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Doran, C.

Publications and source records attributed to Doran, C..

3 recordsLinked to original sources

Group-level phenotypes are idiosyncratic yet unpredictable over development in a clonal fish

Behavioral differences among groups can have profound impacts on individual fitness, yet how group-level phenotypes arise and change during development is poorly understood. Group-level differences may originate from genetic differences or subtle variation among individuals, but they can also emerge over time through social feedback mechanisms within and between groups, potentially producing dramatically different group-level behavior. Disentangling these drivers of group phenotypes is challenging because groups are typically studied after they are already well established. Using the naturally clonal Amazon molly, we establish replicate groups of genetically identical individuals and continuously track group-level behavior from birth throughout the first 55 days of life. This design allows us to control for genetic and environmental sources of variance, thereby establishing a null baseline for group-level differences. Furthermore, by recording over an extended period beginning from day 1 of life, we test whether group phenotypes follow predictable trajectories driven by individual differences or instead diverge due to social feedback during development. We find that average behavioral changes across groups follow predictable patterns during this early developmental phase. In contrast, differences among groups are highly unstable over longer timescales: although groups differ from very early in life, it appears that the rank-order of group-level phenotypes undergoes a shuffling mid-development, around 4-5 weeks of age. These results suggest that distinct processes generate group-level variation across ontogeny, with early differences largely reflecting consistent individual variation; then as individuals mature and become more socially responsive, social feedbacks push groups along divergent, less predictable behavioral trajectories.

animal behavior and cognition↗

The effectiveness and cost effectiveness of a hospital avoidance program in a residential aged care facility

BackgroundResidential aged care facility residents experience high rates of hospital admissions which are stressful, costly and often preventable.\n\nDesignProspective pre-post cohort study and decision model analysis\n\nInterventionA decision-support tool was implemented to enable nursing staff to detect, refer and quickly respond to early signals of a deteriorating resident. Advanced clinical skills training, new diagnostic equipment and guided support from clinical lead nurses and nurse practitioners was provided to support nursing staff in the delivery of appropriate sub-acute care.\n\nOutcome measuresRate of hospital admissions; length of stay; incremental cost per QALY; net monetary benefit.\n\nResultsThe hospital avoidance program was associated with a 19% reduction in annual hospital admissions and a 31% reduction in the average length of stay. When modelled in a cohort of 1,000 residents the program resulted in a total of 1,606 fewer hospital bed days per annum. This contributed to a total cost saving of $2.6 million and 0.62 incremental QALYs gained per 1,000 residents. The program had a positive net monetary benefit and was considered cost-effective, even when the willingness to pay for health care gains was set to zero. A probabilistic sensitivity analysis estimated that there was an 86% probability that the program was cost-effective after taking the uncertainty of the model inputs into account.\n\nConclusionsThis study provides compelling evidence for the effectiveness and cost-effectiveness of a RACF nurse led sub-acute care program in preventing unnecessary hospital admissions.

epidemiology↗

Familiarity increases aggressiveness among clonal fish.

Understanding how animal groups form and function is a major goal in behavioural ecology. Both genetic relatedness and familiarity among group mates have been shown to be key mediators of group composition. However, disentangling the two in most species is challenging as the most familiar individuals are often the most related, and vice versa. In order to gain a complete understanding of how individual interactions shape group behaviour it is crucial to understand the role each of this social relationship factors plays individually. To this end, we manipulated the level of familiarity among groups of the naturally clonal, and genetically identical fish, the Amazon molly (Poecilia formosa) and monitored group behaviour in an open-field and when given the opportunity to forage. Contrary to our predictions, fish that were the most familiar with each other showed the highest levels of aggression. Additionally, fish that were less familiar with each other exhibited the highest group cohesion and took the longest to begin feeding, compared to the more familiar fish. These results suggest that familiarity may socially buffer individuals from the perception of risk in novel environments, such as is common in most behavioural tests designed to test group behaviour. Increases in aggression that are associated with increasing familiarity as shown here might be a mechanism by which fish maintain a fission-fusion society with important consequences for the patterns of associations in group living animals.

animal behavior and cognition↗