scholarly journals Avoidance of Contaminated Food Correlates With Low Protozoan Infection in Bonobos

2021 ◽  
Vol 9 ◽  
Author(s):  
Cécile Sarabian ◽  
Raphaël Belais ◽  
Andrew J. J. MacIntosh

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.

2021 ◽  
Vol 9 ◽  
Author(s):  
Abel Bernadou ◽  
Boris H. Kramer ◽  
Judith Korb

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.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zahra Barakchian ◽  
Anjali Raja Beharelle ◽  
Todd A. Hare

AbstractFood choice paradigms are commonly used to study decision mechanisms, individual differences, and intervention efficacy. Here, we measured behavior from twenty-three healthy young adults who completed five repetitions of a cued-attribute food choice paradigm over two weeks. This task includes cues prompting participants to explicitly consider the healthiness of the food items before making a selection, or to choose naturally based on whatever freely comes to mind. We found that the average patterns of food choices following both cue types and ratings about the palatability (i.e. taste) and healthiness of the food items were similar across all five repetitions. At the individual level, the test-retest reliability for choices in both conditions and healthiness ratings was excellent. However, test-retest reliability for taste ratings was only fair, suggesting that estimates about palatability may vary more from day to day for the same individual.


1982 ◽  
Vol 4 (4) ◽  
pp. 105-111
Author(s):  
Lance Chilton

Hepatitis A is a common disease in children, usually passed by the fecal-oral route. Because of its route of transmission, day care centers, especially those caring for infants and toddlers in diapers, are a likely site of passage of the disease, unlike schools, where transfer of HAV occurs uncommonly. The pediatrician encountering a case of HA must ascertain (1) that other possible aiagnoses have been eliminated, (2) whether the patient or a sibling attends a day care center, and (3) the likelihood of a common source outbreak associated with contaminated food or drink. Public health help should be sought to determine that all wider implications of the patient's disease have been taken into account. In some instances, immunoglobulin use may be indicated beyond the usual group of family and sexual contacts. In many cases, the pediatrician will be asked to stretch the indications for immunoglobulin prophylaxis; the forces may be so strong as to force mass immunoglobulin administration even if inschool transmission is unlikely. There is no specific treatment for hepatitis; previously prescribed diets and restrictions of activity are unnecessary. Recovery without complications occurs in the vast majority of patients, especially children, with HA. Hepatitis B and non-A, non-B hepatitis are less common than HA in children, except those in certain groups. Those infected have a 10% likelihood of contracting chronic active hepatitis; with HB, a chronic carrier state contributes substantially to the epidemiology of the disease. The same is likely to hold true for non-A, non-B hepatitis. In patients with needle-stick, blood product, or sexual xposure to HB, standard immunoglobulin or HBIG is recommended as prophylaxis; for those exposed to NANB, immunoglobulin may be given. A vaccine to give active protection against HB exists; one is being developed for HA as well.


Author(s):  
Joshua Simmons ◽  
Kristen Splinter

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


Genetics ◽  
1980 ◽  
Vol 96 (1) ◽  
pp. 263-273
Author(s):  
Robert E Page

ABSTRACT A model is presented showing that natural selection operating at the individual level can adequately explain the evolution of multiple mating behavior by honey bee queens. Group selection need not be invoked. The fitness of a given female genotype is a function of the number of sex alleles in the population, the number of matings by an individual female and the specific parameters that determine the relationship of brood viability to individual fitness. Even though the exact relationship is not known, it is almost certainly not linear. A nonlinear relationship between worker brood viability and fitness and a significant genetic load associated with the sex-determination system in honey bees are the essential components of this model.


eLife ◽  
2022 ◽  
Vol 11 ◽  
Author(s):  
Hala Tamim El Jarkass ◽  
Calvin Mok ◽  
Michael R Schertzberg ◽  
Andrew G Fraser ◽  
Emily R Troemel ◽  
...  

Microsporidia are ubiquitous obligate intracellular pathogens of animals. These parasites often infect hosts through an oral route, but little is known about the function of host intestinal proteins that facilitate microsporidia invasion. To identify such factors necessary for infection by Nematocida parisii, a natural microsporidian pathogen of Caenorhabditis elegans, we performed a forward genetic screen to identify mutant animals that have a Fitness Advantage with Nematocida (Fawn). We isolated four fawn mutants that are resistant to Nematocida infection and contain mutations in T14E8.4, which we renamed aaim-1 (Antibacterial and Aids invasion by Microsporidia). Expression of AAIM-1 in the intestine of aaim-1 animals restores N. parisii infectivity and this rescue of infectivity is dependent upon AAIM-1 secretion. N. parisii spores in aaim-1 animals are improperly oriented in the intestinal lumen, leading to reduced levels of parasite invasion. Conversely, aaim-1 mutants display both increased colonization and susceptibility to the bacterial pathogen Pseudomonas aeruginosa and overexpression of AAIM-1 reduces P. aeruginosa colonization. Competitive fitness assays show that aaim-1 mutants are favoured in the presence of N. parisii but disadvantaged on P. aeruginosa compared to wild type animals. Together, this work demonstrates how microsporidia exploits a secreted protein to promote host invasion. Our results also suggest evolutionary trade-offs may exist to optimizing host defense against multiple classes of pathogens.


