This chapter offers an essay on the evolution of evolvability. It investigates the most frequently cited arguments against the possibility that the evolution of evolvability might be the result of selection favoring more evolvable genotypes. The chapter argues that all these arguments have not been rigorously analyzed by their proponents, and are thus a self-inflicted blind spot in evolutionary biology, and indicates that there are no deep conceptual obstacles for population genetic theory to explain the evolution of evolvability. The very (...) focus on this subject will help shift the perspective of evolutionary biology toward a more holistic, systemic view of evolution. (shrink)

The problem of modifier evolution was examined with regard to the idea that modifier evolution can be considered as a result of selection for adaptation speed in populations far from equilibrium. This kind of selection was called feedback selection in order to emphasize the difference to theories which consider modifier evolution near the equilibrium. The basic principles of this kind of selection are derived for asexual populations and the problem of dominance is discussed in the light of this concept. In (...) general the results support the view, that the genetic properties of a character are selected along with the character itself. (shrink)

It is widely accepted that stressful conditions can facilitate evolutionary change. The mechanisms elucidated thus far accomplish this with a generic increase in heritable variation that facilitates more rapid adaptive evolution, often via plastic modifications of existing characters. Through scrutiny of different meanings of stress in biological research, and an explicit recognition that stressors must be characterized relative to their effect on capacities for maintaining functional integrity, we distinguish between: (1) previously identified stress-responsive mechanisms that facilitate evolution by maintaining an (...) adaptive fit with the environment, and (2) the co-option of stress-responsive mechanisms that are specific to stressors leading to the origin of novelties via compensation. Unlike standard accounts of gene co-option that identify component sources of evolutionary change, our model documents the cost-benefit trade-offs and thereby explains how one mechanism—an immediate response to acute stress—is transformed evolutionarily into another—routine protection from recurring stressors. We illustrate our argument with examples from cell type origination as well as processes and structures at higher levels of organization. These examples suggest a general principle of evolutionary origination based on the capacity to switch between regulatory states related to reproduction and proliferation versus survival and differentiation. (shrink)

A central topic in research at the intersection of development and evolution is the origin of novel traits. Despite progress on understanding how developmental mechanisms underlie patterns of diversity in the history of life, the problem of novelty continues to challenge researchers. Here we argue that research on evolutionary novelty and the closely associated phenomenon of co-option can be reframed fruitfully by: (1) specifying a conceptual model of mechanisms that underwrite character identity, (2) providing a richer and more empirically precise (...) notion of co-option that goes beyond common appeals to “deep homology”, and (3) attending to the nature of experimental interventions that can determine whether and how the co-option of identity mechanisms can help to explain novel character origins. This reframing has the potential to channel future investigation to make substantive progress on the problem of evolutionary novelty. To illustrate this potential, we apply our reframing to two case studies: treehopper helmets and beetle horns. (shrink)

Given the pervasiveness of gene sharing in evolution and the extent of homology across the tree of life, why is everything not homologous with everything else? The continuity and overlapping genetic contributions to diverse traits across lineages seem to imply that no discrete determination of homology is possible. Although some argue that the widespread overlap in parts and processes should be acknowledged as “partial” homology, this threatens a broad base of presumed comparative morphological knowledge accepted by most biologists. Following a (...) long scientific tradition, we advocate a strategy of “theoretical articulation” that introduces further distinctions to existing concepts to produce increased contrastive resolution among the labels used to represent biological phenomena. We pursue this strategy by drawing on successful patterns of reasoning from serial homology at the level of gene sequences to generate an enriched characterization of serial homology as a hierarchical, phylogenetic concept. Specifically, we propose that the concept of serial homology should be applied primarily to repeated but developmentally individualized body parts, such as cell types, differentiated body segments, or epidermal appendages. For these characters, a phylogenetic history can be reconstructed, similar to families of paralogous genes, endowing the notion of serial homology with a hierarchical, phylogenetic interpretation. On this basis, we propose a five-fold theoretical classification that permits a more fine-grained mapping of diverse trait-types. This facilitates answering the question of why everything is not homologous with everything else, as well as how novelty is possible given that any new character possesses evolutionary precursors. We illustrate the fecundity of our account by reference to debates over insect wing serial homologs and vertebrate paired appendages. (shrink)

Recently, Rueger and Sharp (1996) and Koperski (1998) have been concerned to show that certain procedural accounts of model confirmation are compromised by non-linear dynamics. We suggest that the issues raised are better approached by considering whether chaotic data analysis methods allow for reliable inference from data. We provide a framework and an example of this approach.

