Nature and Nurture

The problem of variability concerns the fact that empirical data does not support the existence of a coordinated set of biological markers, either in the body or the brain, which correspond to our folk emotion categories; categories like anger, happiness, sadness, disgust and fear. Barrett (2006a, b, 2013, 2016, 2017a, b) employs this fact to argue (i) against the faculty psychology approach to emotion, e.g. emotions are the products of emotion-specific mechanisms, or “modules”, and (ii) for the view that emotions (...) are constructed from domain-general “core systems” with the aid of our folk concepts. The conjunction of (i) and (ii), she argues, heralds a paradigm shift in our understanding of emotion: emotions aren’t triggered but made. In this paper, I argue such a shift is premature for a faculty psychology framework can accommodate the neurobiological variability of emotion. This can be done by treating emotions as developmental modules: non-innate systems which behave like modules, but form as a product of ontogenetic development. (shrink)

Disputes about the causal structure of natural selection have implications for teleosemantics. Etiological, mainstream teleosemantics is based on a causalist view of natural selection. The core of its solution to Brentano’s Problem lies in the solution to Kant’s Puzzle provided by the Modern Synthesis concerning populational causation. In this paper, I suggest that if we adopt an alternative, statisticalist view on natural selection, the door is open for two reflections. First, it allows for setting different challenges to etiological teleosemantics that (...) arise if a statisticalist reading of natural selection is right. Second, by providing a different solution to Kant’s Puzzle based on individual causes of evolution, statisticalism promotes a different answer to Brentano’s Problem, what I label as Agential Teleosemantics. (shrink)

ENG: We all have our own ideas about what it is like to be intelligent. Indeed, even the experts disagree on this topic. This has generated diverse theories on the nature of intelligence and its genetic and environmental bases. Many scientific and philosophical questions thus remain unaddressed: is it possible to characterize intelligence in scientific terms? What do IQ tests measure? How is intelligence influenced by genetics, epigenetics, and the environment? What are the ethical and social implications of the research (...) on this topic? This book aims to provide the readers with the conceptual resources to critically analyze scientific findings and orientate themselves in this multi-faceted debate across biology, psychology, neuroscience, philosophy, and anthropology. -/- ITA: Ognuno di noi ha una propria idea di cosa significhi essere intelligenti, tanto che anche gli scienziati esperti in materia hanno opinioni differenti al riguardo. Ciò ha contribuito a generare teorie contrastanti sulla natura dell’intelligenza e su quali siano le sue basi genetiche e ambientali. Non è un caso, dunque, che diverse domande scientifiche e filosofiche restino ancora aperte: è possibile caratterizzare scientificamente l’intelligenza? Cosa misurano i test del QI? In che modo genetica, epigenetica e ambiente influenzano l’intelligenza? Quali sono le implicazioni etiche e sociali della ricerca sull’argomento? Oltre ad analizzare questi problemi, il testo intende fornire gli strumenti concettuali necessari per leggere criticamente i dati scientifici e orientarsi in uno sfaccettato e affascinante dibattito a cavallo tra biologia, psicologia, neuroscienze, filosofia e antropologia. (shrink)

In 1976, the Genetics Society of America published a document entitled “Resolution of Genetics, Race, and Intelligence.” This document laid out the Society’s position in the IQ controversy, particularly that on scientific and ethical questions involving the genetics of intellectual differences between human populations. Since the GSA was the largest scientific society of geneticists in the world, many expected the document to be of central importance in settling the controversy. Unfortunately, the Resolution had surprisingly little influence on the discussion. In (...) 1979, William Provine analyzed the possible factors that decreased the impact of the Resolution, among them scientists’ limited understanding of the relationship between science and ethics. Through the analysis of unpublished versions of the Resolution and exchanges between GSA members, I will suggest that the limited impact of the statement likely depended on a shift in the aims of the GSA due to the controversies that surrounded the preparation of the document. Indeed, the demands of the membership made it progressively more impartial in both scientific and political terms, decreasing its potential significance for a wider audience. Notably, the troubled history of the Resolution raises the question of what can make effective or ineffective the communication between scientists and the public—a question with resonance in past and present discussions on topics of social importance. (shrink)

