Evolution of trust and trustworthiness: social awareness favours personality differences

Interest in the evolution and maintenance of personality is burgeoning. Individuals of diverse animal species differ in their aggressiveness, fearfulness, sociability and activity. Strong trade-offs, mutation–selection balance, spatio-temporal fluctuations in selection, frequency dependence and good-genes mate choice are invoked to explain heritable personality variation, yet for continuous behavioural traits, it remains unclear which selective force is likely to maintain distinct polymorphisms. Using a model of trust and cooperation, we show how allowing individuals to monitor each other's cooperative tendencies, at a cost, can select for heritable polymorphisms in trustworthiness. This variation, in turn, favours costly ‘social awareness’ in some individuals. Feedback of this sort can explain the individual differences in trust and trustworthiness so often documented by economists in experimental public goods games across a range of cultures. Our work adds to growing evidence that evolutionary game theorists can no longer afford to ignore the importance of real world inter-individual variation in their models.

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Passthrough+

Proceedings of the ACM on Computer Graphics and Interactive Techniques ◽

10.1145/3384540 ◽

2020 ◽

Vol 3 (1) ◽

pp. 1-17

Author(s):

Gaurav Chaurasia ◽

Arthur Nieuwoudt ◽

Alexandru-Eugen Ichim ◽

Richard Szeliski ◽

Alexander Sorkine-Hornung

Keyword(s):

Real Time ◽

Video Encoding ◽

View Synthesis ◽

Performance Constraints ◽

Trade Offs ◽

Stereoscopic View ◽

Target User ◽

Spatio Temporal ◽

And Performance ◽

3D Scene

We present an end-to-end system for real-time environment capture, 3D reconstruction, and stereoscopic view synthesis on a mobile VR headset. Our solution allows the user to use the cameras on their VR headset as their eyes to see and interact with the real world while still wearing their headset, a feature often referred to as Passthrough. The central challenge when building such a system is the choice and implementation of algorithms under the strict compute, power, and performance constraints imposed by the target user experience and mobile platform. A key contribution of this paper is a complete description of a corresponding system that performs temporally stable passthrough rendering at 72 Hz with only 200 mW power consumption on a mobile Snapdragon 835 platform. Our algorithmic contributions for enabling this performance include the computation of a coarse 3D scene proxy on the embedded video encoding hardware, followed by a depth densification and filtering step, and finally stereoscopic texturing and spatio-temporal up-sampling. We provide a detailed discussion and evaluation of the challenges we encountered, as well as algorithm and performance trade-offs in terms of compute and resulting passthrough quality.;AB@The described system is available to users as the Passthrough+ feature on Oculus Quest. We believe that by publishing the underlying system and methods, we provide valuable insights to the community on how to design and implement real-time environment sensing and rendering on heavily resource constrained hardware.

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Holocene changes in African vegetation: tradeoff between climate and water availability

Climate of the Past ◽

10.5194/cp-10-681-2014 ◽

2014 ◽

Vol 10 (2) ◽

pp. 681-686 ◽

Cited By ~ 63

Author(s):

C. Hély ◽

A.-M. Lézine ◽

APD contributors

Keyword(s):

West Africa ◽

Water Availability ◽

Regional Scale ◽

Plant Distribution ◽

Climate Conditions ◽

Tropical Plants ◽

Plant Migration ◽

Spatio Temporal ◽

The Individual ◽

Instrumental Records

Abstract. Although past climate change is well documented in West Africa through instrumental records, modeling activities, and paleo-data, little is known about regional-scale ecosystem vulnerability and long-term impacts of climate on plant distribution and biodiversity. Here we use paleohydrological and paleobotanical data to discuss the relation between available surface water, monsoon rainfall and vegetation distribution in West Africa during the Holocene. The individual patterns of plant migration or community shifts in latitude are explained by differences among tolerance limits of species to rainfall amount and seasonality. Using the probability density function methodology, we show here that the widespread development of lakes, wetlands and rivers at the time of the "Green Sahara" played an additional role in forming a network of topographically defined water availability, allowing for tropical plants to migrate north from 15 to 24° N (reached ca. 9 cal ka BP). The analysis of the spatio–temporal changes in biodiversity, through both pollen occurrence and richness, shows that the core of the tropical rainbelt associated with the Intertropical Convergence Zone was centered at 15–20° N during the early Holocene wet period, with comparatively drier/more seasonal climate conditions south of 15° N.

