Fitness

Discussions of “chance” and related concepts are found throughout philosophical work on evolutionary theory. By drawing attention to three very commonly-recognized distinctions, I separate four independent concepts falling under the broad heading of “chance”: randomness, epistemic unpredictability, causal indeterminism, and probabilistic causal processes. Far from a merely semantic distinction, however, it is demonstrated that conflation of these obviously distinct notions has an important bearing on debates at the core of evolutionary theory, particularly the debate over the interpretation of fitness, natural (...) selection, and genetic drift. (shrink)

One of the current problems in microbiology concerns the understanding of fitness in host-symbiont systems. A great deal of research and conceptual work has analysed how the host benefits from such associations; however, very little of this work has attempted to take the microbial perspective. Nevertheless, some scientists have argued that we should conduct more comparative studies of both microorganisms that interact with a host and their free-living counterparts in order to determine whether or not symbiosis is beneficial for these (...) microorganisms. In this paper, by means of analysing heritable symbiosis as a case study, I intend to provide a different perspective on this subject. Mainly, I argue that asking how the fitness of a given microorganism was changed during the evolution of heritable symbiosis may be theoretically unjustified at both the early and late stages of this process. The reason for this, I argue, is that, during the evolution of heritable symbiosis, the fitness of a microorganism becomes incommensurable with that of its free-living counterparts because their contexts become radically different; therefore, comparing their fitness makes little sense. My analysis is driven by the use of the ecological concept of fitness; accordingly, my conclusions are bound to this specific interpretation of fitness. (shrink)

Assembly of minimal genomes revealed many genes encoding unknown functions. Three overlooked functional categories account for some of them. Cells are prone to make errors and age. As a first key function, discrimination between proper and changed entities is indispensable. Discrimination requires management of information, an authentic, yet abstract, cur- rency of reality. For example proteins age, sometimes very fast. The cell must identify, then get rid of old proteins without destroying young ones. Implementing discrimination in cells leads to the (...) second set of functions, usually ignored. Being abstract, information must nevertheless be embodied into material entities, with unavoidable idiosyncratic properties. This brings about novel unmet needs. Hence, the buildup of cells elicits specific but awkward material implementations, ‘kludges’ that become essential under particular settings, while difficult to identify. Finally, a third functional category char- acterizes the need for growth, with metabolic implementations allowing the cell to put together the growth of its cytoplasm, membranes, and genome, spanning different spatial dimensions. Solving this metabolic quandary, critical for engineering novel synthetic biology chassis, uncovered an unexpected role for CTP synthetase as the coordinator of nonhomothetic growth. Because a significant number of SynBio constructs aim at creating cell factories we expect that they will be attacked by viruses (it is not by chance that the function of the CRISPR system was identified in industrial settings). Substantiating the role of CTP, natural selection has dealt with this hurdle via synthesis of the antimetabolite 30-deoxy-30,40-didehydro- CTP, recruited for antiviral immunity in all domains of life. (shrink)

In this work I propose a theory of evolution as a process of unfolding. This theory is based on four logically concatenated principles. The principle of evolutionary order establishes that the more complex cannot be generated from the simpler. The principle of origin establishes that there must be a maximum complexity that originates the others by logical deduction. Finally, the principle of unfolding and the principle of actualization guarantee the development of the evolutionary process from the simplest to the most (...) complex. These logical principles determine the existence of a virtual ideological matrix that contains the sequence of the preformed and folded morphogenetic fields. In this manner, the evolutionary process consists of the sequential unfolding and actualization of these fields, which is motorized by a process of teleologization carried out by the opening consciousness of the forms included in the fields of the ideological matrix. This theory leads to a radical change of perspective regarding the materialist worldview, and places life at the center of the evolutionary process as an activity carried out by a consciousness that seeks to fulfill a purpose by actualizing its own potentialities. (shrink)

Is there some general reason to expect organisms that have beliefs to have false beliefs? And after you observe that an organism occasionally occupies a given neural state that you think encodes a perceptual belief, how do you evaluate hypotheses about the semantic content that that state has, where some of those hypotheses attribute beliefs that are sometimes false while others attribute beliefs that are always true? To address the first of these questions, we discuss evolution by natural selection and (...) show how organisms that are risk-prone in the beliefs they form can be fitter than organisms that are risk-free. To address the second question, we discuss a problem that is widely recognized in statistics – the problem of over-fitting – and one influential device for addressing that problem, the Akaike Information Criterion (AIC). We then use AIC to solve epistemological versions of the disjunction and distality problems, which are two key problems concerning what it is for a belief state to have one semantic content rather than another. (shrink)

The article presents the results of a survey of Odessa residents as part of a study of the motivational and value preferences of townsfolk in the field of fitness. It has been established that the determining motives for choosing a place for fitness are the individual trainer's approach to the client, personal comfort and convenient location of the fitness club. It was revealed that respondents have an interest in innovative training, but it has not yet acquired the character of a (...) trend. We also obtained data about the significance of playing sports under the supervision of a personal trainer and sports physician. The collected empirical material served as the basis for revealing the behavioral patterns of townspeople and allowed to identify three groups of city residents who are characterized by different motivational and value preferences in the field of fitness. The first ones are focused on personal achievements, the second – on health, good physical form, good time among like-minded people, the third – on the development of special skills, achievements and opportunities to escape from problems. Based on the survey, it was also revealed that the overall physical development of the child is the leading physical motivation for children to do sports, and despite the fact that children may have certain achievements in sports, parents do not attach much importance to them. (shrink)