The author analyzes the origin and meaning of the expression ‘Ethics of Sexual Difference’ (ESD), contextualising it in the paradigm ‘thought of Sexual Difference’, in which the potentiality and aporias arising from the debate within the feminist movement are highlighted. Possible interpretations of these ethics, developed in the Italian philosophical context, are illustrated and evaluated. The author proposes a critical comparison with other models, for example, the queer theories, and attempts to show how the ‘Thought of Sexual Difference’ (TSD) opens (...) itself to destabilization produced by the emergence of new subjects (gay and lesbian, transgender, intersex) and their corresponding scientific knowledge. The author therefore proposes an update to the plural, ‘Ethics of Sexual Differences’ (ESDs), listing the possible methodological and content assumptions (including the development of a relational model in all scientific disciplines) and the disciplinary implications (also in the psychoanalytic field) of an ethics so defined. A reference is made to the discussion of socalled "gender ideology", in which the protagonists have often showed a certain difficulty in implementing an ESDs. (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)

Has science already answered the fundamental questions about the concepts of Life, Cosmos and Evolution? Has science not relegated these fundamental questions by following up on more immediate, “useful” and practical endeavors that ultimately ensure that the wheel of capitalism keeps spinning in its frantic search for material and economic progress? There is something terribly wrong with the current theory of evolution, understood as the Darwinian theory with its successive versions and extensions. The concept of natural selection, the cornerstone of (...) Darwinism, is logically inconsistent. This has been demonstrated in some of my latest academic publications. The entire conceptual framework of Darwinism is inadequate. Organisms do not compete with each other for the survival of the fittest. The fundamental relationship in Nature is not competition or confrontation, but interconnectivity, complementarity, and relational meaningfulness. A new theory of evolution is necessary to explain how it is possible that organisms as simple as bacteria, protozoa and diatoms could have generated organisms as complex as primates, and among them, the human being, a being capable of feeling and thinking, of suffering and enjoying, a being capable of having ideals and purposes. A theory that explains how it is possible that this being so complex, rich, and to some extent still unknown, has emerged from a single cell, an egg-cell, lacking all the capacities, riches and depths of human existence. Such a theory already exists. (shrink)

ITA: In questo articolo analizzerò la differenza tra il concetto di ereditarietà e quello di ereditabilità. In primo luogo, evidenzierò come i due concetti derivino storicamente da differenti tradizioni nello studio della variabilità fenotipica e del rapporto genotipo-fenotipo. Secondariamente, illustrerò gli aspetti teorici e metodologici alla base dei due concetti, che sono peraltro collegati a differenti aree delle scienze biologiche. Infine, spiegherò brevemente come si sia recentemente tentato, con molte difficoltà, di connettere lo studio dei meccanismi dell’ereditarietà allo studio dell’ereditabilità. (...) Nel discutere le questioni di cui sopra, farò riferimento a tratti psicologici come l’intelligenza dal momento che è proprio dallo studio di questo tipo di tratti che sono emersi i maggiori problemi teorici e metodologici, nonché le controversie più intense. -/- ENG: In this paper, I analyse the distinction between heredity and heritability. First, I highlight that the two concepts derive from different historical traditions in the study of phenotypic variability and of the genotype-phenotype relationship. Second, I illustrate the theoretical and methodological aspects connected to the two concepts, which are traditionally associated with different areas of biological research. Then, I focus on recent attempts aimed at connecting with each other the analysis of heredity and of heritability. In my discussion, I shall often refer to human psychological traits such as intelligence. Indeed, most theoretical and methodological discussions have emerged with respect to the study of these traits. (shrink)

