scholarly journals Compensatory and additive helper effects in the cooperatively breeding Seychelles warbler (Acrocephalus sechellensis)

2018 ◽  
Author(s):  
Lotte A. van Boheemen ◽  
Martijn Hammers ◽  
Sjouke A. Kingma ◽  
David S. Richardson ◽  
Terry Burke ◽  
...  
Keyword(s):  
Group Size ◽  
Food Availability ◽  
Dominant Male ◽  
List Type ◽  
Territory Quality ◽  
Trade Offs ◽  
Cooperatively Breeding ◽  
Helping Behaviour ◽  
Seychelles Warbler ◽  
The Impact

ABSTRACTIn cooperatively breeding species, helper aid may affect dominant breeders’ investment trade-offs between current and future reproduction. By compensating for the care provided by helpers, breeders can reduce the costs of reproduction and improve chances of survival. Also, helper care can be additive to that of dominants, resulting in higher success of the current brood.However, the influence of helpers on offspring care itself may be the by-product of group size and territory quality. Therefore to make conclusive inferences about causation of additive and compensatory care as a result of helpper serequires disentangling the impact of helping from other factors determining parental investment.In this study, we use 20 years of offspring provisioning data to investigate the effect of helping on breeder and overall offspring provisioning rates in the facultative cooperatively breeding Seychelles warbler (Acrocephalus sechellensis). Our extensive dataset allowed us to effectively control for the effects of living in a larger group and in territories with higher food availability.We show compensatory and additive care in response to helper aid. Helpers lightened the provisioning load of the dominant male and female and increased the total provisioning to the nestlings. This was irrespective of group size or territory quality (food availability).Our results illustrate how multiple benefits of helping behaviour can simultaneously be fundamental to the evolutionary maintenance of cooperative behaviour.

scholarly journals Socio-ecological conditions and female infidelity in the Seychelles warbler

2019 ◽  
Vol 30 (5) ◽  
pp. 1254-1264 ◽  
Author(s):  
Sara Raj Pant ◽  
Jan Komdeur ◽  
Terry A Burke ◽  
Hannah L Dugdale ◽  
David S Richardson
Keyword(s):  
Group Size ◽  
Breeding Systems ◽  
Dominant Male ◽  
Territory Quality ◽  
Ecological Conditions ◽  
Extra Pair Paternity ◽  
Socially Monogamous ◽  
Seychelles Warbler ◽  
Study Population ◽  
Female Infidelity

Abstract Within socially monogamous breeding systems, levels of extra-pair paternity can vary not only between species, populations, and individuals, but also across time. Uncovering how different extrinsic conditions (ecological, demographic, and social) influence this behavior will help shed light on the factors driving its evolution. Here, we simultaneously address multiple socio-ecological conditions potentially influencing female infidelity in a natural population of the cooperatively breeding Seychelles warbler, Acrocephalus sechellensis. Our contained study population has been monitored for more than 25 years, enabling us to capture variation in socio-ecological conditions between individuals and across time and to accurately assign parentage. We test hypotheses predicting the influence of territory quality, breeding density and synchrony, group size and composition (number and sex of subordinates), and inbreeding avoidance on female infidelity. We find that a larger group size promotes the likelihood of extra-pair paternity in offspring from both dominant and subordinate females, but this paternity is almost always gained by dominant males from outside the group (not by subordinate males within the group). Higher relatedness between a mother and the dominant male in her group also results in more extra-pair paternity—but only for subordinate females—and this does not prevent inbreeding occurring in this population. Our findings highlight the role of social conditions favoring infidelity and contribute toward understanding the evolution of this enigmatic behavior.

scholarly journals Hot droughts compromise interannual survival across all group sizes in a cooperatively breeding bird

2020 ◽  
Author(s):  
Amanda R. Bourne ◽  
Susan J. Cunningham ◽  
Claire N. Spottiswoode ◽  
Amanda R. Ridley
Keyword(s):  
Climate Change ◽  
Group Size ◽  
Climatic Conditions ◽  
Breeding Bird ◽  
Body Mass Change ◽  
Species Vulnerability ◽  
Animal Populations ◽  
Cooperatively Breeding ◽  
Dry Conditions ◽  
The Impact