Michael Scriven’s (1959) example of identical twins (who are said to be equal in fitness but unequal in their reproductive success) has been used by many philosophers of biology to discuss how fitness should be defined, how selection should be distinguished from drift, and how the environment in which a selection process occurs should be conceptualized. Here it is argued that evolutionary theory has no commitment, one way or the other, as to whether the twins are equally fit. This is (...) because the theory of natural selection is fundamentally about the fitnesses of traits, not the fitnesses of token individuals. A plausible philosophical thesis about supervenience entails that the twins are equally fit if they live in identical environments, but evolutionary biology is not committed to the thesis that the twins live in identical environments. Evolutionary theory is right to focus on traits, rather than on token individuals, because the fitnesses of token organisms (as opposed to their actual survivorship and degree of reproductive success) are almost always unknowable. This point has ramifications for the question of how Darwin’s theory of evolution and R. A. Fisher’s are conceptually different. (shrink)

Il s’agit d’un excellent examen des interactions génétiques / environnement sur le comportement et, en dépit d’être un peu daté, est une lecture facile et utile. Ils commencent par des études jumelles qui montrent l’impact écrasant de la génétique sur le comportement. Ils notent les études de plus en plus connues de Judith Harris qui étendent et résument les faits que l’environnement familial partagé n’a presque aucun effet sur le comportement et que les enfants adoptés grandissent pour être aussi différents (...) de leurs demi-frères et soeurs que les personnes choisies au hasard. Un point fondamental qu’ils (et presque tous ceux qui discutent de la génétique comportementale) ne parviennent pas à noter est que les centaines (des milliers selon votre point de vue) des universels comportementaux humains, y compris toutes les bases de nos personnalités, sont 100% déterminés par nos gènes, sans aucune variation dans les normales. Tout le monde voit un arbre comme un arbre et non une pierre, cherche et mange de la nourriture, se met en colère et jaloux, etc. Donc, ce dont ils parlent surtout ici, c’est de la quantité d’environnement (culture) qui peut influer sur la mesure dans laquelle les divers traits sont montrés, plutôt que leur apparence. Enfin, ils discutent de l’eugénisme de la manière politiquement correcte habituelle, à défaut de noter que nous et tous les organismes sommes les produits de l’eugénisme de la nature et que les tentatives de vaincre la sélection naturelle avec la médecine, l’agriculture, et la civilisation dans son ensemble, sont désastreuses pour toute société qui persiste à le faire. Jusqu’à 50% de toutes les conceptions, soit environ 100 millions par an, se terminent par un avortement spontané précoce, presque tous sans que la mère soit au courant. Cet abattage naturel de gènes défectueux stimule l’évolution, nous maintient relativement génétiquement sains et rend la société possible. Dysgenics est suffisant pour détruire la civilisation, mais la surpopulation sera do ild’abord. Ceux qui souhaitent un cadre complet à jour pour le comportement humain de la vue moderne de deuxemssyst peuvent consulter mon livre 'The Logical Structure of Philosophy, Psychology, Mind and Language in Ludwig Wittgenstein et John Searle' 2nd ed (2019). Ceux qui s’intéressent à plus de mes écrits peuvent voir «Talking Monkeys --Philosophie, Psychologie, Science, Religion et Politique sur une planète condamnée --Articles et revues 2006-2017' 3rd ed (2019) et autres. (shrink)

Это отличный обзор генов / окружающей среды взаимодействия на поведение и, несмотря на то, немного от, это легко и стоит читать. Они начинаются с двойных исследований, которые показывают подавляющее влияние генетики на поведение. Они отмечают все более известные исследования Джудит Харрис, которые расширяют и обобщают факты, которые разделяют домашнюю среду, почти не влияет на поведение и что приемные дети вырастают такими же разными от своих сводных братьев и сестер, как люди, выбранные случайным образом. Один из основных моментов, что они (и (...) почти все, кто обсуждает поведенческой генетики) не отметить, что сотни (тысячи в зависимости от вашей точки зрения) человеческих поведенческих универсалий, в том числе все основы нашей личности, на 100% определяется нашими генами, без каких-либо изменений в нормах. Каждый видит дерево как дерево, а не камень, ищет и ест пищу, сердится и ревнует и т.д. Таким образом, то, что они в основном говорят о том, сколько окружающей среды (культура) может повлиять на степень, в которой различные черты показаны, а не их внешний вид. Наконец, они обсуждают евгеники в обычной политически корректной моды, не заметив, что мы и все организмы являются продуктами евгеники природы и что попытки победить естественный отбор с медициной, сельского хозяйства и цивилизации в целом, являются катастрофическими для любого общества, которое сохраняется в этом. До 50% всех зачатий, или около 100 миллионов/год, заканчиваются ранним спонтанным абортом, почти все без того, чтобы мать знала об этом. Это естественное выбраковка дефектных генов стимулирует эволюцию, сохраняет нас относительно генетически здоровыми и делает возможным общество. Дисгении достаточно, чтобы уничтожить цивилизацию, но перенаселенность будет do его впервую очередь. Те, кто желает всеобъемлющего до современных рамок для человеческого поведения из современных двух systEms зрения могут проконсультироваться с моей книгой"Логическая структура философии, психологии, Минd иязык в Людвиг Витгенштейн и Джон Сирл"2-й ред (2019). Те, кто заинтересован в более моих работ могут увидеть "Говоря обезьян - -Философия, Психология, Наука, Религия и Политика на обреченной планете - Статьи и обзоры 2006-2017' 3rd ed (2019) и другие. (shrink)

