1,314 research outputs found

    Not statistically significant, but still scientific

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    Birch’s formulation is persuasive but not nuanced enough to capture at least one situation where it is reasonable to invoke the precautionary principle (PP): when we have multiple, weak, but convergent, lines of evidence that a species is sentient, but no statistically significant evidence of a single credible indicator of sentience within the order as required by BAR. I respond to the worry that if we include such cases in our framework for applying the PP, we open ourselves to the charge of being “unscientific.

    Rethinking Behavioural Evolution

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    Proximate Versus Ultimate Causation and Evo-Devo

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    Made famous by Ernst Mayr (1961), the distinction between proximate and ultimate causation in biological explanation is widely seen as a key tenet of evolutionary theory and a central organizing principle for evolutionary research. The study of immediate, individual-level mechanistic causes of development or physiology (“proximate causation”) is distinguished from the study of historical, population-level statistical causes in evolutionary biology (“ultimate causation”). Since evolutionary developmental biology (evo-devo) is a field that explicitly uses so-called “proximate” sciences such as developmental biology, morphology, and embryology in the study of evolution, it challenges the standard construal of the proximate- ultimate distinction and its associated account of causation. The exact nature of the challenge and its ramifications for the viability of the distinction more broadly are contested, but these conceptual questions are central to the status and significance of evo-devo in contemporary evolutionary biology

    Is cultural evolution always fast? Challenging the idea that cognitive gadgets would be capable of rapid and adaptive evolution

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    Against the background of “arms race” style competitive explanations for complex human cognition, such as the Social Intelligence Hypothesis (Byrne & Whiten, 1988; Humphrey, 1976; Jolly, 1966), and theories that tie complex cognition with environmental variability more broadly (Godfrey-Smith, 1996, 2001), the idea that culturally inherited mechanisms for social cognition would be more capable of responding to the labile social environment is a compelling one. Whilst it is tempting to think that the evolvability of culturally inherited cognitive mechanisms such as Cecilia Heyes’ (2018) cognitive gadgets would be akin to culturally inherited tools like axes or canoes (i.e., relatively easy to modify to adaptive benefit, and relatively robustly inherited), I draw on established theory in evolutionary developmental biology to show that this is a mistake. Their causal translucency, along with the degree to which they would be integrated within the organism, make cognitive gadgets far more like genetically inherited traits with respect to their evolvability. Consequently, their evolution is unlikely to be particularly fast or nimble. In making clear the constraints on the evolution of culturally inherited cognition and how they must influence our theorising, the discussion also highlights the value of thinking about evolvability in this domain

    Structuralism and Selectionism: Friends or Foes?

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    Historically, the empirical study of phenotypic diversification has fallen into two rough camps; (1) "structuralist approaches" focusing on developmental constraint, bias and innovation (with evo-devo at the core); and (2) "adaptationist approaches" focusing on adaptation and natural selection. Whilst debates, such as that surrounding the proposed "Extended" Evolutionary Synthesis, often juxtapose these two positions, this review focuses on the grey space in between. Specifically, here I look at the motivations behind the "structuralist" and "adaptationist" positions in order to make clear the ways that these two approaches to understanding phenotypic variation are in conflict, along with the ways in which they are commensurable. In doing so, this review makes much clearer (a) the particular value of the evo-devo approach to phenotypic diversity, but also (b) how it properly relates to other predominant approaches to the same issues in evolutionary biology more broadly

    Mapping Out the Landscape: A Multi-dimensional Approach to Behavioural Innovation

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    Transformations in the “behavioural innovativeness” of species—broadly, the capacity to generate new or novel behaviours—are often associated with significant evolutionary shifts in cognition. Whilst this assumption is intuitively and theoretically appealing, it lacks strong empirical support. One barrier to such support is the lack of a good measure of behavioural innovation. This paper offers a solution to this problem by breaking down innovation into its components and presenting a novel multi-dimensional framework for characterising and comparing putative cases of behavioural innovation

    Smartphones: Parts of Our Minds? Or Parasites?

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    The smartphone is often assumed to be an obvious example of cognitive extension. We offer reasons to reject this assessment, arguing that modern smartphones (and the apps installed on them) are not cognitive extensions after all. Modern smartphones are designed to manipulate the attention and behaviour of users in ways that further the interests of the corporations that built them. In this they are importantly different from resources typically associated with the extended mind—such as notebooks, Scrabble racks and maps—which are not designed to manipulate or exploit users (even if they can be corrupted to these ends in some cases). It is not plausible for a part of the cognitive system to be designed to thwart the goals and desires of the user in the way a modern smartphone is. Given this, we argue, modern smartphones are better understood as external to, but symbiotic with, our minds, and, sometimes even parasitic on us, rather than as cognitive extensions. Thinking about them in this way better reflects the true nature of our relationship with them, and the ways that the relationship can both benefit and harm us