IntroductionTranscranial magnetic stimulation is a consolidated procedure for the treatment of depression, with several meta-analyses demonstrating its efficacy. Theta-burst stimulation is a modification of TMS with similar efficacy and shorter session duration. The geriatric population has many comorbidities and a high prevalence of depression, but few clinical trials are conducted specifically for this age group. TBS could be an option in this population, offering the advantages of few side effects and no pharmacological interactions. Therefore, our aim is to investigate the (...) efficacy of TBS in geriatric depression.Clinical trial registration[https://clinicaltrials.gov/ct2/], identifier [NCT04842929]. (shrink)

We establish a probabilized version of modus tollens, deriving from p(E|H)=a and p()=b the best possible bounds on p(). In particular, we show that p() 1 as a, b 1, and also as a, b 0. Introduction Probabilities of conditionals Conditional probabilities 3.1 Adams' thesis 3.2 Modus ponens for conditional probabilities 3.3 Modus tollens for conditional probabilities.

Evidentiary propositions E 1 and E 2, each p-positively relevant to some hypothesis H, are mutually corroborating if p > p, i = 1, 2. Failures of such mutual corroboration are instances of what may be called the corroboration paradox. This paper assesses two rather different analyses of the corroboration paradox due, respectively, to John Pollock and Jonathan Cohen. Pollock invokes a particular embodiment of the principle of insufficient reason to argue that instances of the corroboration paradox are of negligible (...) probability, and that it is therefore defeasibly reasonable to assume that items of evidence positively relevant to some hypothesis are mutually corroborating. Taking a different approach, Cohen seeks to identify supplementary conditions that are sufficient to ensure that such items of evidence will be mutually corroborating, and claims to have identified conditions which account for most cases of mutual corroboration. Combining a proposed common framework for the general study of paradoxes of positive relevance with a simulation experiment, we conclude that neither Pollock’s nor Cohen’s claims stand up to detailed scrutiny. I am quite prepared to be told…”oh, that is an extreme case: it could never really happen!” Now I have observed that this answer is always given instantly, with perfect confidence, and without any examination of the proposed case. It must therefore rest on some general principle: the mental process being something like this—“I have formed a theory. This case contradicts my theory. Therefore, this is an extreme case, and would never occur in practice.”Rev. Charles L. Dodgson. (shrink)

Objectives:Social isolation is increasing in aging societies and several studies have shown a relation with worse cognition in old age. However, less is known about the association in the oldest-old (85+); the group that is at highest risk for both social isolation and dementia. Methods:Analyses were based on follow-up 5 to 9 of the longitudinal German study on aging, cognition, and dementia in primary care patients (AgeCoDe) and the study on needs, health service use, costs, and health-related quality of life (...) in a large sample of oldest-old primary care patients (AgeQualiDe), a multi-center population-based prospective cohort study. Measurements included the Lubben Social Network Scale (LSNS-6), with a score below 12 indicating social isolation, as well as the Mini-Mental Status Examination (MMSE) as an indicator of cognitive function. Results:Dementia-free study participants (n = 942) were M = 86.4 (SD = 3.0) years old at observation onset, 68.2% were women. One third (32.3%) of them were socially isolated. Adjusted linear hybrid mixed effects models revealed significantly lower cognitive function in individuals with smaller social networks (β = 0.5, 95% CI = 0.3-0.7, p <.001). Moreover, changes in an individual's social network size were significantly associated with cognitive changes over time (β = 0.2, 95% CI = 0.1-0.4, p =.003), indicating worse cognitive function with shrinking social networks. Conclusion:Social isolation is highly prevalent among oldest-old individuals, being a risk factor for decreases in cognitive function. Consequently, it is important to maintain a socially active lifestyle into very old age. Likewise, this calls for effective ways to prevent social isolation. (shrink)

