Resource allocation trade-offs in a mast-seeding conifer: Piñon pine prioritizes reproduction over defense

Abstract The cost of plant reproduction or defense at the expense of other fitness traits is a central component of life history theory. Yet the three central resource allocation pathways of growth, reproduction, and defense have rarely been assessed simultaneously nor across individual to landscape scales. This information is critical towards identifying the physiological, environmental, and genetic mechanisms underpinning resource allocation. This study assessed trade-offs in resource allocation between tree growth, defense, and reproduction across scales among piñon pine (Pinusedulis), a widespread mast-seeding conifer of the southwestern USA. Time series (2004-2016) of tree growth (radial and primary shoot growth), defense (resin duct production; a key constitutive defense for this species), and cone production among individual trees from populations across a broad environmental gradient were used to investigate these trade-offs in resource allocation across three scales: individual, population, and landscape. We found evidence for a defense-reproduction trade-off among individuals whereby total resin duct area in annual xylem rings was lower during years of above average cone production. Despite variability in cone and resin duct production across trees within a population and across populations, there was no association between these fitness traits at either of those scales. There was no evidence of trade-offs between cone production and growth at any scales measured, whereas resin duct production and growth were positively related at all scales. Our study suggests that a strategic trade-off occurs whereby investment into defense is temporarily curtailed to favor reproduction, despite increased risk of exposure to natural enemies and the ability of piñon pine to simultaneously allocate carbon to growth and defense. Our study provides new insights into physiological expressions of growth, defense, and reproduction over time in this long-lived masting conifer and indicates the presence of trade-offs with direct importance for individual fitness and population dynamics under global change.

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A hierarchical Bayesian model to investigate trade-offs between growth and reproduction in a long-lived plant

10.1101/2021.01.26.428205 ◽

2021 ◽

Author(s):

Valentin Journé ◽

Julien Papaïx ◽

Emily Walker ◽

François Courbet ◽

François Lefèvre ◽

...

Keyword(s):

Resource Allocation ◽

Late Stage ◽

Bayesian Model ◽

Low Density ◽

Hierarchical Bayesian Model ◽

Trade Off ◽

Trade Offs ◽

Individual Strategies ◽

Density Population ◽

Growth And Reproduction

1AbstractA trade-off between growth and fecundity, reflecting the inability of simultaneously investing in both functions when resources are limited, is a fundamental feature of life history theory. This particular trade-off is the result of evolutionary and environmental constrains shaping reproductive and growth traits, but it remains difficult to pinpoint in natural populations of long-lived plants. We developed a hierarchical Bayesian model to estimate the inter-individual correlation among growth and reproduction, using observations at individual level over several years combined with resource simulations from an ecophysiological-based model (CASTANEA). In the Bayesian model, the resource, simulated by CASTANEA and incorporated as a latent variable, is allocated to tree growth, reproductive buds initiation and fruit maturation. Then, we used individual random effects correlated among energetic sinks to investigate potential trade-offs. We applied this original approach to a Mediterranean coniferous tree, Atlas Cedar (Cedrus atlantica), at two contrasted levels of competition, high versus low density population. We found that trees initializing many reproductive buds had a higher growth. Moreover, a negative correlation was detected between growth and fruit survival during maturation. Finally, trees investing more resource to maturate fruits initiated less reproductive buds. The level of competition did not impact the sign of these three correlations, but changed the level of resource allocation: low density population favored growth whereas high density favored reproduction. The level of resource have an impact on individual strategies. This new modeling framework allowed us to detect various individual strategies of resource allocation to growth versus late-stage reproduction on the one hand, and to early-versus late-stage reproduction on the other hand. Moreover, the sign of the correlation between growth and reproductive traits depends on the stage of reproduction considered. Hence, we suggest that the investigation of potential trade-offs between growth and reproduction requires to integrate the dynamics of resource and sink’s phenology, from initiation to maturation of reproductive organs.

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Telomeres positively correlate with pace-of-life and elongate with age in a wild mammal

10.22541/au.163421567.77547120/v1 ◽

2021 ◽

Author(s):

Mathilde Tissier ◽

Patrick Bergeron ◽

Dany Garant ◽

Sandrine Zahn ◽

Francois Criscuolo ◽

...