AbstractIncreasingly harsh and unpredictable climate regimes are affecting animal populations around the world as climate change advances. One relatively unexplored aspect of species vulnerability to climate change is whether and to what extent responses to environmental stressors might be mitigated by variation in group size in social species. We used a 15-year dataset for a cooperatively-breeding bird, the southern pied babbler Turdoides bicolor, to determine the impact of temperature, rainfall, and group size on body mass change and interannual survival in both juveniles and adults. Hot and dry conditions were associated with reduced juvenile growth, mass loss in adults, and compromised survival between years in both juveniles (−86%) and adults (−60%). Individuals across all group sizes experienced similar effects of climatic conditions. Larger group sizes may not buffer individual group members against the impacts of hot and dry conditions, which are expected to increase in frequency and severity in future.

scholarly journals Variable fledging age according to group size: trade-offs in a cooperatively breeding bird

2007 ◽  
Vol 3 (6) ◽  
pp. 624-627 ◽  
Author(s):  
N.J Raihani ◽  
A.R Ridley
Keyword(s):  
Group Size ◽  
Group Living ◽  
Breeding Bird ◽  
Communal Roost ◽  
Trade Offs ◽  
Efficient Detection ◽  
Risk Of Predation ◽  
Cooperatively Breeding ◽  
Individual Survival ◽  
Dilution Effects

Group living can provide individuals with several benefits, including cooperative vigilance and lower predation rates. Individuals in larger groups may be less vulnerable to predation due to dilution effects, efficient detection or greater ability to repel predators. Individuals in smaller groups may consequently employ alternative behavioural tactics to compensate for their greater vulnerability to predators. Here, we describe how pied babbler ( Turdoides bicolor ) fledging age varies with group size and the associated risk of nestling predation. Nestling predation is highest in smaller groups, but there is no effect of group size on fledgling predation. Consequently, small groups fledge young earlier, thereby reducing the risk of predation. However, there is a cost to this behaviour as younger fledglings are less mobile than older fledglings: they move shorter distances and are less likely to successfully reach the communal roost tree. The optimal age to fledge young appears to depend on the trade-off between reduced nestling predation and increased fledgling mobility. We suggest that such trade-offs may be common in species where group size critically affects individual survival and reproductive success.

How do population density and food supply influence social behaviour in the snowshoe hare (Lepus americanus)?

1993 ◽  
Vol 71 (6) ◽  
pp. 1084-1089 ◽  
Author(s):  
Jean Ferron
Keyword(s):  
Population Density ◽  
Breeding Season ◽  
Group Size ◽  
Food Availability ◽  
Social Behaviour ◽  
Lepus Americanus ◽  
Snowshoe Hare ◽  
Agonistic Behaviour ◽  
Nonbreeding Season ◽  
The Impact

The influence of population density and food on the social behaviour of the snowshoe hare (Lepus americanus) was studied in an outdoor enclosure. The year was divided into two periods: the nonbreeding season (October to March) and the breeding season (April to August). During each period, data on social interactions were recorded for groups of 4, 6, 8, and 10 animals, with three different sets of animals for each group size. Agonistic behaviour characterized social encounters between hares year-round. During the nonbreeding season, there was a significant correlation between agonistic behaviour and group size for females only. During the breeding season, the rate of interaction was lower and agonistic behaviour was significantly and negatively correlated with group size for males only. Two-way ANOVA of total agonistic behaviour revealed that group size and sex interacted significantly only during the nonbreeding season. The different categories of agonistic behaviour (aggression, threat, and taking the place of another animal) were also analysed separately. The distribution of aggression within each of the experimental groups indicated that the two top-ranking animals were generally males and that they initiated most of the aggressive encounters. Another experiment with restricted food availability was conducted to study the impact of limited resources on agonistic behaviour. Hares were significantly more aggressive when food was restricted than when food was available ad libitum. It thus appears that food availability has a stronger influence on social behaviour than does hare density.

scholarly journals Carbon Dynamics in the Northeastern Qinghai–Tibetan Plateau from 1990 to 2030 Using Landsat Land Use/Cover Change Data