Molecular developmental biology has expanded our conceptions of gene actions, underpinning that embryonic development is not only governed by a set of specific genes, but as much by space–time conditions of its developing modules. Typically, formation of cellular spheres, their transformation into planar epithelia, followed by tube formations and laminations are modular steps leading to the development of nervous tissues. Thereby, actions of organising centres, morphogenetic movements, inductive events between epithelia, tissue polarity reversal, widening of epithelia, and all these occurring (...) orderly in space and time, are driving forces of emergent laminar neural tissues, e.g. the vertebrate retina. Analyses of self-organisational formation of retina-like 3D structures from dispersed cells under defined cell culture conditions demonstrate that not only particular genetic networks, but—at least as important—the applied culture conditions define phenotypes of emergent tissues. Such in vitro approaches allow assigning emerging tissue formation to ground-laying genetic networks separately from contributions by conditional constraints. (shrink)

The so-called “Baldwin Effect” has been studied for years in the fields of Artificial Life, Cognitive Science, and Evolutionary Theory across disciplines. This idea is often conflated with genetic assimilation, and has raised controversy in trans-disciplinary scientific discourse due to the many interpretations it has. This paper revisits the “Baldwin Effect” in Baldwin’s original spirit from a joint historical, theoretical and experimental approach. Social Heredity – the inheritance of cultural knowledge via non-genetic means in Baldwin’s term – is also taken (...) into consideration. I shall argue that the Baldwin Effect can occur via social heredity without necessity for genetic assimilation. Computational experiments are carried out to show that when social heredity is permitted with high fidelity, there is no need for the assimilation of acquired characteristics; instead the Baldwin Effect occurs as promoting more plasticity to facilitate future intelligence. The role of mind and intelligence in evolution and its implications in an extended synthesis of evolution are briefly discussed. (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)

Culture or Biology? The question can seem deep and important. Yet, I argue in this chapter, if you are enthralled by questions about our biological differences, then you are probably confused. My goal is to diagnose the confusion. In debates about the role of biology in the social world it is easy to ask the wrong questions, and it is easy to misinterpret the scientific research. We are intuitively attracted to what is called psychological essentialism, and therefore interpret what is (...) biological as what can be traced to “essences”. On this interpretation, it would be deep and important to know what about, say, the differences between the genders is biological: it would correspond to what is essential to being a man or being a woman, and be opposed to what is a mere accidental feature that some women or some men have. Yet, the psychological essentialist understanding of ‘biological differences’ is deeply mistaken about biology. It has the wrong conception of biological kinds, of biological heritability, and of how genes and hormones work. Those who argue for an important role of ‘biology’ in the explanation of human differences often see ‘the science’ on their side. But this is false – on the interpretation of ‘biological differences’ that is most intuitive and that makes the question appear to be most interesting. Defenders of ‘biology’ often have the science against them. What is often called ‘biology’ is a myth: a myth created by an intuitive tendency that grotesquely distorts real biological research. (shrink)

The model of human intelligence that is most widely adopted derives from psychometrics and behavioral genetics. This standard approach conceives intelligence as a general cognitive ability that is genetically highly heritable and describable using quantitative traits analysis. The paper analyzes intelligence within the debate on natural kinds and contends that the general intelligence conceptualization does not carve psychological nature at its joints. Moreover, I argue that this model assumes an essentialist perspective. As an alternative, I consider an HPC theory of (...) intelligence and evaluate how it deals with essentialism and with intuitions coming from cognitive science. Finally, I highlight some concerns about the HPC model as well, and conclude by suggesting that it is unnecessary to treat intelligence as a kind in any sense. (shrink)