Everybody knows nowadays that the degree of development is measured according to a certain number of criteria, of which the most important one, and initially the only one. was the Gross National Product (or G.N.P.) of each country, related to the number of inhabitants. The arbitrarily-settled line some twenty years ago between the rich and the poor or, as called at that time, the “underdeveloped”, was based at the level of 1000 U. S. dollars per capita. The expression was badly (...) accepted by those it described, because development confers a dignity which cannot be refused to anybody. That is why the following euphemism appeared: “developing countries”, as promising as it is little compromising. Later on, this exclusively economical criterion was moderated by several additives, linked to social structure, to the rate of elimination of illiteracy, and even to cultural factors. (shrink)

Plotinus (204/5–270 CE) was the first and greatest of Neoplatonic philosophers. His writings were edited by his disciple Porphyry, who published them sometime between 301 and 305 CE in six sets of nine treatises each (Enneads), with a biography of his master in which he also explains his editorial principles.

Human values, by their very nature, are situational and culture specific. It would, therefore, be unrealistic to think that we can 'transplant' or 'transport' values from one country or culture to another with ease. This text identifies suitable human values which cut across national boundaries and cultures to facilitate organisations wishing to advance their businesses and strategic management capabilities towards a functionally humane organisation (FHO).

This is a collection of the key articles written by renowned Wittgenstein scholar, G.P. Baker, on Wittgenstein’s later philosophy, published posthumously. Following Baker’s death in 2002, the volume has been edited by collaborator and partner, Katherine Morris. Contains articles previously only available in other languages, and one previously unpublished paper. Completely distinct from the widely-known work Baker did with P.M.S. Hacker in the Analytical Commentary on the Philosophical Investigations.

Among the most outstanding discoveries of the last century is one that is not quite as momentous as the theory of relativity or cybernetics. It may even still be enigmatic. It has no one single author, it is not expressed in a single formula, conception, or invention. Nonetheless it is worth all the others combined.

The development of a content-full Christian bioethics requires an analysis of the particular contents and traditions which different Christians bring to morality. For Hauerwas, the content of Christian ethics is the speech and practices of the community. For Engelhardt, only a content-full tradition, such as the Orthodox tradition, will be able to arrive at closure on the moral issues presented by the contemporary practice of medicine. Capaldi calls, in contrast, for a Kantian society of autonomous self-legislators whose responsible freedom is (...) grounded in a cosmic order that must be explicated and retrieved in particular practices. The manner in which we view our own traditions and the shortcomings of modernity determine the content that Christianity brings to bioethics. (shrink)

In ‘Wittgenstein on Language and Rules’, Professor N. Malcolm took us to task for misinterpreting Wittgenstein's arguments on the relationship between the concept of following a rule and the concept of community agreement on what counts as following a given rule. Not that we denied that there are any grammatical connections between these concepts. On the contrary, we emphasized that a rule and an act in accord with it make contact in language. Moreover we argued that agreement in judgments and (...) in definitions is indeed necessary for a shared language. But we denied that the concept of a language is so tightly interwoven with the concept of a community of speakers as to preclude its applicabilty to someone whose use of signs is not shared by others. Malcolm holds that ‘This is an unwitting reduction of Wittgenstein's originality. That human agreement is necessary for “shared” language is not so striking a thought as that it is essential for language simpliciter.’ Though less striking, we believe that it has the merit of being a true thought. We shall once more try to show both that it is correct, and that it is a correct account of Wittgenstein's arguments. (shrink)

This chapter contains sections titled: The Tractatus and rules of logical syntax From logical syntax to philosophical grammar Rules and rule‐formulations Philosophy and grammar The scope of grammar Some morals.