Joseph Bracken proposes to modify Whitehead’s tendency to see the comprehensive entities of everyday life as but aggregations of actual occasions. While there are resources in Polanyi’s notion of an emergent cosmos to counter Whitehead’s atomism and reductionism, Bracken’s use of Polanyi’s theory of a morphogenetic field as a corrective is argued to be only partially successful. Bracken must explain how morphogenetic fields evolve and arise. This step would require replacing Whiteheadian reductionism with a principle of ontological (...) parity that honors the reality of interaction between entities and the integration of their operational principles within basic ontological levels and setting forth principles of emergence to explain how these levels and fields arise. (shrink)

I discuss two uses of the concept of the morphogenetic field, a tool of the 19th century biology motivated by particular ontological views of the time, which has been re-emerging and increasingly relevant in explaining microbiological phenomena. I also consider the relation of these uses to the Central Dogma of modern biology as well as Modern Synthesis of Darwinism and genetics. An induced morphogenetic field is determined by a physical field, or it acquires a physical (...) field?s characteristics. Such a morphogenetic field presents only a weak challenge to the Central Dogma of Modern Synthesis by indirectly, albeit severely, constraining variability at the molecular level. I discuss explanations that introduce structural inheritance in ciliate protozoa, as well as the experimental evidence on which these arguments are based. The global cellular morphogenetic field is a unit of such inheritance. I discuss relevant cases of structural inheritance in ciliates that bring about internal cellular as well as functional changes and point out that DNA is absent in the cortex and that RNA controls neither intermediary nor the global level of the field. I go on to argue that utilizing knowledge of known physical fields may advance explanations and understanding of the morphogenetic field in ciliates as the unit of both development and inheritance. (shrink)

How biological form is generated remains one of the most fascinating but elusive challenges for science. Moreover, it is widely documented in contemporary literature that development is tightly coordinated. The idea that such development is governed by a coordinating field of force, the morphogenetic field, and its position in embryology research paradigms, is traced in this article. Empirical evidences for field phenomena are described, ranging from bioelectromagnetic effects, morphology, transplantation, regeneration, and other data. Applications of medical (...) potential including treatment of cancer, birth defects, and wound healing are highlighted. The article hypothesizes that distinct morphological forms may have distinct field parameters. Experimentally tractable field parameters may thus provide an exciting research program for probing morphogenesis and phylogenetic diversity. (shrink)

Embryonic and adult field do not exhibit the same properties because they are formed by cell populations whose activities cannot be compared in all respects. Dominant cells are not distributed in the same manner; the same mechanisms are not involved for remodelling of the field, especially after an amputation.In adult organisms, cell equilibrium is disturbed a first time by elimination of differentiated tissues which provokes dedifferentiation and proliferation, and a second time by healing, which restores cell equilibrium of (...) a distal end. Undifferentiated cells begin to differentiate immediately after their production and they reform the missing levels, following a sequence either basipetal or basifugal according to the place of their production . The differentiating regenerate temporarily exhibits embryonic field properties in various experimental conditions which suppress the dominance of the stump or supplies additional undifferentiated material. (shrink)

The purpose of this paper is to present a critique of the current view that reduces cancer to a cellular problem caused by specific gene mutations and to propose, instead, that such a problem might become more intelligible, if it is understood as a phenomenon that results from the breakdown of the morphological plan or Gestalt of the organism. Such and organism, in Aristotelian terms, is characterized for presenting a specific morphe or logos (form) and for having a telos (end) (...) to fulfill. A malignant tumor represents an entity separated from both the organic logos and the organic telos. According to the basic postulates of Semiophysics – a blend of Aristotelian physics and Catastrophe Theory developed by René Thom – an organism is a source (original) form individuated by a dominant pregnance that corresponds to its morphogenetic field. Here it is suggested that cancer in aged individuals might result from the progressive exhaustion of developmental constraints that regulate the process of ontogeny, that it is expected to go from the fertilized non-differentiated zygote to the mature fully developed organism, because there is no further point ahead in the developmental pathway past the reproductive age. Cancer in young individuals (before their reproductive maturity) may then be consequence of the premature derangement of such fundamental developmental constraints. In all cases the result is the loss of morphological coherence within the organism. Thus representing a conflict between an organized morphology (the organism) and a part of such a morphology that drifts towards an amorphous state (the tumor). (shrink)