2020 ◽  
Vol 12 (3) ◽  
pp. 528 ◽  
Author(s):  
Jingye Li ◽  
Jian Gong ◽  
Jean-Michel Guldmann ◽  
Shicheng Li ◽  
Jie Zhu
Keyword(s):  
Land Use ◽  
Tibetan Plateau ◽  
Carbon Storage ◽  
Sharp Decrease ◽  
Total Carbon ◽  
Qinghai Lake ◽  
Lake Basin ◽  
Ecosystem Carbon ◽  
Trade Offs ◽  
The Impact

Land use/cover change (LUCC) has an important impact on the terrestrial carbon cycle. The spatial distribution of regional carbon reserves can provide the scientific basis for the management of ecosystem carbon storage and the formulation of ecological and environmental policies. This paper proposes a method combining the CA-based FLUS model and the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model to assess the temporal and spatial changes in ecosystem carbon storage due to land-use changes over 1990–2015 in the Qinghai Lake Basin (QLB). Furthermore, future ecosystem carbon storage is simulated and evaluated over 2020–2030 under three scenarios of natural growth (NG), cropland protection (CP), and ecological protection (EP). The long-term spatial variations in carbon storage in the QLB are discussed. The results show that: (1) Carbon storage in the QLB decreased at first (1990–2000) and increased later (2000–2010), with total carbon storage increasing by 1.60 Tg C (Teragram: a unit of mass equal to 1012 g). From 2010 to 2015, carbon storage displayed a downward trend, with a sharp decrease in wetlands and croplands as the main cause; (2) Under the NG scenario, carbon reserves decrease by 0.69 Tg C over 2020–2030. These reserves increase significantly by 6.77 Tg C and 7.54 Tg C under the CP and EP scenarios, respectively, thus promoting the benign development of the regional ecological environment. This study improves our understanding on the impact of land-use change on carbon storage for the QLB in the northeastern Qinghai–Tibetan Plateau (QTP).

scholarly journals Discrete choice experiment for eliciting preference for health services for patients with ALS and their informal caregivers

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Katy Tobin ◽  
Sinead Maguire ◽  
Bernie Corr ◽  
Charles Normand ◽  
Orla Hardiman ◽  
...  
Keyword(s):  
Health Services ◽  
Discrete Choice Experiment ◽  
Discrete Choice ◽  
Choice Experiment ◽  
Strong Preference ◽  
Multidisciplinary Teams ◽  
Relative Importance ◽  
Trade Offs ◽  
Als Patients ◽  
The Impact

Abstract Background Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative condition with a mean life expectancy of 3 years from first symptom. Understanding the factors that are important to both patients and their caregivers has the potential to enhance service delivery and engagement, and improve efficiency. The Discrete Choice Experiment (DCE) is a stated preferences method which asks service users to make trade-offs for various attributes of health services. This method is used to quantify preferences and shows the relative importance of the attributes in the experiment, to the service user. Methods A DCE with nine choice sets was developed to measure the preferences for health services of ALS patients and their caregivers and the relative importance of various aspects of care, such as timing of care, availability of services, and decision making. The DCE was presented to patients with ALS, and their caregivers, recruited from a national multidisciplinary clinic. A random effects probit model was applied to estimate the impact of each attribute on a participant’s choice. Results Patients demonstrated the strongest preferences about timing of receiving information about ALS. A strong preference was also placed on seeing the hospice care team later rather than early on in the illness. Patients also indicated their willingness to consider the use of communication devices. Grouping by stage of disease, patients who were in earlier stages of disease showed a strong preference for receipt of extensive information about ALS at the time of diagnosis. Caregivers showed a strong preference for engagement with healthcare professionals, an attribute that was not prioritised by patients. Conclusions The DCE method can be useful in uncovering priorities of patients and caregivers with ALS. Patients and caregivers have different priorities relating to health services and the provision of care in ALS, and patient preferences differ based on the stage and duration of their illness. Multidisciplinary teams must calibrate the delivery of care in the context of the differing expectations, needs and priorities of the patient/caregiver dyad.

scholarly journals Modeling Energy Communities with Collective Photovoltaic Self-Consumption: Synergies between a Small City and a Winery in Portugal

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 323
Author(s):  
Guilherme Pontes Luz ◽  
Rodrigo Amaro e Silva
Keyword(s):  
Economic Feasibility ◽  
Small City ◽  
Total System ◽  
Trade Offs ◽  
Southern Portugal ◽  
Energy Community ◽  
Individual Self ◽  
The Impact ◽  
The City ◽  
Modest Reduction

