scholarly journals The Architecture of Cooperation Among Non-kin: Coalitions to Move Up in Nature’s Housing Market

2021 ◽  
Vol 9 ◽  
Author(s):  
Mark E. Laidre

The evolution of cooperation among non-kin poses a major theoretical puzzle: why should natural selection favor individuals who help unrelated conspecifics at a cost to themselves? The relevance of architecture to this question has rarely been considered. Here I report cooperation among non-kin in social hermit crabs (Coenobita compressus), where unrelated conspecifics work together to evict larger individuals from a housing market of architecturally remodeled shells. I present (1) the first detailed description of natural coalitions in the wild and (2) a theoretical framework, which examines the evolutionary benefits to each coalition member and predicts when forming a coalition will be successful. In the wild, important ecological and social constraints exist, which are built into the model. Based on these constraints, I show that coalitions can be a successful strategy if several key criteria hold: the coalition is necessary, effective, stable dyadically, and stable polyadically. Notably, the “splitting the spoils” problem—which often undermines non-kin cooperation—is eliminated via architecture: a small individual (C) who helps a medium individual (B) to evict a large individual (A) will ultimately benefit, since C will get B’s left behind shell after B moves into A’s shell. Coalitions, however, can break down due to added layers of social complexity involving third-party “free riders” and “cheaters,” which strategically butt in the architectural queue and thereby steal incentives from the smaller coalition member. Overall, therefore, substantial scope exists for both cooperation and conflict within nature’s housing market of architecture. Experiments are now needed to directly test the impact on coalitions of architecture, from the interior of homes up to whole housing markets.

Author(s):  
Yinhai Fang ◽  
Tina P. Benko ◽  
Matjaž Perc ◽  
Haiyan Xu ◽  
Qingmei Tan

We study the evolution of cooperation in the spatial public goods game in the presence of third-party rewarding and punishment. The third party executes public intervention, punishing groups where cooperation is weak and rewarding groups where cooperation is strong. We consider four different scenarios to determine what works best for cooperation, in particular, neither rewarding nor punishment, only rewarding, only punishment or both rewarding and punishment. We observe strong synergistic effects when rewarding and punishment are simultaneously applied, which are absent if neither of the two incentives or just each individual incentive is applied by the third party. We find that public cooperation can be sustained at comparatively low third-party costs under adverse conditions, which is impossible if just positive or negative incentives are applied. We also examine the impact of defection tolerance and application frequency, showing that the higher the tolerance and the frequency of rewarding and punishment, the more cooperation thrives. Phase diagrams and characteristic spatial distributions of strategies are presented to corroborate these results, which will hopefully prove useful for more efficient public policies in support of cooperation in social dilemmas.


2019 ◽  
Vol 10 (2) ◽  
pp. 144-151
Author(s):  
Noora Ahmed Lari ◽  

The State of Qatar has implemented several family policies in order to improve the wellbeing of Qatari families and ensure fair distribution of development benefits for both men and women. However, there is a linkage between female employment outside the home and instability in the marriages of Qatari families. This paper investigates the impact of female employment on marital stability, based on the results of primary data collected in Qatar, a questionnaire that consisted of several sections such as challenges in the workplace, supervisor, family and spouse relations, work motivation and performance. Of the 824 questionnaires that were returned, 807 were completed and valid for analysis. Regression analysis and an ANOVA test have been used to test the relationship between the variables. The results of the research have produced mixed findings about how wives’ employment increases marital instability and have yielded few significant differences on mean scores of discuss on work demands, insufficient time together, housework, financial matters, communication, relatives and rearing children. The results indicates that in general Qatar working women face several challenges in relation to their marital life as part of cultural and social constraints.


Author(s):  
Lily N Edwards-Callaway ◽  
M Caitlin Cramer ◽  
Caitlin N Cadaret ◽  
Elizabeth J Bigler ◽  
Terry E Engle ◽  
...  

ABSTRACT Shade is a mechanism to reduce heat load providing cattle with an environment supportive of their welfare needs. Although heat stress has been extensively reviewed, researched, and addressed in dairy production systems, it has not been investigated in the same manner in the beef cattle supply chain. Like all animals, beef cattle are susceptible to heat stress if they are unable to dissipate heat during times of elevated ambient temperatures. There are many factors that impact heat stress susceptibility in beef cattle throughout the different supply chain sectors, many of which relate to the production system, i.e. availability of shade, microclimate of environment, and nutrition management. The results from studies evaluating the effects of shade on production and welfare are difficult to compare due to variation in structural design, construction materials used, height, shape, and area of shade provided. Additionally, depending on operation location, shade may or may not be beneficial during all times of the year, which can influence the decision to make shade a permanent part of management systems. Shade has been shown to lessen the physiologic response of cattle to heat stress. Shaded cattle exhibit lower respiration rates, body temperatures, and panting scores compared to un-shaded cattle in weather that increases the risk of heat stress. Results from studies investigating the provision of shade indicate that cattle seek shade in hot weather. The impact of shade on behavioral patterns is inconsistent in the current body of research, some studies indicating shade provision impacts behavior and other studies reporting no difference between shaded and un-shaded groups. Analysis of performance and carcass characteristics across feedlot studies demonstrated that shaded cattle had increased ADG, improved feed efficiency, HCW, and dressing percentage when compared to cattle without shade. Despite the documented benefits of shade, current industry statistics, although severely limited in scope, indicate low shade implementation rates in feedlots and data in other supply chain sectors do not exist. Industry guidelines and third party on-farm certification programs articulate the critical need for protection from extreme weather but are not consistent in providing specific recommendations and requirements. Future efforts should include: updated economic analyses of cost versus benefit of shade implementation, exploration of producer perspectives and needs relative to shade, consideration of shade impacts in the cow-calf and slaughter plant segments of the supply chain, and integration of indicators of affective (mental) state and preference in research studies to enhance the holistic assessment of cattle welfare.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Brian J. Johnson ◽  
Amy Robbins ◽  
Narayan Gyawali ◽  
Oselyne Ong ◽  
Joanne Loader ◽  
...  