Large sets of elements interacting locally and producing specific architectures reliably form a category that transcends the usual dividing line between biological and engineered systems. We propose to call them morphogenetically architected complex systems (MACS). While taking the emergence of properties seriously, the notion of MACS enables at the same time the design (or “meta-design”) of operational means that allow controlling and even, paradoxically, programming this emergence. To demonstrate our claim, we first show that among all the self-organized systems studied (...) in the field of Artificial Life, the specificity of MACS essentially lies in the close relation between their emergent properties and functional properties. Second, we argue that to be a MACS a system does not need to display more than weak emergent properties. Third, since the notion of weak emergence is based on the possibility of simulation, whether computational or mechanistic via machines, we see MACS as good candidates to help design artificial self-architected systems (such as robotic swarms) but also harness and redesign living ones (such as synthetic bacterial films). (shrink)

Large sets of elements interacting locally and producing specific architectures reliably form a category that transcends the usual dividing line between biological and engineered systems. We propose to call them morphogenetically architected complex systems. While taking the emergence of properties seriously, the notion of MACS enables at the same time the design of operational means that allow controlling and even, paradoxically, programming this emergence. To demonstrate our claim, we first show that among all the self-organized systems studied in the (...) class='Hi'>field of Artificial Life, the specificity of MACS essentially lies in the close relation between their emergent properties and functional properties. Second, we argue that to be a MACS a system does not need to display more than weak emergent properties. Third, since the notion of weak emergence is based on the possibility of simulation, whether computational or mechanistic via machines, we see MACS as good candidates to help design artificial self-architected systems but also harness and redesign living ones. (shrink)

While the vital contribution of feminist scholarship is acknowledged, it has been criticized for overly relying on the influence of society upon women’s lives. In this paper, I demonstrate the usefulness of also considering the influence of agency upon women’s lives, specifically agential reflexivity. Using the work and life histories of a group of Sri Lankan women, I use Margaret Archer’s morphogenetic approach to show how investigating reflexivity can provide greater insights into the subtleties associated with women’s agency in (...) relation to how they consciously organize their life journeys and react to oppression, demonstrate resistance and effect emancipation. My research reveals latent aspects of women’s agency within a postcolonial Third World social context, where an enduring patriarchal social system intersects with modernity and subjects women to complex social and occupational circumstances. This paper contributes to the field of women’s studies by showing how the morphogenetic approach can address the problem of conflationary theorizing within feminist scholarship. (shrink)

Embryonic development and ontogeny occupy whatis often depicted as the black box betweengenes – the genotype – and the features(structures, functions, behaviors) of organisms– the phenotype; the phenotype is not merelya one-to-one readout of the genotype. Thegenes home, context, and locus of operation isthe cell. Initially, in ontogeny, that cell isthe single-celled zygote. As developmentensues, multicellular assemblages of like cells(modules) progressively organized as germlayers, embryonic fields, anlage,condensations, or blastemata, enable genes toplay their roles in development and evolution.As modules, condensations are (...) fundamentaldevelopmental and selectable units ofmorphology (morphogenetic units) that mediateinteractions between genotype and phenotype viaevolutionary developmental mechanisms. In ahierarchy of emergent processes, gene networksand gene cascades (genetic modules) link thegenotype with morphogenetic units such ascondensations, while epigenetic processes suchas embryonic inductions, tissue interactionsand functional integration, link morphogeneticunits to the phenotype. To support theseconclusions I distinguish units of heredityfrom units of transmission and discussepigenetic inheritance by tracing the historyof relationship between embryology andevolution, especially the role(s) assigned tocells or to cellular components in generatingtheories of morphological change in evolution.The concept of cells as modular morphogeneticunits is modeled and illustrated using themammalian dentary bone. (shrink)