Célèbre fourmi-homme E.O. Wilson a toujours été l’un de mes héros - non seulement un biologiste exceptionnel, mais l’une des minorités minuscules et en voie de disparition des intellectuels qui ose au moins faire allusion à la vérité sur notre nature que d’autres ne parviennent pas à saisir, ou dans la mesure osant o saisir, soigneusement éviter pour l’opportunisme politique. Malheureusement, il met fin à sa longue carrière d’une manière très sordide en tant que parti à une attaque ignorante et (...) arrogante sur la science motivée au moins en partie par la ferveur religieuse de ses collègues de Harvard. Il montre les conséquences ignobles lorsque les universités acceptent l’argent de groupes religieux, les revues scientifiques sont tellement impressionnés par les grands noms qu’ils évitent l’examen par les pairs appropriés, et quand les egos sont autorisés à devenir hors de contrôle. Il nous entraîne dans la nature de l’évolution, les bases de la méthodologie scientifique, comment les mathématiques se rapportent à la science, ce qui constitue une théorie, et même quelles attitudes à la religion et la générosité sont appropriées que nous approchons inexorablement l’effondrement de la civilisation industrielle. Ceux qui souhaitent un cadre complet à jour pour le comportement humain de la vue moderne de deux systemes peuvent consulter mon livre 'The Logical Structure of Philosophy, Psychology, Mind and Language in Ludwig Wittgenstein and John Searle' 2nd ed (2019). Ceux qui s’intéressent à plus de mes écrits peuvent voir «Talking Monkeys --Philosophie, Psychologie, Science, Religion et Politique sur une planète condamnée --Articles et revues 2006-2019 3e ed (2019) et Suicidal Utopian Delusions in the 21st Century 4th ed (2020) et autres. (shrink)

Although dualism has the advantage of being intuitively plausible, it is not compatible with a 21st-century (scientific) world view. Jaak Panksepp and Antonio Damasio are contemporary writers who reject dualism, and whose views take the form of “biological naturalism”. I first discuss how their views compare in five specific respects; and then I look more closely at how the different emphases of the views affect their ability to account for the evolutionary advantages of consciousness, specifically. Both authors agree that “consciousness” (...) provides creatures with a survival advantage in terms of their ability to produce novel and/or flexible responses, their ability to plan ahead, and their motivation to promote their own survival – but the exact means by which they think these advantages are conferred, in each of these respects, differ. One might say that, whereas Damasio thinks the main evolutionary advantages of “consciousness” (the “higher reaches” of which are unique to humans) have to do with enabling creatures to work out what to do to promote their well-being, Panksepp thinks the main advantage of “consciousness” is that being “conscious” of affective feelings urgently motivates creatures to take action when their well-being is threatened. Considering that “working out what do” is only possible for a small selection of cognitively sophisticated organisms, I argue that Panksepp’s account is more plausible than Damasio’s account. (shrink)

I distinguish two roles for a fitness concept in the context of explaining cumulative adaptive evolution: fitness as a predictor of gene frequency change, and fitness as a criterion for phenotypic improvement. Critics of inclusive fitness argue, correctly, that it is not an ideal fitness concept for the purpose of predicting gene-frequency change, since it relies on assumptions about the causal structure of social interaction that are unlikely to be exactly true in real populations, and that hold as approximations only (...) given a specific type of weak selection. However, Hamilton took this type of weak selection, on independent grounds, to be responsible for cumulative assembly of complex adaptations. In this special context, I argue that inclusive fitness is distinctively valuable as a criterion for improvement and a standard for optimality. Yet to call inclusive fitness a criterion for improvement and a standard for optimality is not to make any claim about the frequency with which inclusive fitness optimization actually occurs in nature. This is an empirical question that cannot be settled by theory alone. I close with some reflections on the place of inclusive fitness in the long running clash between ‘causalist’ and ‘statisticalist’ conceptions of fitness. (shrink)

Kin selection and group selection were once seen as competing explanatory hypotheses but now tend to be seen as equivalent ways of describing the same basic idea. Yet this ‘equivalence thesis’ seems not to have brought proponents of kin selection and group selection any closer together. This may be because the equivalence thesis merely shows the equivalence of two statistical formalisms without saying anything about causality. W.D. Hamilton was the first to derive an equivalence result of this type. Yet Hamilton (...) was aware of its limitations, and saw that, while illuminating, it papered over some biologically important distinctions. Attending to these distinctions leads to the concept of ‘K-G space’, which helps us see where the biological disagreements between proponents of kin selection and group selection really lie. (shrink)

Recent literature has paid attention to a demarcation problem for evolutionary debunking arguments. This is the problem of asking in virtue of what regulative metaepistemic norm evolutionary considerations either render a belief justified, or debunk it as unjustified. I examine the so-called ‘Milvian Bridge principle’ A new science of religion, Routledge, New York, 2012; Sloan, McKenny, Eggelson Darwin in the 21st century: nature, humanity, and God, University Press, Notre Dame, 2015)), which offers exactly such a called for regulative metaepistemic norm. (...) The Milvian Bridge principle suggests that the metaepistemic norm is: adaptive reliability for truth of cognitive processes that the existence of corresponding truth-making facts evolutionary theory justifies. I argue that the Milvian Bridge principle is problematic on a number of counts, something that is shown via spiraling ‘companions in guilt arguments’. Finally, I consider ‘the core reductionist objection’ to the critique of the Milvian Bridge principle and offer a response. I conclude that the Milvian Bridge principle is destabilized. (shrink)