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THE SPACES OF MYTH IN KAZUO ISHIGURO’S THE REMAINS OF THE DAY: EXPLORING THE INTERSECTIONS OF MEMORY AND HISTORY

Ensemble ◽

10.37948/ensemble-2021-0202-a023 ◽

2021 ◽

Vol 2 (2) ◽

pp. 234-242

Author(s):

Medha Bhadra Chowdhury ◽

Keyword(s):

Identity Politics ◽

Cultural Beliefs ◽

Traditional Values ◽

Confined Space ◽

Spatial Dimensions ◽

Temporal Expressions ◽

Spatio Temporal ◽

Post War ◽

The Individual ◽

Historical Past

Kazuo Ishiguro’s The Remains of the Day (1989) reconstructs the experiences of an ageing butler, Stevens, trapped within the confined space of the house he has served in for many years. The contours of memory are drawn along the spatial dimensions of the house which serve as a space of contestation between traditional values and emergent cultural beliefs in the post-war period. Physical modifications on the architecture produce continuities and alterations within the subject, who inhabits the space. This paper seeks to explore the dynamics of remembering and forgetting which are determined by the sites of memory and which trace historical changes as well as shifts in identity politics in Ishiguro’s novel. The paper critically assesses the idea of space, its functional dimension and mythic commemoration in relation to a symbolic historical past. It examines the development of subjectivity through the expansion of memory embodied in material form and the complex relationship between history and myth-making, which complicates individual identity. This paper further proposes that these spatio-temporal expressions can be understood as not only confined to the individual but may be extended to the domain of public memory and contextualized in a post-war British cultural politics of grief.

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Spatio-Temporal Gaussianization Flows for Extreme Event Detection

10.5194/egusphere-egu21-15729 ◽

2021 ◽

Author(s):

Miguel-Ángel Fernández-Torres ◽

J. Emmanuel Johnson ◽

María Piles ◽

Gustau Camps-Valls

Keyword(s):

Event Detection ◽

Land Surface ◽

Extreme Event ◽

Learning Approaches ◽

Proposed Model ◽

Individual Contributions ◽

Current Context ◽

Spatio Temporal ◽

The Individual ◽

Anomaly Score

<p>Automatic anticipation and detection of extreme events constitute a major challenge in the current context of climate change. Machine learning approaches have excelled in detection of extremes and anomalies in Earth data cubes recently, but are typically both computationally costly and supervised, which hamper their wide adoption. We alternatively present here an unsupervised, efficient, generative approach for extreme event detection, whose performance is illustrated for drought detection in Europe during the severe Russian heat wave in 2010. The core architecture of the model is generic and could naturally be extended to the detection of other kinds of anomalies. First, it computes hierarchical appearance (spatial) and motion (temporal) representations of several informative Essential Climate Variables (ECVs), including soil moisture, land surface temperature, as well as features describing vegetation health. Then, these representations are combined using Gaussianization Flows that yield a spatio-temporal anomaly score. This allows the proposed model not only to detect droughts areas, but also to explain why they were produced, monitoring the individual contributions of each of the ECVs to the indicator at its output.</p>

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COMBINING DATA-DRIVEN AND NUMERICAL MODELLING APPROACHES TO STORM EROSION PREDICTION

Coastal Engineering Proceedings ◽

10.9753/icce.v36v.sediment.38 ◽

2020 ◽

pp. 38

Author(s):

Joshua Simmons ◽

Kristen Splinter

Keyword(s):

Numerical Models ◽

Individual Performance ◽

Study Data ◽

Data Driven ◽

Erosion Prediction ◽

Trade Offs ◽

Combining Data ◽

Erosion Models ◽

Using Data ◽

The Individual

Physics-based numerical models play an important role in the estimation of storm erosion, particularly at beaches for which there is little historical data. However, the increasing availability of pre-and post-storm data for multiple events and at a number of beaches around the world has opened the possibility of using data-driven approaches for erosion prediction. Both physics-based and purely data-driven approaches have inherent strengths and weaknesses in their ability to predict storm-induced erosion. It is vital that coastal managers and modelers are aware of these trade-offs as well as methods to maximise the value from each modelling approach in an increasingly data-rich environment. In this study, data from approximately 40 years of coastal monitoring at Narrabeen-Collaroy Beach (SE Australia)has been used to evaluate the individual performance of the numerical erosion models SBEACH and XBeach, and a data-driven modelling technique. The models are then combined using a simple weighting technique to provide a hybrid estimate of erosion.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/v53dZiO8Y60