Keyword(s):

Resource Allocation ◽

Life History ◽

Life Histories ◽

Life History Strategies ◽

Trade Off ◽

Pace Of Life ◽

Trade Offs ◽

Proactive Behaviour ◽

Anti Cancer ◽

Fast Pace

Understanding ageing and the diversity of life histories is a cornerstone in biology. Telomeres, the protecting caps of chromosomes, are thought to be involved in ageing, cancer risks and to modulate life-history strategies. They shorten with cell division and age in somatic tissues of most species, possibly limiting lifespan. The resource allocation trade-off hypothesis predicts that short telomeres have thus co-evolved with early reproduction, proactive behaviour and reduced lifespan, i.e. a fast Pace-of-Life Syndrome (POLS). Conversely, since short telomeres may also reduce the risks of cancer, the anti-cancer hypothesis advances that they should be associated with slow POLS. Conclusion on which hypothesis best supports the role of telomeres as mediators of life-history strategies is hampered by a lack of study on wild short-lived vertebrates, apart from birds. Using seven years of data on wild Eastern chipmunks Tamias striatus, we highlighted that telomeres elongate with age and do not limit lifespan in this species. Furthermore, short telomeres correlated with a slow POLS in a sex-specific way. Females with short telomeres had a delayed age at first breeding and a lower fecundity rate than females with long telomeres, whereas those differences were not recorded in males. Our findings support most predictions adapted from the anti-cancer hypothesis, but none of those made under the resource allocation trade-off hypothesis. Results are in line with an increasing body of evidence suggesting that resource allocation trade-offs alone cannot explaining the diversity of telomere length in adult somatic cells and life-histories observed across the tree of life.

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Resource allocation during ontogeny is influenced by genetic, developmental and ecological factors in the horned beetle, Onthophagus taurus

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2014.1625 ◽

2014 ◽

Vol 281 (1793) ◽

pp. 20141625 ◽

Cited By ~ 6

Author(s):

Daniel B. Schwab ◽

Armin P. Moczek

Keyword(s):

Resource Allocation ◽

Natural Populations ◽

Ecological Factors ◽

Developmental Genetic ◽

Trade Off ◽

Ecological Conditions ◽

Genetic Manipulations ◽

Onthophagus Taurus ◽

Trade Offs ◽

Horned Beetle

Resource allocation trade-offs arise when developing organs are in competition for a limited pool of resources to sustain growth and differentiation. Such competition may constrain the maximal size to which structures can grow and may force a situation in which the evolutionary elaboration of one structure may only be possible at the expense of another. However, recent studies have called into question both the consistency and evolutionary importance of resource allocation trade-offs. This study focuses on a well-described trade-off between the horns and eyes of Onthophagus beetles and assesses the degree to which it is influenced by genetic, developmental and ecological conditions. Contrary to expectations, we observed that trade-off signatures (i) were mostly absent within natural populations, (ii) mostly failed to match naturally evolved divergences in horn investment among populations, (iii) were subject to differential changes in F 1 populations derived from divergent field populations and (iv) remained largely unaffected by developmental genetic manipulations of horn investment. Collectively, our results demonstrate that populations subject to different ecological conditions exhibit different patterns of, and differential plasticity in, resource allocation. Further, variation in ecological conditions, rather than canalized developmental mechanisms, may determine whether and to what degree morphological structures engage in resource allocation trade-offs.

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Dual Goals for Speed and Accuracy on the Same Performance Task

Journal of Personnel Psychology ◽

10.1027/1866-5888/a000063 ◽

2012 ◽

Vol 11 (3) ◽

pp. 118-126 ◽

Cited By ~ 3

Author(s):

Olive Emil Wetter ◽

Jürgen Wegge ◽

Klaus Jonas ◽

Klaus-Helmut Schmidt

Keyword(s):

Memory Scanning ◽

Performance Task ◽

Performance Tasks ◽

Trade Off ◽

Test Experiment ◽

Trade Offs ◽

New Finding ◽

Sternberg Paradigm ◽

Speed Accuracy ◽

Speed And Accuracy

In most work contexts, several performance goals coexist, and conflicts between them and trade-offs can occur. Our paper is the first to contrast a dual goal for speed and accuracy with a single goal for speed on the same task. The Sternberg paradigm (Experiment 1, n = 57) and the d2 test (Experiment 2, n = 19) were used as performance tasks. Speed measures and errors revealed in both experiments that dual as well as single goals increase performance by enhancing memory scanning. However, the single speed goal triggered a speed-accuracy trade-off, favoring speed over accuracy, whereas this was not the case with the dual goal. In difficult trials, dual goals slowed down scanning processes again so that errors could be prevented. This new finding is particularly relevant for security domains, where both aspects have to be managed simultaneously.