The topic of the relationship between the organism and its environment runs through the theories of Uexküll, Goldstein and Canguilhem with equal importance. In this work a counterpoint will be established between their theories, in the attempt to assess at which points the melodies are concordant and at which points they are discordant. As fundamental basis to his theory, Uexküll relies on the concept of conformity to a plan, which allows him to account for the congruity and perfect adjustment between (...) organisms and their Umwelten. For Goldstein and Canguilhem, the relationship between an organism and its environment resembles instead a debate or coming to terms, in which the organism, as to ensure the continuity of the state of health, must constantly create norms to maintain a productive relationship with its environment. The pinpointing of these conceptual frameworks allows to lay emphasis on that each theory relies on specific assumptions regarding teleology and sense in organisms, as well as on specific definitions of the concept of life in general. Ultimately, the view that organisms and their environments have an original and common source, a principle, or plan, which must possess all the creative characteristics of life, will be seen as prevailing. (shrink)

The modern concept of ideology was established by the liberal politician and philosopher Destutt de Tracy, with the objective of creating an all-embracing and general science of ideas, which followed the sensualist and empiricist trend initiated by Locke that culminated in the positivism of Comte. Natural selection and immunity are two key concepts in the history of biology that were strongly based on the Malthusian concept of struggle for existence. This concept wrongly assumed that population grew faster than the means (...) of existence. This “natural” law contained implicitly the idea that the poor and least gifted would not survive. This idea led to the progressive development of the concept of natural selection, whose definitive version was given by Darwin. Mechnikov took the concepts of struggle for existence and natural selection and conceived infectious diseases as a struggle between a host and its invader, the so-called phagocytosis theory. This theory created the necessity to possess mechanisms to discriminate between the own and the foreign, and led to the conception of the immune self. These concepts were not developed from ideas coming from perceptions or sensations, but from ideas coming from their values: individual interest, inevitable inequality, property, utility and profit. Values are ideals that constitute an ideological matrix which exerts a numinous activity and influence the development of our future actions. In consequence, science and its practice cannot avoid and ignore the values that drive them and impulse them towards certain directions. (shrink)

The propensity account of fitness intends to solve the classical tautologicity issue by identifying fitness with a disposition, the ability to survive and reproduce. As proponents recognized early on, this account requires operational independence from actual reproductive success to avoid circularity and vacuousness charges. They suggested that operational independence is achieved by measuring fitness values through optimality models. Our goal in this article is to develop this suggestion. We show that one plausible procedure by which these independent operationalizations could be (...) thought to take place, and which is in accordance with what is said in the optimality literature, is unsound. We provide two independent lines of reasoning to show this. We then provide a sketch of a more adequate account of the role of optimality models in evolutionary contexts and draw some consequences. (shrink)

El famoso hombre hormiga E.O. Wilson siempre ha sido uno de mis héroes-no sólo un biólogo sobresaliente, sino una de las pequeñas y desvanecida minoría de intelectuales que al menos se atreve a insinuar la verdad sobre nuestra naturaleza que otros no logran captar, o en la medida en que do comprender, evitar de manera estudiosa la conveniencia política. Tristemente, está terminando su larga carrera en una moda más sóla como parte de un ataque ignorante y arrogante a la ciencia (...) motivado al menos en parte por el fervor religioso de sus colegas de Harvard. Muestra las consecuencias viles cuando las universidades aceptan dinero de grupos religiosos, las revistas científicas están tan asombradas por los grandes nombres que evitan la revisión de pares adecuada, y cuando los egos se les permite salir de control. Nos lleva a la naturaleza de la evolución, los fundamentos de la metodología científica, cómo las matemáticas se relacionan con la ciencia, lo que constituye una teoría, e incluso qué actitudes a la religión y la generosidad son apropiadas cuando nos acercamos inexorablemente al colapso de la industria Civilización. Aquellos que deseen un marco completo hasta la fecha para el comportamiento humano de la moderna dos sistemas punto de vista puede consultar mi libros Talking Monkeys 3ª ed (2019), Estructura Logica de Filosofia, Psicología, Mente y Lenguaje en Ludwig Wittgenstein y John Searle 2a ed (2019), Suicidio pela Democracia 4ª ed (2019), La Estructura Logica del Comportamiento Humano (2019), The Logical Structure de la Conciencia (2019, Entender las Conexiones entre Ciencia, Filosofía, Psicología, Religión, Política y Economía y Delirios Utópicos Suicidas en el siglo 21 5ª ed (2019), Observaciones sobre Imposibilidad, Incompletitud, Paraconsistencia, Indecidibilidad, Aleatoriedad, Computabilidad, Paradoja e Incertidumbre en Chaitin, Wittgenstein, Hofstadter, Wolpert, Doria, da Costa, Godel, Searle, Rodych Berto, Floyd, Moyal-Sharrock y Yanofsky y otras. (shrink)

Life is the center of our existence. One would be tempted to say that first of all we live. However, our existence does not seem to pass in that modality. The exacerbated materialism in which our existence takes place, displaces life from the center of the scene. Our society is organized around production, consumerism, exploitation, efficiency, trade and propaganda. That is to say, our existence seems to have economy as the center of organization of our activities. The struggle of this (...) century that is beginning is to put life at the center of our existence, and to put economy in its proper place, that is, in the service of life. (shrink)