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Avoidance of Contaminated Food Correlates With Low Protozoan Infection in Bonobos

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.651159 ◽

2021 ◽

Vol 9 ◽

Author(s):

Cécile Sarabian ◽

Raphaël Belais ◽

Andrew J. J. MacIntosh

Keyword(s):

Infectious Agent ◽

Oral Route ◽

Behavioral Experiments ◽

Food Items ◽

Individual Fitness ◽

Behavioral Adaptations ◽

Trade Offs ◽

Protozoan Infection ◽

Contaminated Food ◽

The Individual

Intense selection pressure from parasites on free-living animals has resulted in behavioral adaptations that help potential hosts avoid sources of infection. In primates, such “behavioral immunity” is expressed in different contexts and may vary according to the ecology of the host, the nature of the infectious agent, and the individual itself. In this study, we investigated whether avoidance of contaminated food was associated with reduced parasite infection in sanctuary-housed bonobos. To do this, we used bonobos’ responses to soil- and fecally-contaminated food in behavioral experiments, and then compared the results with an estimate of protozoan infection across individuals. We found that avoidance of contaminated food correlated negatively with Balantioides coli infection, a potentially pathogenic protozoan transmitted through the fecal-oral route. The association between avoidance responses and parasitism were most evident in experiments in which subjects were offered a choice of food items falling along a gradient of fecal contamination. In the case of experiments with more limited options and a high degree of contamination, most subjects were averse to the presented food item and this may have mitigated any relationship between feeding decisions and infection. In experiments with low perceived levels of contamination, most subjects consumed previously contaminated food items, which may also have obscured such a relationship. The behavioral immunity observed may be a consequence of the direct effects of parasites (infection), reflecting the first scale of a landscape of disgust: individual responses. Indirect effects of parasites, such as modulation of feeding decisions and reduced social interactions—and their potential trade-offs with physiological immunity—are also discussed in light of individual fitness and primate evolution. This study builds on previous work by showing that avoidance behaviors may be effective in limiting exposure to a wide diversity of oro-fecally transmitted parasites.

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The effects of different frequencies of rhythmic acoustic stimulation on gait kinematics and trunk sway in healthy elderly population

10.1101/2020.11.20.390955 ◽

2020 ◽

Author(s):

Roberta Minino ◽

Emahnuel Troisi Lopez ◽

Pierpaolo Sorrentino ◽

Rosaria Rucco ◽

Anna Lardone ◽

...

Keyword(s):

Acoustic Stimulation ◽

Elderly Subjects ◽

Low Frequencies ◽

Healthy Elderly ◽

Gait Kinematics ◽

Trunk Sway ◽

Spatio Temporal ◽

The Individual ◽

Harmful Effects ◽

Healthy Elderly Subjects

ABSTRACTThe use of rhythmic acoustic stimulation (RAS) in improving gait and balance in healthy elderly subjects has been widely investigated. However, methodologies and results are often controversial. In this study, we hypothesize that both the kinematic features of gait and stability, depend on the frequency at which RAS is administered. Our aim was to observe, through 3D Gait Analysis, the effect of different types of RAS (at a fixed frequency or based on the average cadence of each subject) on both gait spatio-temporal parameters and stability. The latter was estimated through an innovative measure, the trunk displacement index (TDI) that we have recently implemented. We observed that the low frequencies RAS led to a general slowdown of gait, which did not provide any clear benefit and produced harmful effects on stability when the frequency became too low compared to the individual natural frequency. On the contrary, the high frequencies of RAS showed a slight acceleration of gait, accompanied by better stability (as documented by a lower TDI value), regardless of the type of RAS. Finally, the RAS equal to the individual natural cadence also produced an increase in stability.

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The case for Option B and Optional B+: Ensuring that South Africa’s commitment to eliminating mother-to-child transmission of HIV becomes a reality

Southern African Journal of HIV Medicine ◽

10.4102/sajhivmed.v13i4.112 ◽

2012 ◽

Vol 13 (4) ◽

pp. 178 ◽

Cited By ~ 3

Author(s):

D Besada ◽

G Van Cutsem ◽

E Goemaere ◽

N Ford ◽

H Bygrave ◽

...