The recently approved regulation on Energy Communities in Europe is paving the way for new collective forms of energy consumption and production, mainly based on photovoltaics. However, energy modeling approaches that can adequately evaluate the impact of these new regulations on energy community configurations are still lacking, particularly with regards to the grid tariffs imposed on collective systems. Thus, the present work models three different energy community configurations sustained on collective photovoltaics self-consumption for a small city in southern Portugal. This energy community, which integrates the city consumers and a local winery, was modeled using the Python-based Calliope framework. Using real electricity demand data from power transformers and an actual winery, the techno-economic feasibility of each configuration was assessed. Results show that all collective arrangements can promote a higher penetration of photovoltaic capacity (up to 23%) and a modest reduction in the overall cost of electricity (up to 8%). However, there are clear trade-offs between the different pathways: more centralized configurations have 53% lower installation costs but are more sensitive to grid use costs (which can represent up to 74% of the total system costs). Moreover, key actor’s individual self-consumption rate may decrease by 10% in order to benefit the energy community as a whole.

scholarly journals Using Satellite Data for CBRN (Chemical, Biological, Radiological, and Nuclear) Threat Detection, Monitoring, and Modelling

2021 ◽  
Author(s):  
Gary Sutlieff ◽  
Lucy Berthoud ◽  
Mark Stinchcombe
Keyword(s):  
Satellite Data ◽  
Meteorological Data ◽  
Atmospheric Composition ◽  
Chemical Detection ◽  
List Type ◽  
Data Types ◽  
Wide Range ◽  
Future Technologies ◽  
The Impact ◽  
Near Future

Abstract CBRN (Chemical, Biological, Radiological, and Nuclear) threats are becoming more prevalent, as more entities gain access to modern weapons and industrial technologies and chemicals. This has produced a need for improvements to modelling, detection, and monitoring of these events. While there are currently no dedicated satellites for CBRN purposes, there are a wide range of possibilities for satellite data to contribute to this field, from atmospheric composition and chemical detection to cloud cover, land mapping, and surface property measurements. This study looks at currently available satellite data, including meteorological data such as wind and cloud profiles, surface properties like temperature and humidity, chemical detection, and sounding. Results of this survey revealed several gaps in the available data, particularly concerning biological and radiological detection. The results also suggest that publicly available satellite data largely does not meet the requirements of spatial resolution, coverage, and latency that CBRN detection requires, outside of providing terrain use and building height data for constructing models. Lastly, the study evaluates upcoming instruments, platforms, and satellite technologies to gauge the impact these developments will have in the near future. Improvements in spatial and temporal resolution as well as latency are already becoming possible, and new instruments will fill in the gaps in detection by imaging a wider range of chemicals and other agents and by collecting new data types. This study shows that with developments coming within the next decade, satellites should begin to provide valuable augmentations to CBRN event detection and monitoring. Article Highlights There is a wide range of existing satellite data in fields that are of interest to CBRN detection and monitoring. The data is mostly of insufficient quality (resolution or latency) for the demanding requirements of CBRN modelling for incident control. Future technologies and platforms will improve resolution and latency, making satellite data more viable in the CBRN management field

scholarly journals Does agricultural intensification cause tipping points in ecosystem services?

2021 ◽  
Author(s):  
Stephen C. L. Watson ◽  
Adrian C. Newton ◽  
Lucy E. Ridding ◽  
Paul M. Evans ◽  
Steven Brand ◽  
...  
Keyword(s):  
Ecosystem Services ◽  
Agricultural Intensification ◽  
Spatial Dynamics ◽  
Policy Option ◽  
List Type ◽  
Tipping Points ◽  
Software Models ◽  
Non Linear ◽  
Study Interval ◽  
The Impact