Darwin’s claim that Natural Selection, through optimization of fitness, explains complex biological design has not yet been properly formalized. Alan Grafen’s Formal Darwinism Project aims at providing such a formalization and at demonstrating that fitness maximization is coherent with results from Population Genetics, usually interpreted as denying it. We suggest that Grafen’s proposal suffers from some limitations linked to its concept of design as optimized fitness. In order to overcome these limitations, we propose a classification of evolutionary facts based on (...) a bi-dimensional complexity space, which adds robustness to fitness as measure of the quality of a design. In this space, each point represents an organismic architecture, and movement between two points would be an evolutionary fact. Natural Selection explains movement along the fitness axis, while non-selective mechanisms explain movement on the robustness axis. Moreover, we propose a thermodynamic metaphor to draw parallelisms between notions of fitness and entropy, robustness and energy, and movement in this space and reversible and irreversible cycles. We argue that this metaphor illustrates different evolutionary processes usually overlooked by proposals of formalization of Darwinian theory, such Grafen’s Formal Darwinism Project. (shrink)

Resumen -/- El objetivo de este trabajo consiste en analizar las relaciones entre los modelos de optimalidad y la selección natural. Defenderemos que esas relaciones pueden dividirse en dos tipos, en tanto hay dos tipos de explicaciones seleccionistas, que llamaremos “históricas” y “ahistóricas”. Las explicaciones históricas revelan como una población dada adquiere un rasgo que es adaptativo en ese ambiente e involucran muchas generaciones, variación, etc. Las explicaciones ahistóricas, explican por qué, en determinado momento, ciertos tipos de organismos tienen un (...) mayor éxito reproductivo que otros. Mostraremos que los modelos de optimalidad pueden jugar un rol en la determinación del explanandum de las explicaciones histórica seleccionistas, esto es, que ayudan a reconocer qué rasgos son adaptativos. Por otra parte, mostramos que los modelos de optimalidad nos permiten determinar a veces la parte del explanans de las explicaciones ahistóricas (particularmente, el concepto de fitness). -/- Abstract -/- The goal of this paper is to analyze the relations between optimality models and natural selection. We contend that these relationships can be divided into two kinds, as there are two kinds of natural selection explanations, which we call “historical” and “ahistorical”. Historical explanations reveal how a given population acquires a trait which is adaptive in its environment, and involves many generations, variations, etc. Ahistorical ones, explain why, at a given moment, certain kinds of organisms have a greater reproductive success than others. We show that optimality models can play a role in determining the explanandum of historical selectionist explanations, that is, they help us to recognize which traits are adaptive. And, on the other hand, that optimality models sometimes allow us to determine part of the explanans of ahistorical explanations (particularly, the concept of fitness). (shrink)

Fitness is a central concept in evolutionary theory. Just as it is central to biological evolution, so, it seems, it should be central to cultural evolutionary theory. But importing the biological fitness concept to CET is no straightforward task—there are many features unique to cultural evolution that make this difficult. This has led some theorists to argue that there are fundamental problems with cultural fitness that render it hopelessly confused. In this essay, we defend the coherency of cultural fitness against (...) those who call it into doubt. (shrink)

A new theory that naturalizes biological function is explained and compared with earlier etiological and causal role theories. Etiological theories explain functions from how they are caused over their evolutionary history. Causal role theories analyze how functional mechanisms serve the current capacities of their containing system. The new proposal unifies the key notions of both kinds of theories, but goes beyond them by explaining how functions in an organism can exist as factors with autonomous causal efficacy. The goal-directedness and normativity (...) of functions exist in this strict sense as well. The theory depends on an internal physiological or neural process that mimics an organism’s fitness, and modulates the organism’s variability accordingly. The structure of the internal process can be subdivided into subprocesses that monitor specific functions in an organism. The theory matches well with each intuition on a previously published list of intuited ideas about biological functions, including intuitions that have posed difficulties for other theories. (shrink)

Is there any way to reconcile the adaptationist’s image of natural selection as an engine of optimality with the more complex image of its dynamics we get from population genetics? This has long been an important strand in the controversy surrounding adaptationism, yet debate has been hampered by a tendency to conflate various different ways of thinking about maximization. Here I distinguish four varieties of maximization principle. I then discuss the logical relations between these varieties, arguing that, although they may (...) seem similar at face value, none entails any of the others. I then turn briefly to the status of each variety, arguing that, while each type of maximization principle faces serious problems, the problems are subtly different for each type. In the last section, I reflect on what is at stake in the debate. (shrink)

Hamilton introduced two conceptions of social fitness, which he called neighbour-modulated fitness and inclusive fitness. Although he regarded them as formally equivalent, a re-analysis of his own argument for their equivalence brings out two important assumptions on which it rests: weak additivity and actor's control. When weak additivity breaks down, neither fitness concept is appropriate in its original form. When actor's control breaks down, neighbour-modulated fitness may be appropriate, but inclusive fitness is not. Yet I argue that, despite its more (...) limited domain of application, inclusive fitness provides a distinctively valuable perspective on social evolution. (shrink)

The notion that natural selection is a process of fitness maximization gets a bad press in population genetics, yet in other areas of biology the view that organisms behave as if attempting to maximize their fitness remains widespread. Here I critically appraise the prospects for reconciliation. I first distinguish four varieties of fitness maximization. I then examine two recent developments that may appear to vindicate at least one of these varieties. The first is the ‘new’ interpretation of Fisher's fundamental theorem (...) of natural selection, on which the theorem is exactly true for any evolving population that satisfies some minimal assumptions. The second is the Formal Darwinism project, which forges links between gene frequency change and optimal strategy choice. In both cases, I argue that the results fail to establish a biologically significant maximization principle. I conclude that it may be a mistake to look for universal maximization principles justified by theory alone. A more promising approach may be to find maximization principles that apply conditionally and to show that the conditions were satisfied in the evolution of particular traits. (shrink)