    Corn Residue Use by Livestock in the United States

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    Corn (Zea mays L.) residue grazing or harvest provides a simple and economical practice to integrate crops and livestock, but limited information is available on how widespread corn residue utilization is practiced by US producers. In 2010, the USDA Economic Research Service surveyed producers from 19 states on corn grain and residue management practices. Total corn residue grazed or harvested was 4.87 million ha. Approximately 4.06 million ha was grazed by 11.7 million livestock (primarily cattle) in 2010. The majority of grazed corn residue occurred in Nebraska (1.91 million ha), Iowa (385,000 ha), South Dakota (361,000 ha), and Kansas (344,000 ha). Average grazing days ranged from 10 to 73 d (mean = 40 d). Corn residue harvests predominantly occurred in the central and northern Corn Belt, with an estimated 2.9 Tg of corn residue harvested across the 19 states. This survey highlights the importance of corn residue for US livestock, particularly in the western Corn Belt

    Comparing alternating pressure mattresses and high-specification foam mattresses to prevent pressure ulcers in high-risk patients: the PRESSURE 2 RCT

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    Background: Pressure ulcers (PUs) are a burden to patients, carers and health-care providers. Specialist mattresses minimise the intensity and duration of pressure on vulnerable skin sites in at-risk patients. Primary objective: Time to developing a new PU of category ≥ 2 in patients using an alternating pressure mattress (APM) compared with a high-specification foam mattress (HSFM). Design: A multicentre, Phase III, open, prospective, planned as an adaptive double-triangular group sequential, parallel-group, randomised controlled trial with an a priori sample size of 2954 participants. Randomisation used minimisation (incorporating a random element). Setting: The trial was set in 42 secondary and community inpatient facilities in the UK. Participants: Adult inpatients with evidence of acute illness and at a high risk of PU development. Interventions and follow-up: APM or HSFM – the treatment phase lasted a maximum of 60 days; the final 30 days were post-treatment follow-up. Main outcome measures: Time to event. Results: From August 2013 to November 2016, 2029 participants were randomised to receive either APM (n = 1016) or HSFM (n = 1013). Primary end point – 30-day final follow-up: of the 2029 participants in the intention-to-treat population, 160 (7.9%) developed a new PU of category ≥ 2. There was insufficient evidence of a difference between groups for time to new PU of category ≥ 2 [Fine and Gray model HR 0.76, 95% confidence interval (CI) 0.56 to 1.04; exact p-value of 0.0890 and 2% absolute difference]. Treatment phase sensitivity analysis: 132 (6.5%) participants developed a new PU of category ≥ 2 between randomisation and end of treatment phase. There was a statistically significant difference in the treatment phase time-to-event sensitivity analysis (Fine and Gray model HR 0.66, 95% CI 0.46 to 0.93; p = 0.0176 and 2.6% absolute difference). Secondary end points – 30-day final follow-up: new PUs of category ≥ 1 developed in 350 (17.2%) participants, with no evidence of a difference between mattress groups in time to PU development, (Fine and Gray model HR 0.83, 95% CI 0.67 to 1.02; p-value = 0.0733 and absolute difference 3.1%). New PUs of category ≥ 3 developed in 32 (1.6%) participants with insufficient evidence of a difference between mattress groups in time to PU development (Fine and Gray model HR 0.81, 95% CI 0.40 to 1.62; p = 0.5530 and absolute difference 0.4%). Of the 145 pre-existing PUs of category 2, 89 (61.4%) healed – there was insufficient evidence of a difference in time to healing (Fine and Gray model HR 1.12, 95% CI 0.74 to 1.68; p = 0.6122 and absolute difference 2.9%). Health economics – the within-trial and long-term analysis showed APM to be cost-effective compared with HSFM; however, the difference in costs models are small and the quality-adjusted life-year gains are very small. There were no safety concerns. Blinded photography substudy – the reliability of central blinded review compared with clinical assessment for PUs of category ≥ 2 was ‘very good’ (kappa statistic 0.82, prevalence- and bias-adjusted kappa 0.82). Quality-of-life substudy – the Pressure Ulcer Quality of Life – Prevention (PU-QoL-P) instrument meets the established criteria for reliability, construct validity and responsiveness. Limitations: A lower than anticipated event rate. Conclusions: In acutely ill inpatients who are bedfast/chairfast and/or have a category 1 PU and/or localised skin pain, APMs confer a small treatment phase benefit that is diminished over time. Overall, the APM patient compliance, very low PU incidence rate observed and small differences between mattresses indicate the need for improved indicators for targeting of APMs and individualised decision-making. Decisions should take into account skin status, patient preferences (movement ability and rehabilitation needs) and the presence of factors that may be potentially modifiable through APM allocation, including being completely immobile, having nutritional deficits, lacking capacity and/or having altered skin/category 1 PU. Future work: Explore the relationship between mental capacity, levels of independent movement, repositioning and PU development. Explore ‘what works for whom and in what circumstances’. Trial registration: Current Controlled Trials ISRCTN01151335. Funding: This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 52. See the NIHR Journals Library website for further project information
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