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At the end of the 19th century, the suggestion was made by several scientists, including J. M. Baldwin, that behavioral responses to environmental change could both rescue populations from extinction (Baldwin Effect) and influence the course of subsequent evolution. Here we provide the historical and theoretical background for this argument and offer evidence of the importance of these ideas for understanding how animals (and other organisms that exhibit behavior) will respond to the rapid environmental changes caused by human activity. We offer examples from long-term research on the evolution of behavioral and other phenotypes in the adaptive radiation of the threespine stickleback fish (Gasterosteus aculeatus), a radiation in which it is possible to infer ancestral patterns of behavioral plasticity relative to the post-glacial freshwater radiation in northwestern North America, and to use patterns of parallelism and contemporary evolution to understand adaptive causes of responses to environmental modification. Our work offers insights into the complexity of cognitive responses to environmental change, and into the importance of examining multiple aspects of the phenotype simultaneously, if we are to understand how behavioral shifts contribute to the persistence of populations and to subsequent evolution. We conclude by discussing the origins of apparent novelties induced by environmental shifts, and the importance of accounting for geographic variation within species if we are to accurately anticipate the effects of anthropogenic environmental modification on the persistence and evolution of animals. [ABSTRACT FROM AUTHOR]

Invasive predators often impose devastating selection pressures on native prey species. However, their effects can be regionally dependent and influenced by the local ecological conditions of their invaded habitats. Evolved behavioral phenotypes are important mechanisms by which prey adapt to the presence of novel predators. Here, we asked how behavior and behavioral plasticity of threespine stickleback (Gasterosteus aculeatus) populations have evolved following the introduction of the invasive predator, northern pike (Esox lucius). We examined the behavior of F1 offspring generated from three pike-free and three pike-invaded populations and measured how stickleback activity and plant use behaviors, and their plasticity, have evolved following pike introduction. To evaluate plasticity, we exposed juvenile stickleback to predator cues during their first year of development and then evaluated how this repeated exposure influenced behavioral responses to an artificial predation event. We found no overarching effect of pike in either evolved behaviors or behavioral plasticity, and no evidence for the presence of developmental plasticity. Furthermore, we found that depending on the phenotype, pike-invaded stickleback populations have either more or less among-population variation than pike-free populations. Our results suggest that evolution in response to invasive predators may be hidden by local adaptation when enough populations are studied. [ABSTRACT FROM AUTHOR]

Introduction: long-term care (LTC) residents have higher hospitalisation rates than non-LTC residents. Rapid decline may follow hospitalisations, hence the importance of preventing unnecessary hospitalisations. Literature describes diagnosis-specific interventions (for cardiac failure, ischaemic heart disease, chronic obstructive pulmonary disease, stroke, pneumonia--termed 'big five' diagnoses), impacting on hospitalisations of older community-dwellers, but few RCTs show reductions in acute admissions from LTC. Methods: LTC facilities with higher than expected hospitalisations were recruited for a cluster-randomised controlled trial (RCT) of facility-based complex, non-disease-specific, 9-month intervention comprising gerontology nurse specialist (GNS)-led staff education, facility benchmarking, GNS resident review and multidisciplinary discussion of residents selected using standard criteria. In this post hoc exploratory analysis, the outcome was acute hospitalisations for 'big five' diagnoses. Re-randomisation analyses were used for end points during months 1-14. For end points during months 4-14, proportional hazards models are adjusted for within-facility clustering. Results: we recruited 36 facilities with 1,998 residents (1,408 female; mean age 82.9 years); 1,924 were alive at 3 months. The intervention did not impact overall rates of acute hospitalisations or mortality (previously published), but resulted in fewer 'big five' admissions (RR = 0.73, 95% CI = 0.54-0.99; P = 0.043) with no significant difference in the rate of other acute admissions. When considering events occurring after 3 months (only), the intervention group were 34.7% (HR = 0.65; 95% CI = 0.49-0.88; P=0.005) less likely to have a 'big five' acute admission than controls, with no differences in likelihood of acute admissions for other diagnoses (P = 0.96). Conclusions: this generic intervention may reduce admissions for common conditions which the literature shows are impacted by disease-specific admission reduction strategies. [ABSTRACT FROM AUTHOR]

Background: in Auckland, New Zealand in 1988, 7.7% of those aged over 65 years lived in licenced residential aged care. Age-specific rates approximately doubled for each 5-year age group after the age of 65 years. Even with changes in policies and market forces since 1988, population increases are forecast to drive large growth in demand. This study shows previously unrecognised 20-year trends in rates of care in a geographically defined population.Methods: four cross-sectional surveys of all facilities (rest homes and hospitals) licenced for long-term care of older people were conducted in Auckland, New Zealand in 1988, 1993, 1998 and 2008. Facility staff completed survey forms for each resident. Numbers of licenced and occupied beds and trends in age-specific and age-standardised rates in residential aged care are reported.Results: over the 20-year period, Auckland's population aged over 65 years increased by 43% (from 91,000 to 130,000) but actual numbers in care reduced slightly. Among those aged over 65 years, the proportion living in care facilities reduced from 1 in 13 to 1 in 18. Age-standardised rates in rest-home level care reduced from 65 to 33 per thousand, and in hospital level care, from 29 to 23 per thousand. Had rates remained stable, over 13,200 people, 74% more than observed, would have been in care in 2008.Conclusion: growth predicted in the residential aged care sector is not yet evident. The introduction of standardised needs assessments before entry, increased availability of home-based services, and growth in retirement villages may have led to reduced utilisation. [ABSTRACT FROM PUBLISHER]

Background. Organisms resistant to antimicrobials continue to emerge and spread. This study was performed to measure the medical and societal cost attributable to antimicrobial-resistant infection (ARI). Methods. A sample of high-risk hospitalized adult patients was selected. Measurements included ARI, total cost, duration of stay, comorbidities, acute pathophysiology, Acute Physiology and Chronic Health Evaluation III score, intensive care unit stay, surgery, health care-acquired infection, and mortality. Hospital services used and outcomes were abstracted from electronic and written medical records. Medical costs were measured from the hospital perspective. A sensitivity analysis including 3 study designs was conducted. Regression was used to adjust for potential confounding in the random sample and in the sample expanded with additional patients with ARI. Propensity scores were used to select matched control subjects for each patient with ARI for a comparison of mean cost for patients with and without ARI. Results. In a sample of 1391 patients, 188 (13.5%) had ARI. The medical costs attributable to ARI ranged from $18,588 to $29,069 per patient in the sensitivity analysis. Excess duration of hospital stay was 6.4-12.7 days, and attributable mortality was 6.5%. The societal costs were $10.7-$15.0 million. Using the lowest estimates from the sensitivity analysis resulted in a total cost of $13.35 million in 2008 dollars in this patient cohort. Conclusions. The attributable medical and societal costs of ARI are considerable. Data from this analysis could form the basis for a more comprehensive evaluation of the cost of resistance and the potential economic benefits of prevention programs. [ABSTRACT FROM AUTHOR]