Die Frage nach der Vererbung von Eigenschaften bei Lebewesen beschäftigt den Menschen seit alters her: das ist Genetik. Auch lange schon beschäftigen sich Biologen mit der Frage, wie sich die vielen Tierarten im Laufe einer langen Stammesgeschichte herausbilden konnten: das ist Evolution. Wie wird Konstantes über Generationen bewahrt und Diverses/Neues eingeführt? Die überragenden Erfolge der Genetik haben uns im Glauben eingelullt, wir hätten diese Prozesse vollständig verstanden. Mit dem Aufkommen der so genannten Epigenetik kommen Grundlagen sowohl der Individual-, wie auch (...) der Stammesentwicklung jedoch wieder ins Schwanken. In diesem Artikel will ich einen kleinen Einblick in das Feld der Epigenetik und ihre gesellschaftliche Relevanz geben. (shrink)

Developmental systems theory (DST) is a wholeheartedly epigenetic approach to development, inheritance and evolution. The developmental system of an organism is the entire matrix of resources that are needed to reproduce the life cycle. The range of developmental resources that are properly described as being inherited, and which are subject to natural selection, is far wider than has traditionally been allowed. Evolution acts on this extended set of developmental resources. From a developmental systems perspective, development does not proceed according to (...) a preformed plan; what is inherited is much more than DNA; and evolution is change not only in gene frequencies, but in entire developmental systems. (shrink)

One of the most important recent developments in the study of concepts has been the resurgence of interest in nativist accounts of the human conceptual system. However, many theorists suppose that a key feature of neural organization—the brain’s plasticity—undermines the nativist approach to concept acquisition. We argue that, on the contrary, not only does the brain’s plasticity fail to undermine concept nativism, but a detailed examination of the neurological evidence actually provides powerful support for concept nativism.

In this paper, I examine Aristotle's notion of potentiality as it applies to the beginning of life. Aristotle’s notion of natural kinēsis implies that we should not treat the entity at the beginning of embryonic development as human, or indeed as the same as the one that is born. This leads us to ask: When does the embryo turn into a human? Aristotle’s own answer to this question is very harsh. Bracketing the views that lead to this harsh answer, his (...) theory of kinēsis still gives us reason for searching for a replacement answer. Aristotle’s own work unfortunately gives us no help in finding this answer. (shrink)

The organism against its environment. The organism against other organisms, competing and struggling for life. Antagonism and confrontment as the only possible relation in nature. The tendency to anthropomorphize nature and explain it using concepts and facts from the human sphere. A stroll through the worlds of Uexküll and Merleau-Ponty in the search of alternative knowledge that allow us to understand relation from another point of view. A counterpoint and identification of common tonalities between the research programs from both thinkers (...) as a way to demonstrate the possibilities of a more fruitful approach. Umwelt as a generative system of meaningful relations in which its participants are not mutually exclusive, but express a melody that include them all. (shrink)

This chapter deals with the way our psychology and actions a scaffolded by their environment but also the tensions that can appear between individual and environment, both at the level of biology and culture. The chapter is grounded in an analysis of the early 20th century theoretical biologist Jacob von Uexkull and his notion of "Umwelt" or "surround world". But also raises the question of whether organisms fit their environment as neatly as Uexkull and many later thinkers have proposed or (...) assumed. (shrink)

Kant argued that Euclidean geometry is synthesized on the basis of an a priori intuition of space. This proposal inspired much behavioral research probing whether spatial navigation in humans and animals conforms to the predictions of Euclidean geometry. However, Euclidean geometry also includes concepts that transcend the perceptible, such as objects that are infinitely small or infinitely large, or statements of necessity and impossibility. We tested the hypothesis that certain aspects of nonperceptible Euclidian geometry map onto intuitions of space that (...) are present in all humans, even in the absence of formal mathematical education. Our tests probed intuitions of points, lines, and surfaces in participants from an indigene group in the Amazon, the Mundurucu, as well as adults and age-matched children controls from the United States and France and younger US children without education in geometry. The responses of Mundurucu adults and children converged with that of mathematically educated adults and children and revealed an intuitive understanding of essential properties of Euclidean geometry. For instance, on a surface described to them as perfectly planar, the Mundurucu's estimations of the internal angles of triangles added up to ∼180 degrees, and when asked explicitly, they stated that there exists one single parallel line to any given line through a given point. These intuitions were also partially in place in the group of younger US participants. We conclude that, during childhood, humans develop geometrical intuitions that spontaneously accord with the principles of Euclidean geometry, even in the absence of training in mathematics. (shrink)

International Studies in the Philosophy of Science, Volume 25, Issue 4, Page 417-420, December 2011.