Form follows function, but it does not follow from function. Form is not derivable from the latter. To realize a desired technical function, a form must first be found that is able to realize it at all. Secondly, the question arises as to whether an envisaged form realizes the function in an appropriate way. Functions are multiply realizable—various different forms can bear the very same function. One needs to find a form of a technical artifact that realizes an envisaged function (...) sufficiently efficient, robust, or whatever criteria might be imposed. This paper scrutinizes biomimetics as one way to find a good solution to the realization problem. Drawing on an approach from the philosophy of simulations, it reconstructs the biomimetic relation as being mediated by a theoretical model. It is shown that the robustness of the functioning system is usually reached in different ways in biological and in technological systems, which explains differences in morphogenetic mechanisms or principles found in these fields. This reconstruction helps to understand problems with robustness in synthetic biology that occur when technical design principles are implemented in a biological system. The mimetic relation between the biological and the technical realm is found to be asymmetric. (shrink)

Bracken synthesizes Polanyi’s notion of morphogentic field and Whitehead’s notion of societies of actual occasions. These comments emphasize the implications of the metaphors involved in these notions. The rnetaphor of plants growing in afield lies beyond the concept of a morphogenetic field, and the metaphor of a society of interacting persons lies behind the concept of a society of actual occasions. I suggest that one of the implications of this metaphor is that there is not, as Bracken (...) argues, a problem of continuity in Whitehead’s metaphysics of events. (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)

Bracken synthesizes Polanyi’s notion of morphogentic field and Whitehead’s notion of societies of actual occasions. These comments emphasize the implications of the metaphors involved in these notions. The rnetaphor of plants growing in afield lies beyond the concept of a morphogenetic field, and the metaphor of a society of interacting persons lies behind the concept of a society of actual occasions. I suggest that one of the implications of this metaphor is that there is not, as Bracken (...) argues, a problem of continuity in Whitehead’s metaphysics of events. (shrink)

Classical ethology, with its emphasis on separability of parts, has largely failed to do justice to the wholeness of the individual animal, to the integrity of group behaviour and to the continuity between observable behaviour and consciousness. Field theory has potentialities to do better, as illustrated in this paper with reference to morphogenetic and behavioural fields. A behavioural domain is delineated — playlike behaviour — where field theory is particularly relevant. It is shown that the concept of (...) symmetry can suggest new questions as well as explain some generally known phenomena of group behaviour. New interpretations of displacement activities and of etho-ecological adaptations are offered, both of which involve the whole individual animal. (shrink)