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The Effects of Decision Time on Perceptions of Decisions and Decision Makers in (Moral) Trade-Off Scenarios

10.31234/osf.io/37t2r ◽

2019 ◽

Author(s):

Anna Katharina Spälti ◽

Mark John Brandt ◽

Marcel Zeelenberg

Keyword(s):

Decision Process ◽

Decision Time ◽

Decision Makers ◽

Process Information ◽

Total N ◽

Trade Off ◽

Financial Gain ◽

Trade Offs ◽

Sacred Values ◽

Moral Context

People often have to make trade-offs. We study three types of trade-offs: 1) "secular trade-offs" where no moral or sacred values are at stake, 2) "taboo trade-offs" where sacred values are pitted against financial gain, and 3) "tragic trade-offs" where sacred values are pitted against other sacred values. Previous research (Critcher et al., 2011; Tetlock et al., 2000) demonstrated that tragic and taboo trade-offs are not only evaluated by their outcomes, but are also evaluated based on the time it took to make the choice. We investigate two outstanding questions: 1) whether the effect of decision time differs for evaluations of decisions compared to decision makers and 2) whether moral contexts are unique in their ability to influence character evaluations through decision process information. In two experiments (total N = 1434) we find that decision time affects character evaluations, but not evaluations of the decision itself. There were no significant differences between tragic trade-offs and secular trade-offs, suggesting that the decisions structure may be more important in evaluations than moral context. Additionally, the magnitude of the effect of decision time shows us that decision time, may be of less practical use than expected. We thus urge, to take a closer examination of the processes underlying decision time and its perception.

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Predicting Undesired Treatment Outcome in Mental Healthcare: Machine Learning Study (Preprint)

10.2196/preprints.17235 ◽

2019 ◽

Author(s):

Kasper Van Mens ◽

Joran Lokkerbol ◽

Richard Janssen ◽

Robert de Lange ◽

Bea Tiemens

Keyword(s):

Machine Learning ◽

Treatment Outcome ◽

Mental Health Treatment ◽

Mental Healthcare ◽

Machine Learning Algorithms ◽

Gradient Boosting ◽

Trade Off ◽

Trade Offs ◽

Outcome Monitoring ◽

Extreme Gradient Boosting

BACKGROUND It remains a challenge to predict which treatment will work for which patient in mental healthcare. OBJECTIVE In this study we compare machine algorithms to predict during treatment which patients will not benefit from brief mental health treatment and present trade-offs that must be considered before an algorithm can be used in clinical practice. METHODS Using an anonymized dataset containing routine outcome monitoring data from a mental healthcare organization in the Netherlands (n = 2,655), we applied three machine learning algorithms to predict treatment outcome. The algorithms were internally validated with cross-validation on a training sample (n = 1,860) and externally validated on an unseen test sample (n = 795). RESULTS The performance of the three algorithms did not significantly differ on the test set. With a default classification cut-off at 0.5 predicted probability, the extreme gradient boosting algorithm showed the highest positive predictive value (ppv) of 0.71(0.61 – 0.77) with a sensitivity of 0.35 (0.29 – 0.41) and area under the curve of 0.78. A trade-off can be made between ppv and sensitivity by choosing different cut-off probabilities. With a cut-off at 0.63, the ppv increased to 0.87 and the sensitivity dropped to 0.17. With a cut-off of at 0.38, the ppv decreased to 0.61 and the sensitivity increased to 0.57. CONCLUSIONS Machine learning can be used to predict treatment outcomes based on routine monitoring data.This allows practitioners to choose their own trade-off between being selective and more certain versus inclusive and less certain.

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Challenges in the Empirical Study of Global Governance Legitimacy

10.1093/oso/9780198826873.003.0011 ◽

2018 ◽

Cited By ~ 1

Author(s):

Steven Bernstein

Keyword(s):

Empirical Study ◽

Global Governance ◽

Research Agenda ◽

Cultural Factors ◽

Theory Building ◽

Trade Off ◽

Trade Offs ◽

Different Types ◽

Political Communities

This commentary discusses three challenges for the promising and ambitious research agenda outlined in the volume. First, it interrogates the volume’s attempts to differentiate political communities of legitimation, which may vary widely in composition, power, and relevance across institutions and geographies, with important implications not only for who matters, but also for what gets legitimated, and with what consequences. Second, it examines avenues to overcome possible trade-offs from gains in empirical tractability achieved through the volume’s focus on actor beliefs and strategies. One such trade-off is less attention to evolving norms and cultural factors that may underpin actors’ expectations about what legitimacy requires. Third, it addresses the challenge of theory building that can link legitimacy sources, (de)legitimation practices, audiences, and consequences of legitimacy across different types of institutions.