Political imputations in science are notoriously a tricky business. I addressed this issue in the context of the nature–nurture debate in the penultimate chapter of my book Making Sense of Heritability (Cambridge U. P. 2005). Although the book mainly dealt with the logic of how one should think about heritability of psychological differences, it also discussed the role of politics in our efforts to understand the dynamics of that controversy. I first argued that if a scholar publicly defends a certain (...) view (say, hereditarianism) in the debate about IQ, race and genetics this fact alone cannot justify attributing a political motivation to that person. But then later I suggested that the pressure of political correctness could explain some peculiarities of the contemporary controversy about the heritability of group differences in IQ. Several reviewers of my book raised a tu quoque objection. Am I not doing here the same thing that I condemn others for? (shrink)

Human simultaneously is the acting person of a few autonomous and interdepending forms of evolutional process. Accordingly, it is possible to select three forms of adaptation and three constituents of evolutional strategy of survival of humanity – biological, sociocultural and technological adaptations. The actual and potential consequences of development of so-called High Hume technologies (technologies of the guided evolution)  most essential from major technological adaptations of humanity  are analyzed. The phenomenon of bio-power within the framework of global coevolutional (...) methodology as one of central elements of mechanism of mutual co-ordination of biological and sociocultural forms of evolutional process from one side and technocultural balance, with other is examined. (shrink)

This article illustrates in which sense genetic determinism is still part of the contemporary interactionist consensus in medicine. Three dimensions of this consensus are discussed: kinds of causes, a continuum of traits ranging from monogenetic diseases to car accidents, and different kinds of determination due to different norms of reaction. On this basis, this article explicates in which sense the interactionist consensus presupposes the innate?acquired distinction. After a descriptive Part 1, Part 2 reviews why the innate?acquired distinction is under attack (...) in contemporary philosophy of biology. Three arguments are then presented to provide a limited and pragmatic defense of the distinction: an epistemic, a conceptual, and a historical argument. If interpreted in a certain manner, and if the pragmatic goals of prevention and treatment are taken into account, then the innate?acquired distinction can be a useful epistemic tool. It can help, first, to understand that genetic determination does not mean fatalism, and, second, to maintain a system of checks and balances in the continuing nature?nurture debates. (shrink)

Continuing Franz Boas' work to establish anthropology as an academic discipline in the US at the turn of the twentieth century, Alfred L. Kroeber re-defined culture as a phenomenon sui generis. To achieve this he asked geneticists to enter into a coalition against hereditarian thoughts prevalent at that time in the US. The goal was to create space for anthropology as a separate discipline within academia, distinct from other disciplines. To this end he crossed the boundary separating anthropology from biology (...) in order to secure the boundary. His notion of culture, closely bound to the concept of heredity, saw it as independent of biological heredity (culture as superorganic) but at the same time as a heredity of another sort. The paper intends to summarise the shifting boundaries of anthropology at the beginning of the twentieth century, and to present Kroeber?s ideas on culture, with a focus on how the changing landscape of concepts of heredity influenced his views. The historical case serves to illustrate two general conclusions: that the concept of culture played and plays different roles in explaining human existence; that genetics and the concept of Weismannian hard inheritance did not have an unambiguous unidirectional historical effect on the vogue for hereditarianism at that time; on the contrary, it helped to establish culture in Kroeber's sense, culture as independent of heredity. (shrink)