Keyword(s):

South African ◽

Population Level ◽

World Health ◽

Mother To Child Transmission ◽

Child Transmission ◽

Trade Offs ◽

The Individual ◽

Mother To Child ◽

African Journal ◽

In Pregnancy

In a previous issue of the Southern African Journal of HIV Medicine, Pillay and Black summarised the trade-offs of the safety of efavirenz use in pregnancy (Pillay P, Black V. Safety, strength and simplicity of efavirenz in pregnancy. Southern African Journal of HIV Medicine 2012;13(1):28-33.). Highlighting the benefits of the World Health Organization’s proposed options for the prevention of mother-to-child transmission (PMTCT) of HIV, the authors argued that the South African government should adopt Option B as national PMTCT policy and pilot projects implementing Option B+ as a means of assessing the individual- and population-level effect of the intervention. We echo this call and further propose that the option to remain on lifelong antiretroviral therapy, effectively adopting PMTCT Option B+, be offered to pregnant women following the cessation of breastfeeding, for their own health, following the provision of counselling on associated benefits and risks. Here we highlight the benefits of Options B and B+.

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Major Evolutionary Transitions in Social Insects, the Importance of Worker Sterility and Life History Trade-Offs

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.732907 ◽

2021 ◽

Vol 9 ◽

Author(s):

Abel Bernadou ◽

Boris H. Kramer ◽

Judith Korb

Keyword(s):

Life History ◽

Social Insects ◽

Division Of Labour ◽

Evolutionary Transitions ◽

Individual Level ◽

Individual Fitness ◽

Trade Offs ◽

Group Members ◽

The Individual ◽

Worker Sterility

The evolution of eusociality in social insects, such as termites, ants, and some bees and wasps, has been regarded as a major evolutionary transition (MET). Yet, there is some debate whether all species qualify. Here, we argue that worker sterility is a decisive criterion to determine whether species have passed a MET (= superorganisms), or not. When workers are sterile, reproductive interests align among group members as individual fitness is transferred to the colony level. Division of labour among cooperating units is a major driver that favours the evolution of METs across all biological scales. Many METs are characterised by a differentiation into reproductive versus maintenance functions. In social insects, the queen specialises on reproduction while workers take over maintenance functions such as food provisioning. Such division of labour allows specialisation and it reshapes life history trade-offs among cooperating units. For instance, individuals within colonies of social insects can overcome the omnipresent fecundity/longevity trade-off, which limits reproductive success in organisms, when increased fecundity shortens lifespan. Social insect queens (particularly in superorganismal species) can reach adult lifespans of several decades and are among the most fecund terrestrial animals. The resulting enormous reproductive output may contribute to explain why some genera of social insects became so successful. Indeed, superorganismal ant lineages have more species than those that have not passed a MET. We conclude that the release from life history constraints at the individual level is a important, yet understudied, factor across METs to explain their evolutionary success.

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Machine learning as a successful approach for predicting complex spatio–temporal patterns in animal species abundance

Animal Biodiversity and Conservation ◽

10.32800/abc.2021.44.0289 ◽

2021 ◽

pp. 289-301

Author(s):

B. Martín ◽

J. González–Arias ◽

J. A. Vicente–Vírseda

Keyword(s):

Machine Learning ◽

Random Forest ◽

Animal Species ◽

Temporal Patterns ◽

Additive Models ◽

Gradient Boosting ◽

Support Vector ◽

Stochastic Gradient Boosting ◽

Extreme Gradient Boosting ◽

Spatio Temporal

Our aim was to identify an optimal analytical approach for accurately predicting complex spatio–temporal patterns in animal species distribution. We compared the performance of eight modelling techniques (generalized additive models, regression trees, bagged CART, k–nearest neighbors, stochastic gradient boosting, support vector machines, neural network, and random forest –enhanced form of bootstrap. We also performed extreme gradient boosting –an enhanced form of radiant boosting– to predict spatial patterns in abundance of migrating Balearic shearwaters based on data gathered within eBird. Derived from open–source datasets, proxies of frontal systems and ocean productivity domains that have been previously used to characterize the oceanographic habitats of seabirds were quantified, and then used as predictors in the models. The random forest model showed the best performance according to the parameters assessed (RMSE value and R2). The correlation between observed and predicted abundance with this model was also considerably high. This study shows that the combination of machine learning techniques and massive data provided by open data sources is a useful approach for identifying the long–term spatial–temporal distribution of species at regional spatial scales.

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