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Biosecurity and Public Health Ethics Issues Raised by Biological Threats

The Oxford Handbook of Public Health Ethics ◽

10.1093/oxfordhb/9780190245191.013.67 ◽

2019 ◽

pp. 773-785

Author(s):

Nicholas Evans ◽

Thomas Inglesby

Keyword(s):

Public Health ◽

Resource Allocation ◽

Infectious Diseases ◽

Ethical Issues ◽

Emerging Infectious Diseases ◽

Biological Weapon ◽

Ethical Values ◽

Dual Use ◽

Health Concerns ◽

Trade Offs

This chapter introduces ethical issues that arise in the context of biosecurity: policies and actions intended to prevent the development or emergence, or mitigate the consequences, of serious biological threats. These threats could include deliberate biological weapon attacks (bioterrorism), pandemics, emerging infectious diseases, or major laboratory accidents. The basic values that underpin these public health concerns are first introduced. Ethical issues that arise before, during, and following a biosecurity crisis are then examined, including issues of resource allocation, dual-use research, and the possibility of quarantine. Their resolution requires trade-offs among different ethical values, including utility, fairness, and liberty.

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Toward Inclusive Landscape Governance in Contested Landscapes: Exploring the Contribution of Participatory Tools in the Upper Suriname River Basin

Environmental Management ◽

10.1007/s00267-021-01504-8 ◽

2021 ◽

Author(s):

Lisa Best ◽

Kimberley Fung-Loy ◽

Nafiesa Ilahibaks ◽

Sara O. I. Ramirez-Gomez ◽

Erika N. Speelman

Keyword(s):

Land Use ◽

River Basin ◽

Scenario Planning ◽

Community Members ◽

Trade Off ◽

3 Dimensional ◽

Landscape Governance ◽

Information Tools ◽

Tribal Communities ◽

Trade Offs

AbstractNowadays, tropical forest landscapes are commonly characterized by a multitude of interacting institutions and actors with competing land-use interests. In these settings, indigenous and tribal communities are often marginalized in landscape-level decision making. Inclusive landscape governance inherently integrates diverse knowledge systems, including those of indigenous and tribal communities. Increasingly, geo-information tools are recognized as appropriate tools to integrate diverse interests and legitimize the voices, values, and knowledge of indigenous and tribal communities in landscape governance. In this paper, we present the contribution of the integrated application of three participatory geo-information tools to inclusive landscape governance in the Upper Suriname River Basin in Suriname: (i) Participatory 3-Dimensional Modelling, (ii) the Trade-off! game, and (iii) participatory scenario planning. The participatory 3-dimensional modelling enabled easy participation of community members, documentation of traditional, tacit knowledge and social learning. The Trade-off! game stimulated capacity building and understanding of land-use trade-offs. The participatory scenario planning exercise helped landscape actors to reflect on their own and others’ desired futures while building consensus. Our results emphasize the importance of systematically considering tool attributes and key factors, such as facilitation, for participatory geo-information tools to be optimally used and fit with local contexts. The results also show how combining the tools helped to build momentum and led to diverse yet complementary insights, thereby demonstrating the benefits of integrating multiple tools to address inclusive landscape governance issues.

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On the effectiveness of tracking and testing in SEIR models for improving health vs. economy trade-offs

Scientific Reports ◽

10.1038/s41598-021-95415-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yoav Kolumbus ◽

Noam Nisan

Keyword(s):

Additional Parameter ◽

Patient Privacy ◽

Economic Costs ◽

Trade Off ◽

Seir Model ◽

Social Question ◽

Social Distancing ◽

Trade Offs ◽

Asymptomatic Individuals ◽

Testing Policies

AbstractWe study the effectiveness of tracking and testing policies for suppressing epidemic outbreaks. We evaluate the performance of tracking-based intervention methods on a network SEIR model, which we augment with an additional parameter to model pre-symptomatic and asymptomatic individuals, and study the effectiveness of these methods in combination with or as an alternative to quarantine and global lockdown policies. Our focus is on the basic trade-off between human-lives lost and economic costs, and on how this trade-off changes under different quarantine, lockdown, tracking, and testing policies. Our main findings are as follows: (1) Tests combined with patient quarantines reduce both economic costs and mortality, however, an extensive-scale testing capacity is required to achieve a significant improvement. (2) Tracking significantly reduces both economic costs and mortality. (3) Tracking combined with a moderate testing capacity can achieve containment without lockdowns. (4) In the presence of a flow of new incoming infections, dynamic “On–Off” lockdowns are more efficient than fixed lockdowns. In this setting as well, tracking strictly improves efficiency. The results show the extreme usefulness of policies that combine tracking and testing for reducing mortality and economic costs, and their potential to contain outbreaks without imposing any social distancing restrictions. This highlights the difficult social question of trading-off these gains against patient privacy, which is inevitably infringed by tracking.

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