Darwin´s Erkenntnis über die Abstammung der Arten durch Mutation und Selektion sind in aller Munde, dass aber darüber im Detail noch viel Unklarheit herrscht, ist weniger bekannt. Es sind Fortschritte der Entwicklungsbiologie, die erst seit wenigen Jahren uns molekulare Erklärungsmuster an die Hand geben, mit denen die Entstehung neuer Arten besser verständlich wird. Es handelt sich um die Aufklärung der Wirkungsweise von Genen und ihren molekularen Produkten, die während der embryonalen Entwicklung von Tier und Mensch dafür sorgen, daß der Organismus (...) sich normal entwickelt. Treten Veränderungen (Mutationen) in einem dieser Mastergene auf, so wird dies zur Missbildung oder gar zum Absterben des betreffenden Embryos führen. Aber in seltenen Fällen kann so auch eine neue Tierart begründet werden. Gerade im Darwin-Jahr werden die Lehrbücher zur Evolutionsbiologie um ein wesentliches Kapitel erweitert. Es ist mit EvoDevo überschrieben und will damit ausdrücken, daß Evolutionary Theory ohne Developmental Biology keinen Sinn macht. Die bisherigen Lücken im Verständnis des Evolutionsgeschehens und die neue Sicht von EvoDevo wird im Folgenden dargestellt werden. (shrink)

Des branches entières des mathématiques sont fondées sur des liens posés entre les nombres et l’espace : mesure de longueurs, définition de repères et de coordonnées, projection des nombres complexes sur le plan… Si les nombres complexes, comme l’utilisation de repères, sont apparus relativement récemment (vers le XVIIe siècle), la mesure des longueurs est en revanche un procédé très ancien, qui remonte au moins au 3e ou 4e millénaire av. J-C. Loin d’être fortuits, ces liens entre les nombres et l’espace (...) reflèteraient une intuition fondamentale, universelle, façonnée au cours des millénaires par la sélection naturelle, et qui aurait servi de guide et d’inspiration aux mathématiciens au fil des siècles. (shrink)

The mapping of numbers onto space is fundamental to measurement and to mathematics. Is this mapping a cultural invention or a universal intuition shared by all humans regardless of culture and education? We probed number-space mappings in the Mundurucu, an Amazonian indigene group with a reduced numerical lexicon and little or no formal education. At all ages, the Mundurucu mapped symbolic and nonsymbolic numbers onto a logarithmic scale, whereas Western adults used linear mapping with small or symbolic numbers and logarithmic (...) mapping when numbers were presented nonsymbolically under conditions that discouraged counting. This indicates that the mapping of numbers onto space is a universal intuition and that this initial intuition of number is logarithmic. The concept of a linear number line appears to be a cultural invention that fails to develop in the absence of formal education. (shrink)

Bei der Suche nach dem rätselhaften Ursprung des Phänomens „Leben“ wird hier zunächst die zelluläre Ebene betrachtet. Im Grundaufbau zeigen alle Zellen viel Konstantes, aber gleichzeitig stellt jede Zelle ein einmaliges Individuum dar. Leben von Zellen gibt es nur als gegenseitiges Wechselspiel mit ihrer jeweiligen Umwelt. Das Genom (die Gesamtheit aller Gene) bleibt ab der Befruchtung in jeder Zelle eines Individuums konstant. Aber auch die Verwirklichung der Gene braucht eine „molekulare Umwelt“, besonders die vom Muttertier vorbereitete Umwelt im Zytoplasma des (...) Eies. Individualität eines Organismus (z.B. des Menschen) wird also nicht allein vom Genom festgelegt, sondern ist durch Entwicklungsprozesse bedingt (braucht Zeit!). „Leben“ kann (muß?) somit begriffen werden als ein wechselseitiges Kontinuum, welches alle Individuen, alle Spezies und alle Generationen miteinander und ihren Umwelten verbindet. Wie phylogenetisch betrachtet die allererste Zelle aus abiotischen Umständen entstehen konnte, wird hier nicht behandelt. Das Gesagte legt allerdings nahe, dass es nicht Gene waren, die sich eine belebte Welt erschufen, sondern bestimmte (Um-)Welten „erschufen“ sich Gene, die „lebenstauglich“ waren. (shrink)