In this article, I argue that we should revise our understanding of physical fitness to include preparation for challenging physically mediated life experiences—such as aging, disability, illness, reproduction, and death—as an important goal of physical activity. Such a revision is needed because the messages about fitness we encounter through “fitness ideology” can undermine the cultivation of skills and perspectives important for finding meaning, equanimity, and even happiness in light of such experiences. Because one of the ways that fitness ideology undermines (...) personal growth and well-being is through the promotion of fear and denial of our mutability and mortality, I focus on death, generally the most... (shrink)

This special issue of IJFAB starts from the premise that fitness is a feminist issue, and, more specifically, it is an issue that ought to be of concern to feminists interested in bioethics. While a neglected concept in feminist bio-ethics, fitness is of key importance to women’s health and well-being. Not only that, it is also an area of women’s lives that invites unwelcome policing and advice from friends, family members, medical practitioners, and even strangers. People have a difficult time (...) prying apart the idea of fitness from that of weight loss. Most women who embark on a fitness routine have weight loss among their primary goals.Since late 2011, we and a host of guest authors have been exploring the... (shrink)

ABSTRACT In social evolution theory, biological individuals are often represented on the model of rational agents, that is, as if they were ‘seeking’ to maximize their own reproductive success. In the 1990s, important criticisms of this mode of thinking were made by Brian Skyrms and Elliott Sober, who both argued that ‘rational agent’ models can lead to incorrect predictions when there are positive correlations between individuals’ phenotypes. In this article, I argue that one model of rational choice—namely, Savage’s model —can (...) actually be vindicated in evolutionary biology, provided that the pay-offs are computed in inclusive fitness terms. I also show that the use of this model is better avoided when pay-offs are non-additive, or when certain causal influences affect the outcome of natural selection. The result is a partial rehabilitation of this mode of thinking, conditional on both the additivity of the pay-off structure and the absence of any form of manipulation or coercion. _1_ Introduction _2_ When Natural Selection and Rational Deliberation Part Ways _3_ A Simple Solution: Redefining the Pay-offs in Inclusive Fitness Terms _4_ Sober on Inclusive Fitness Maximization _5_ Inclusive Fitness with Non-additive Pay-offs _6_ Causal Influences and the Savage– Hamilton Model _6.1_ Reciprocity and partner choice _6.2_ Coercion and manipulation _7_ Conclusion Appendix. (shrink)

I argue that the propensity interpretation of fitness, properly understood, not only solves the explanatory circularity problem and the mismatch problem, but can also withstand the Pandora’s box full of problems that have been thrown at it. Fitness is the propensity (i.e., probabilistic ability, based on heritable physical traits) for organisms or types of organisms to survive and reproduce in particular environments and in particular populations for a specified number of generations; if greater than one generation, “reproduction” includes descendants of (...) descendants. Fitness values can be described in terms of distributions of propensities to produce varying number of offspring and can be modeled for any number of generations using computer simulations, thus providing both predictive power and a means for comparing the fitness of different phenotypes. Fitness is a causal concept, most notably at the population level, where fitness differences are causally responsible for differences in reproductive success. Relative fitness is ultimately what matters for natural selection. (shrink)

Over the past decade philosophers of biology have discussed whether evolutionary theory is a causal theory or a phenomenological study of evolution based solely on the statistical features of a population. This article reviews this controversy from three aspects, respectively concerning the assumptions, applications, and explanations of evolutionary theory, with a view to arriving at a definite conclusion in each contention. In so doing I also argue that an implicit methodological assumption shared by both sides of the debate, namely the (...) overconfidence in conceptual analysis as a tool to understand the scientific theory, is the real culprit that has both generated the problem and precluded its solution for such a long time. (shrink)

One contentious debate in the philosophy of biology is that between the statisticalists and causalists. The former understand core evolutionary concepts like fitness and selection to be mere statistical summaries of underlying causal processes. In this view, evolutionary changes cannot be causally explained by selection or fitness. The causalist side, on the other hand, holds that populations can change in response to selection—one can cite fitness differences or driftability in causal explanations of evolutionary change. But, on the causalist side, it (...) is often not clear how, precisely, one should understand these causes. Thus, much more could be said about what sort of causes fitness and driftability are. In this paper, I borrow Dretske's distinction between structuring and triggering causes and I suggest that fitness and driftability are structuring causes of evolution. (shrink)

Evolutionary biology since Darwin has seen a dramatic entrenchment and elaboration of the role of chance in evolution. It is nearly impossible to discuss contemporary evolutionary theory in any depth at all without making reference to at least some concept of “chance” or “randomness.” Many processes are described as chancy, outcomes are characterized as random, and many evolutionary phenomena are thought to be best described by stochastic or probabilistic models. Chance is taken by various authors to be central to the (...) understanding of fitness, genetic drift, macroevolution, mutation, foraging theory, and environmental variation, to take but a few examples. And for each of these notions, there are yet more stories to tell. Each weaves itself into the various branches of evolutionary theory in myriad different ways, with a wide variety of effects on the history and current state of life on Earth. Each is grounded in a particular trajectory in the history of philosophy and the history of biology, and has inspired a variety of responses throughout science and culture. This book endeavors to offer a cross-section of biological, historical, philosophical, and theological approaches to understanding chance in evolutionary theory. (shrink)

“Look Great Naked!” “Sexy Legs Now!” “Score a Perfect 10 Body!” These invitations appear regularly on the covers of glossy fitness magazines, always beside a photograph of a too-perfect-not-to-be-airbrushed, generally scantily clad, young woman. Are they really invitations or are they imperatives? What should we make of the apparently presumed connection between fitness and sex? These are the questions that drive this article, in which we distinguish between fitness and sport and provide a feminist account of fitness to set the (...) stage for analysis of the conflict between norms of femininity and heteronormativity in sport and in the fitness industry. We examine the medicalization of fitness to show that women’s... (shrink)

Yes, fitness is the central concept of evolutionary biology, but it is an elusive concept. Almost everyone who looks at it seriously comes out in a different place.