Abstract Context Agricultural intensification is being widely pursued as a policy option to improve food security and human development. Yet, there is a need to understand the impact of agricultural intensification on the provision of multiple ecosystem services, and to evaluate the possible occurrence of tipping points. Objectives To quantify and assess the long-term spatial dynamics of ecosystem service (ES) provision in a landscape undergoing agricultural intensification at four time points 1930, 1950, 1980 and 2015. Determine if thresholds or tipping points in ES provision may have occurred and if there are any detectable impacts on economic development and employment. Methods We used the InVEST suite of software models together with a time series of historical land cover maps and an Input–Output model to evaluate these dynamics over an 85-year period in the county of Dorset, southern England. Results Results indicated that trends in ES were often non-linear, highlighting the potential for abrupt changes in ES provision to occur in response to slight changes in underlying drivers. Despite the fluctuations in provision of different ES, overall economic activity increased almost linearly during the study interval, in line with the increase in agricultural productivity. Conclusions Such non-linear thresholds in ES will need to be avoided in the future by approaches aiming to deliver sustainable agricultural intensification. A number of positive feedback mechanisms are identified that suggest these thresholds could be considered as tipping points. However, further research into these feedbacks is required to fully determine the occurrence of tipping points in agricultural systems.

128 Development of an M1-polarized, non-viral chimeric antigen receptor macrophage (CAR-M) platform for cancer immunotherapy

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A141-A141
Author(s):  
Yumi Ohtani ◽  
Kayleigh Ross ◽  
Aditya Dandekar ◽  
Rashid Gabbasov ◽  
Michael Klichinsky
Keyword(s):  
Cancer Immunotherapy ◽  
Chimeric Antigen Receptor ◽  
Scale Up ◽  
Antigen Receptor ◽  
Innate Immune ◽  
List Type ◽  
M1 Phenotype ◽  
The Impact ◽  
Anti Tumor Activity ◽  
Immunosuppressive Factors

BackgroundWe have previously developed CAR-M as a novel cell therapy approach for the treatment of solid tumors.1 CAR-M have the potential to overcome key challenges that cell therapies face in the solid tumor setting – tumor infiltration, immunosuppression, lymphocyte exclusion – and can induce epitope spreading to overcome target antigen heterogeneity. While macrophages transduced with the adenoviral vector Ad5f35 (Ad CAR-M) traffic to tumors, provide robust anti-tumor activity, and recruit and activate T cells, we sought to identify a robust non-viral method of macrophage engineering in order to reduce the cost of goods, manufacturing complexity, and potential immunogenicity associated with viral vectors.MethodsAs innate immune cells, macrophages detect exogenous nucleic acids and respond with inflammatory and apoptotic programs. Thus, we sought to identify a means of mRNA delivery that avoids recognition by innate immune sensors. We screened a broad panel of mRNA encoding an anti-HER2 CAR comprising multiplexed 5’Cap and base modifications using an optimized and scalable electroporation approach and evaluated the impact of interferon-β priming on CAR-M phenotype and function.ResultsWe identified the optimal multiplexed mRNA modifications that led to maximal macrophage viability, transfection efficiency, intensity of CAR expression, and duration of expression. Non-viral HER2 CAR-M phagocytosed and killed human HER2+ tumor cells. Unlike Ad CAR-M, mRNA CAR-M were not skewed toward an M1 state by mRNA electroporation. Priming non-viral CAR-M with IFN-β induced a durable M1 phenotype, as shown by stable upregulation of numerous M1 markers and pathways. IFN-β priming significantly enhanced the anti-tumor activity of CAR but not control macrophages. IFN-β primed mRNA CAR-M were resistant to M2 conversion, maintaining an M1 phenotype despite challenge with various immunosuppressive factors, and converted bystander M2 macrophages toward M1. Interestingly, priming mRNA CAR-M with IFN-β significantly enhanced the persistence of CAR expression, overcoming the known issue of rapid mRNA turnover. RNA-seq analysis revealed that IFN-β priming affected pathways involved in increasing translation and decreasing RNA degradation in human macrophages.ConclusionsWe have established a novel, optimized non-viral CAR-M platform based on chemically modified mRNA and IFN-β priming. IFN-β priming induced a durable M1 phenotype, improved CAR expression, improved CAR persistence, led to enhanced anti-tumor function, and rendered resistance to immunosuppressive factors. This novel platform is amenable to scale-up, GMP manufacturing, and represents an advance in the development of CAR-M.ReferenceKlichinsky M, Ruella M, Shestova O, et al. Human chimeric antigen receptor macrophages for cancer immunotherapy. Nat Biotechnol 2020;38(8):947–953.

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