2021 ◽  
Author(s):  
Stephanie Marciniak ◽  
Christina Bergey ◽  
Ana Maria Silva ◽  
Agata Hałuszko ◽  
Mirosław Furmanek ◽  
...  

Human culture, biology, and health were shaped dramatically by the onset of agriculture ~12,000 years before present (BP). Subsistence shifts from hunting and gathering to agriculture are hypothesized to have resulted in increased individual fitness and population growth as evidenced by archaeological and population genomic data alongside a simultaneous decline in physiological health as inferred from paleopathological analyses and stature reconstructions of skeletal remains. A key component of the health decline inference is that relatively shorter statures observed for early farmers may (at least partly) reflect higher childhood disease burdens and poorer nutrition. However, while such stresses can indeed result in growth stunting, height is also highly heritable, and substantial inter-individual variation in the height genetic component within a population is typical. Moreover, extensive migration and gene flow were characteristics of multiple agricultural transitions worldwide. Here, we consider both osteological and ancient DNA data from the same prehistoric individuals to comprehensively study the trajectory of human stature variation as a proxy for health across a transition to agriculture. Specifically, we compared "predicted" genetic contributions to height from paleogenomic data and "achieved" adult osteological height estimated from long bone measurements on a per-individual basis for n=160 ancient Europeans from sites spanning the Upper Paleolithic to the Iron Age (~38,000-2,400 BP). We found that individuals from the Neolithic were shorter than expected (given their individual polygenic height scores) by an average of -4.47 cm relative to individuals from the Upper Paleolithic and Mesolithic (P=0.016). The average osteological vs. expected stature then increased relative to the Neolithic over the Copper (+2.67 cm, P=0.052), Bronze (+3.33 cm, P=0.032), and Iron Ages (+3.95 cm, P=0.094). These results were partly attenuated when we accounted for genome-wide genetic ancestry variation in our sample (which we note is partly duplicative with the individual polygenic score information). For example, in this secondary analysis Neolithic individuals were -3.48 cm shorter than expected on average relative to individuals from the Upper Paleolithic and Mesolithic (P=0.056). We also incorporated observations of paleopathological indicators of non-specific stress that can persist from childhood to adulthood in skeletal remains (linear enamel hypoplasia, cribra orbitalia, and porotic hyperostosis) into our model. Overall, our work highlights the potential of integrating disparate datasets to explore proxies of health in prehistory.


2012 ◽  
Vol 13 (4) ◽  
pp. 178 ◽  
Author(s):  
D Besada ◽  
G Van Cutsem ◽  
E Goemaere ◽  
N Ford ◽  
H Bygrave ◽  
...  

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+.


Author(s):  
Andy Gray ◽  
Jane Riddin ◽  
Richard Hain

Using medication in children’s palliative care (CPC) is fraught with difficulties as a result of an insufficient evidence-base and a lack of child friendly formulations, however this cannot be a reason not to intervene and allow unnecessary suffering. A lack of access in some countries to even essential medicines such as opioids is an infringement of the rights of the child to pain relief and needs urgent redress. Often, the only reasonable option is to extrapolate from adult data and to proceed rationally on the basis of what the prescriber knows about the available drug, the individual child, and the likely effects of their disease. Alternative routes for administration of medicines in children who are no longer able to use the oral route, such as the trans- and sub-cutaneous and buccal route mean symptom control can be provided at home and until end of life.


Author(s):  
Jaeyoung Jung ◽  
Joseph Y. J. Chow

With major investments in electric taxis emerging around the world, there is a need to better understand resource allocation trade-offs in subsidizing electric vehicle taxis (e-taxis) and investing in electric charging infrastructure. This is addressed using simulation experiments conducted in New York City: 2016 taxi pickups/drop-offs, a Manhattan road network (16,782 nodes, 23,337 links), and 212 charging stations specified by a 2013 Taxi & Limousine Commission study. The simulation is based on a platform used to evaluate taxi operations in California and Seoul. Eleven scenarios are analyzed: a baseline of 7,000 non-electric taxis, five scenarios ranging from 1,000 e-taxis to 5,000 e-taxis, and another five scenarios in which the e-taxis have infinite chargers as an upper bound. The study finds that the number of charging locations recommended in the earlier study may be insufficient at some locations even under the 3,000+ e-taxi scenarios. More importantly, despite an average revenue of $260 per taxi for the 7,000 non-electric taxis and about $247 per taxi for electric taxis over the finite charger scenarios, the revenue gap between e-taxis and non-electric taxis in a mixed fleet increases significantly as the e-taxi share increases. This is because the increasing queue delay imposed on e-taxis gives non-electric taxis an increasing competitive advantage, raising their average revenue from $260 per taxi (1,000 e-taxis) up to $286 per taxi (5,000 e-taxis, 150% revenue gap increase), all other operating costs being equal. This has implications for individual versus whole-fleet policies, as the individual-oriented policies may be less effective.


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