The concepts of adaptation and fitness have such an appeal that they have been used in other scientific domains, including the social sciences. One particular aspect of this theory transfer concerns the so-called fitness landscape models. At first sight, fitness landscapes visualize how an agent, of any kind, relates to its environment, how its position is conditional because of the mutual interaction with other agents, and the potential routes towards improved fitness. The allure of fitness landscapes is first and foremost (...) that it represents a complex story about adaptation and fitness in one coherent image. Different accounts of fitness landscapes in different domains in the social sciences suggest that the properties and functions of fitness landscapes are attributed rather freely. These differences are testimony of the model’s versatility. At the same time, one will notice that the different approaches can also create ambiguity about the exact meaning and role of fitness landscapes in the social sciences. This article presents an extensive literature survey of the diverging interpretations and uses of fitness landscapes in the social sciences and discusses the implications in terms of how these models inform scientific inquiry. (shrink)

Fitness is a central theoretical concept in evolutionary theory. Despite its importance, much debate has occurred over how to conceptualize and formalize fitness. One point of debate concerns the roles of organismic and trait fitness. In a recent addition to this debate, Elliott Sober argues that trait fitness is the central fitness concept, and that organismic fitness is of little value. In this paper, by contrast, we argue that it is organismic fitness that lies at the bases of both the (...) conceptual role of fitness, as well as its role as a measure of evolutionary dynamics. (shrink)

Dans cet article, je présente une approche sémantique de l’analyse de la fonction de la métaphore du paysage dans la biologie de l’évolution. Le concept de paysage adaptatif a suscité une attention considérable dans la philosophie de la biologie récente. La plupart des auteurs ont considéré ce concept de l’une des deux manières suivantes: en tant qu’outil heuristique, comme partie intrinsèque de modèles mathématiques robustes, ou comme un ensemble définissable d’analogies sur lesquelles les modèles sont basés et testés. Chacune de (...) ces visions conduit à la conclusion que la valeur de la métaphore du paysage dépend seulement du succès des modèles que sous-tend la métaphore, en vue de représenter adéquatement la dynamique de l’évolution. J’essaie de montrer que cette conclusion, ainsi que les visions qui y conduisent, ne tiennent pas compte d’épisodes importants dans l’histoire de la métaphore du langage. Ces visions proviennent plutôt de thèses générales, en philosophie des sciences, quant au rôle des métaphores dans les théories scientifiques. L’analyse sémantique que je propose met en lumière le fait que la fonction première du concept de relief adaptatif, au cours de la synthèse évolutionniste, a été de servir de cadre général d’unification conceptuelle, qui a rendu possible la conciliation de phénomènes empiriques hétérogènes. De ce point de vue, la métaphore du paysage est un outil linguistique-théorique qui ne doit pas être abandonné (et qui ne l’est de fait pas) suite à la falsification des modèles construits et interprétés au moyen de la métaphore. (shrink)

Competition over reproductive opportunities among members of one sex often harms the opposite sex, creating a conflict of interest between individual males and females. Recently, this battle of the sexes has become a paradigm in the study of intersexual coevolution. Here, we review recent theoretical and empirical advances suggesting that – as in any scenario of intraspecific competition – selfishness (competitiveness) can be influenced by the genetic relatedness of competitors. When competitors are positively related (e.g. siblings), an individual may refrain (...) from harming its competitor(s) and their mate(s) because this can improve the focal individual's inclusive fitness. These findings reveal that population genetic structure might be of paramount importance when studying the battle of the sexes. We conclude by identifying some new lines of research at the interface of sexual selection and social evolution. (shrink)

Starting with Aristotle and moving on to Darwin, Marco Solinas outlines the basic steps from the birth, establishment and later rebirth of the traditional view of living beings, and its overturning by evolutionary revolution. The classic framework devised by Aristotle was still dominant in the 17th Century world of Galileo, Harvey and Ray, and remained hegemonic until the time of Lamarck and Cuvier in the 19th Century. Darwin's breakthrough thus takes on the dimensions of an abandonment of the traditional finalistic (...) theory. It was a transition exemplified in the morphological analysis of useless parts, such as the sightless eyes of moles, already discussed by Aristotle, which Darwin used as a crowbar to unhinge the systematic recourse to final causes. With many excerpts, a chronological sequence and an analytical approach, this book follows the course of the two conceptions that have shaped the destiny of life sciences in western culture. (shrink)

Biological organisms appear to have agency, goals, and meaningful behaviour. One possibility is that this is mere appearance, where such properties are not real, but only ‘as if’ consequences of the physiological structure of organisms. Another possibility is that these properties are real, as emerging from the organism's structure and from how the organism interacts with its environment. Here I will discuss a recent theory showing that the latter position is most likely correct, and argue that the theory is largely (...) consistent with the basics of the field of biosemiotics. The theory can be represented as a triad that resembles the semiotic triad proposed by Peirce, which connects a sign with its object through a process of interpretation. In the theory presented, the sign is an internalized version of fitness which refers to the true fitness through a feedback loop that in effect produces interpretation. The feedback loop entangles deterministic and stochastic forms of causation in such a way that genuine agency, goal-directedness, and their associated meaning emerge. It produces a strong form of emergence not reducible to its constituents. The result is that novel phenomena arise that are real and necessary components for a complete understanding of living organisms. (shrink)

