◽  
...  
Keyword(s):  
Agricultural Pest ◽  
Pest Insects ◽  
Risk Spreading

Reducing Risk as well as Inequality: Assessing the Welfare State's Insurance Effects

2020 ◽  
pp. 1-11
Author(s):  
Jacob S. Hacker ◽  
Philipp Rehm
Keyword(s):  
Panel Data ◽  
Welfare State ◽  
Risk Reduction ◽  
Cross Section ◽  
Welfare States ◽  
Education Levels ◽  
Risk Spreading ◽  
Broad Cross Section ◽  
Over Time ◽  
The Welfare State

Abstract Leading accounts of the politics of the welfare state focus on societal demands for risk-spreading policies. Yet current measures of the welfare state focus not on risk, but on inequality. To address this gap, this letter describes the development of two new measures, risk incidence and risk reduction, which correspond to the prevalence of large income losses and the degree to which welfare states reduce that prevalence, respectively. Unlike existing indicators, these measures require panel data, which the authors harmonize for twenty-one democracies. The study finds that large losses affect all income and education levels, making the welfare state valuable to a broad cross-section of citizens. It also finds that taxes and transfers greatly reduce the prevalence of such losses, though to varying degrees across countries and over time. Finally, it disaggregates the measures to identify specific ‘triggers’ of large losses, and finds that these triggers are associated with risks on which welfare states focus, such as unemployment and sickness.

Risk-Spreading Properties of Common Tax and Contract Instruments

1982 ◽  
Vol 13 (2) ◽  
pp. 555 ◽  
Author(s):  
J. K. Sebenius ◽  
P. J. E. Stan
Keyword(s):  
Risk Spreading
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