AbstractKoala populations in many areas of Australia have declined sharply in response to habitat loss, disease and the effects of climate change. Koalas may face further morbidity from endemic mosquito-borne viruses, but the impact of such viruses is currently unknown. Few seroprevalence studies in the wild exist and little is known of the determinants of exposure. Here, we exploited a large, spatially and temporally explicit koala survey to define the intensity of Ross River Virus (RRV) exposure in koalas residing in urban coastal environments in southeast Queensland, Australia. We demonstrate that RRV exposure in koalas is much higher (> 80%) than reported in other sero-surveys and that exposure is uniform across the urban coastal landscape. Uniformity in exposure is related to the presence of the major RRV mosquito vector, Culex annulirostris, and similarities in animal movement, tree use, and age-dependent increases in exposure risk. Elevated exposure ultimately appears to result from the confinement of remaining coastal koala habitat to the edges of permanent wetlands unsuitable for urban development and which produce large numbers of competent mosquito vectors. The results further illustrate that koalas and other RRV-susceptible vertebrates may serve as useful sentinels of human urban exposure in endemic areas.


Land ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 596
Author(s):  
Shinichi Kitano

Abandoned farmland is particularly problematic in developed countries where agriculture has a comparative disadvantage in terms of effective use of land resources invested over time. While many studies have estimated the causes of these problems, few have discussed in detail the impact of data characteristics and accuracy on the estimation results. In this study, issues related to the underlying data and the estimation of the determinants of farmland abandonment were examined. Most previous studies on farmland abandonment in Japan have used census data as the basis of their analyses. However, census data are recorded subjectively by farmers. To address this, surveys of abandoned farmland are being conducted by a third party, and the results are compiled into a geographic information system (GIS) database. Two types of datasets (subjective census data and objective GIS data) were examined for their estimation performance. Although the two sets of data are correlated, there are considerable differences between them. Subjective variables are compatible with subjective data, and objective variables are compatible with objective data (meaning that parameters are easily identified). Original data for analysis, such as policy variables, are compatible with objective data. In policy evaluation research, attention should be paid to objective data collection.


Author(s):  
Paula Schirrmacher ◽  
Christina C. Roggatz ◽  
David M. Benoit ◽  
Jörg D. Hardege

AbstractWith carbon dioxide (CO2) levels rising dramatically, climate change threatens marine environments. Due to increasing CO2 concentrations in the ocean, pH levels are expected to drop by 0.4 units by the end of the century. There is an urgent need to understand the impact of ocean acidification on chemical-ecological processes. To date, the extent and mechanisms by which the decreasing ocean pH influences chemical communication are unclear. Combining behaviour assays with computational chemistry, we explore the function of the predator related cue 2-phenylethylamine (PEA) for hermit crabs (Pagurus bernhardus) in current and end-of-the-century oceanic pH. Living in intertidal environments, hermit crabs face large pH fluctuations in their current habitat in addition to climate-change related ocean acidification. We demonstrate that the dietary predator cue PEA for mammals and sea lampreys is an attractant for hermit crabs, with the potency of the cue increasing with decreasing pH levels. In order to explain this increased potency, we assess changes to PEA’s conformational and charge-related properties as one potential mechanistic pathway. Using quantum chemical calculations validated by NMR spectroscopy, we characterise the different protonation states of PEA in water. We show how protonation of PEA could affect receptor-ligand binding, using a possible model receptor for PEA (human TAAR1). Investigating potential mechanisms of pH-dependent effects on olfactory perception of PEA and the respective behavioural response, our study advances the understanding of how ocean acidification interferes with the sense of smell and thereby might impact essential ecological interactions in marine ecosystems.


2020 ◽  
pp. 019459982096963
Author(s):  
Vanessa F. Torrecillas ◽  
Kaden Neuberger ◽  
Alexander Ramirez ◽  
Paul Krakovitz ◽  
Jeremy D. Meier

Objective Third-party payers advocate for prior authorization (PA) to reduce overutilization of health care resources. The impact of PA in elective surgery is understudied, especially in cases where evidence-based clinical practice guidelines define operative candidacy. The objective of this study is to investigate the impact of PA on the incidence of pediatric tonsillectomy. Study Design Cross-sectional study. Setting Health claims database from a third-party payer. Methods Any pediatric patient who had evaluation for tonsillectomy from 2016 to 2019 was eligible for inclusion. A time series analysis was used to evaluate the change in incidence of tonsillectomy before and after PA. Lag time from consultation to surgery before and after PA was compared with segmented regression. Results A total of 10,047 tonsillectomy claims met inclusion and exclusion criteria. Female patients made up 51% of claims, and the mean age was 7.9 years. Just 1.5% of claims were denied after PA implementation. There was no change in the incidence of tonsillectomy for all plan types ( P = .1). Increased lag time from consultation to surgery was noted immediately after PA implementation by 2.38 days (95% CI, 0.23-4.54; P = .030); otherwise, there was no significant change over time ( P = .98). Conclusion A modest number of tonsillectomy claims were denied approval after implementation of PA. The value of PA for pediatric tonsillectomy is questionable, as it did not result in decreased incidence of tonsillectomy in this cohort.


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