Does geometry constitues a core set of intuitions present in all humans, regarless of their language or schooling ? We used two non verbal tests to probe the conceptual primitives of geometry in the Munduruku, an isolated Amazonian indigene group. Our results provide evidence for geometrical intuitions in the absence of schooling, experience with graphic symbols or maps, or a rich language of geometrical terms.

Is calculation possible without language? Or is the human ability for arithmetic dependent on the language faculty? To clarify the relation between language and arithmetic, we studied numerical cognition in speakers of Mundurukú, an Amazonian language with a very small lexicon of number words. Although the Mundurukú lack words for numbers beyond 5, they are able to compare and add large approximate numbers that are far beyond their naming range. However, they fail in exact arithmetic with numbers larger than 4 (...) or 5. Our results imply a distinction between a nonverbal system of number approximation and a language-based counting system for exact number and arithmetic. (shrink)

The concepts of reaction norms and phenotypic plasticity help us better understand what a biological trait is.

A critical examination of the dispute about the existence and significance of "plasticity genes.".

Developmental plasticity as the nexus between genetics and ecology.

An exploration of the nexus between ecology, evolutionary biology and molecular biology, via the concept of phenotypic plasticity.

Traditionally, Darwin has been grouped with the functionalists because natural selection (an adaptational mechanism) plays the prominent role in shaping organic form. In this paper, I sketch the dichotomy of functionalism versus structuralism and then argue that Darwin cannot be characterized adequately with this dichotomy. I argue that Darwin can incorporate both causal stories because he makes two important modifications to the traditional metaphysical presuppositions. I then offer some brief reflections on the import of Darwin's causal pluralism for the Philosophy (...) of Science. (shrink)

The concept of reaction norms plays a crucial role in connecting molecular and evolutionary biology.

How micro- and macroevolutionary evolutionary processes produce phenotypic change is without question one of the most intriguing and perplexing issues facing evolutionary biologists. We believe that roadblocks to progress lie A) in the underestimation of the role of the environment, and in particular, that of the interaction of genotypes with environmental factors, and B) in the continuing lack of incorporation of development into the evolutionary synthesis. We propose the integration of genetic, environmental and developmental perspectives on the evolution of the (...) phenotype in the form of the concept of the developmental reaction norm (DRN) The DRN represents the set of multivariate ontogenies that can be produced by a single genotype when it is exposed to environmental variation. It encompasses: 1) the processes that alter the phenotype throughout the ontogenetic trajectory, 2) the recognition that different aspects of the phenotype are (and must be) correlated and 3) the ability of a genotype to produce phenotypes in different environments. This perspective necessitates the explicit study of character expression during development, the evaluation of associations between pairs or groups of characters (e.g., multivariate allometries), and the exploration of reaction norms and phenotypic plasticity. We explicitly extend the concept of the DRN to encompass adjustments made in response to changes in the internal environment as well. Thus, ‘typical’ developmental sequences (e.g., cell fate determination) and plastic responses are simply manifestations of different scales of ‘environmental’ effects along a continuum. We present: (1) a brief conceptual review of three fundamental aspects of the generation and evolution of phenotypes: the changes in the trajectories describing growth and differentiation (ontogeny), the multivariate relationships among characters (allometry), and the effect of the environment (plasticity); (2) a discussion of how these components are merged in the concept of the developmental reaction norm; and (3) a reaction norm perspective of major determinants of phenotypes: epigenesis, selection and constraint. (shrink)

A discussion of plasticity genes and the genetic architecture of gene-environment interactions.

A response to Via about the existence (or not) and role of plasticity genes in evolution.