Living organisms appear to have agency, the ability to act freely, and humans appear to have free will, the ability to rationally decide what to do. However, it is not clear how such properties can be produced by naturalistic processes, and there are indeed neuroscientific measurements that cast doubt on the existence of free will. Here I present a naturalistic theory of agency, consciousness, and free will. Elementary forms of agency evolved very early in the evolution of life, utilizing an (...) extension of the basic Darwinian scheme that combines and entangles deterministic and stochastic causation. The extension effectively produces an active form of causation, as well as meaning intrinsic to the organism. Consciousness arose when animals evolved advanced nervous systems and social lifestyles that enabled communication mutually affecting each animal’s intrinsic meaning. I argue that various forms of agency that subsequently arose in evolution, preconscious, conscious, intelligent, symbolic, and rational agency, still coexist in humans. This coexistence, combined with the fact that agency is not instantaneous but takes time to build up, makes simple interpretations of neuroscientific results on free will problematic. The conclusion of the study is that conscious free will, including a form of agent causation, is fully consistent with a naturalistic world-view and can be produced by the specific processes discussed. The result closely resembles existing approaches to life and mind that are inspired by phenomenology. (shrink)

Cooperation is rife in the microbial world, yet our best current theories of the evolution of cooperation were developed with multicellular animals in mind. Hamilton’s theory of inclusive fitness is an important case in point: applying the theory in a microbial setting is far from straightforward, as social evolution in microbes has a number of distinctive features that the theory was never intended to capture. In this article, I focus on the conceptual challenges posed by the project of extending Hamilton’s (...) theory to accommodate the effects of gene mobility. I begin by outlining the basics of the theory of inclusive fitness, emphasizing the role that the concept of relatedness is intended to play. I then provide a brief history of this concept, showing how, over the past fifty years, it has departed from the intuitive notion of genealogical kinship to encompass a range of generalized measures of genetic similarity. I proceed to argue that gene mobility forces a further revision of the concept. The reason in short is that, when the genes implicated in producing social behaviour are mobile, we cannot talk of an organism’s genotype simpliciter; we can talk only of an organism’s genotype at a particular stage in its life cycle. We must therefore ask: with respect to which stage(s) in the life cycle should relatedness be evaluated? For instance: is it genetic similarity at the time of social interaction that matters to the evolution of social behaviour, or is it genetic similarity at the time of reproduction? I argue that, strictly speaking, it is neither of these: what really matters to the evolution of social behaviour is diachronic genetic similarity between the producers of fitness benefits at the time they produce them and the recipients of those benefits at the end of their life-cycle. I close by discussing the implications of this result. The main payoff is that it makes room for a possible new mechanism for the evolution of altruism in microbes that does not require correlated interaction among bearers of the genes for altruism. The importance of this mechanism in nature remains an open empirical question. (shrink)

One key aim of Grafen’s Formal Darwinism project is to formalize ‘modern biology’s understanding and updating of Darwin’s central argument’. In this commentary, I consider whether Grafen has succeeded in this aim.

Inclusive fitness theory provides conditions for the evolutionary success of a gene. These conditions ensure that the gene is selfish in the sense of Dawkins (The selfish gene, Oxford University Press, Oxford, 1976): genes do not and cannot sacrifice their own fitness on behalf of the reproductive population. Therefore, while natural selection explains the appearance of design in the living world (Dawkins in The blind watchmaker: why the evidence of evolution reveals a universe without design, W. W. Norton, New York, (...) 1996), inclusive fitness theory does not explain how. Indeed, Hamilton’s rule is equally compatible with the evolutionary success of prosocial altruistic genes and antisocial predatory genes, whereas only the former, which account for the appearance of design, predominate in successful organisms. Inclusive fitness theory, however, permits a formulation of the central problem of sociobiology in a particularly poignant form: how do interactions among loci induce utterly selfish genes to collaborate, or to predispose their carriers to collaborate, in promoting the fitness of their carriers? Inclusive fitness theory, because it abstracts from synergistic interactions among loci, does not answer this question. Fitness-enhancing collaboration among loci in the genome of a reproductive population requires suppressing alleles that decrease, and promoting alleles that increase the fitness of its carriers. Suppression and promotion are effected by regulatory networks of genes, each of which is itself utterly selfish. This implies that genes, and a fortiori individuals in a social species, do not maximize inclusive fitness but rather interact strategically in complex ways. It is the task of sociobiology to model these complex interactions. (shrink)

Individual-as-maximizing agent analogies result in a simple understanding of the functioning of the biological world. Identifying the conditions under which individuals can be regarded as fitness maximizing agents is thus of considerable interest to biologists. Here, we compare different concepts of fitness maximization, and discuss within a single framework the relationship between Hamilton’s (J Theor Biol 7:1–16, 1964) model of social interactions, Grafen’s (J Evol Biol 20:1243–1254, 2007a) formal Darwinism project, and the idea of evolutionary stable strategies. We distinguish cases (...) where phenotypic effects are additive separable or not, the latter not being covered by Grafen’s analysis. In both cases it is possible to define a maximand, in the form of an objective function ϕ(z), whose argument is the phenotype of an individual and whose derivative is proportional to Hamilton’s inclusive fitness effect. However, this maximand can be identified with the expression for fecundity or fitness only in the case of additive separable phenotypic effects, making individual-as-maximizing agent analogies unattractive (although formally correct) under general situations of social interactions. We also feel that there is an inconsistency in Grafen’s characterization of the solution of his maximization program by use of inclusive fitness arguments. His results are in conflict with those on evolutionary stable strategies obtained by applying inclusive fitness theory, and can be repaired only by changing the definition of the problem. (shrink)