Description courte (Électre, 2019) : Une étude d'un des principaux axes de réflexion du philosophe des sciences et de la nature Raymond Ruyer (1902-1987). À la lumière des découvertes de l'embryogenèse et en s'appuyant par ailleurs sur la théorie de l'information, il proposa une interprétation des concepts unificateurs de la cybernétique mécaniste. -/- Short Descriptor (Electre 2019): A study of one of the main axes of reflection of the French philosopher of science and of nature Raymond Ruyer (1902-1987). Relying on (...) the discoveries about embryogenesis, and also with the use of information theory, Ruyer proposed an interpretation of the main unifying concepts of mechanistic cybernetics. -/- Cet ouvrage propose une étude fouillée d'un des principaux axes de réflexion du philosophe des sciences et de la nature français Raymond Ruyer (1902–1987) : la cybernétique. Après avoir proposé une philosophie structuraliste, Ruyer la modifia à la lumière des découvertes de l'embryogenèse, puis il proposa une interprétation des concepts unificateurs de la cybernétique mécaniste. Réfléchissant sur cette dernière et sur la théorie de l'information, en particulier sur l'origine de l'information, il défendit que cette cybernétique n'était qu'une lecture inversée de la vraie cybernétique, qui nous donnerait de lire dans l'expérience même les traces du pouvoir morphogénétique, appréhendé comme un champ axiologique. Dans un texte résumant son propre parcours, Ruyer affirma finalement que la critique de la théorie de l'information « peut donner […] l'espoir d'aboutir à quelque chose comme une nouvelle théologie. » Les idées directrices de Ruyer sont tout particulièrement contextualisées ici à partir de la question du développement des formes en biologie, et de celles de la génétique, de la genèse stochastique de l'ordre, et de l'identification mentale ou physique de l'information. Il se termine en départageant ce qui est théologique et axiologique dans ce projet de métaphysique qui, bien que resté inachevé, n'en représente pas moins le plus impressionnant conçu en France au siècle dernier. – This book offers an in-depth study of one of the main axes in the reflection of French philosopher of science and nature Raymond Ruyer. In a text summarising his own development, Ruyer stated about the philosophical critique of information theory that it "is what can give the most long-lasting hope of getting to something like a new theology." After propounding a structuralist philosophy, and distinguishing between form and structure, to then modify it in the light of discoveries in embryogenesis, Ruyer offered a re-evaluation of the unifying concepts of mechanistic cybernetics. Thinking about it and about information theory, he defended the idea that this cybernetics was in reality an inverted reading of the real one, which would allow us to read in experience itself traces of the morphogenetic power, apprehended as the axiological field. On some transversal points, the development of forms in biology and genetics, the stochastic genesis of order, the identification of information with either psychological and mental, or physical reality, behaviour, and the access to meaning, this work exposes the main ideas of Ruyer while situating them in the context of the breadth of others' contributions. It ends by determining what is theological and axiological in this project for a metaphysics which, although unfinished, is nevertheless the most impressive effort done in France in the last century. – Available on i6doc dot com (ISBN 978-2-930517-56-8 ; pdf 978-2-930517-57-5). (shrink)

Morphogenetic fields of thought, flux and transformation, energy and light are the manifestations that inform a new sensibility for creating realities and exploring the world. We are seeing the emergence of a new moistmedia culture and the possibilities of a syncretic art that combines aspects of a vast transdisciplinary field. Historically, syncretism has destabilized political and religious orthodoxies, reconciling and harmonizing formerly discrete antagonists; its etymology derives from the coming together of opposed tribes to resist a common enemy. (...) In contemporary culture, the enemy is habit - the uncritical repetition of behaviours, perceptions, categories and values. Just as cybernetics analogizes differences between systems, so syncretism finds likeness between unlike things. If cybernetics underlies the technology of new media art, syncretism informs the psyche. In the context of telematics, it is a matter of heuristics and heteronymia. The digital moment in art is passing as it approaches the status of orthodoxy; the period of discovery through extreme speculation, invention and untrammelled creativity is in danger of giving way to academicism and commercialization, whether in cyberspace, on the Web or through the mobile. Art's twentieth-century preoccupation with the body is giving way to the technoetic exploration of new territories of mind. This may involve revisiting the pathways to personal transformation and transcendence of older cultures, where the syncretism of knowledge and beliefs, as for example in Brazil, is explicit. Art needs to adopt syncretic strategies to embrace emerging models of mind and matter, cyberception, living process and computational systems, moist-media, quantum reality, the nanofield, and ecological, social and spiritual issues. This may lead to significant changes in the way we regard our own identity, our relationship to others, the nature of memory, the exploration of consciousness, and the phenomenology of time and space. (shrink)

본 논고는 대한민국 사회를 관통하고 있는 불법촬영물이라는 특정 포획물을 기반으로 분포하고 있는 ‘관음충’에 대한 형태발생학적인(morphogenetic) 고찰이다. 형태발생학적 고찰이란 대한민국의 사회문화적 환경 안에서 디지털 성범죄 시스템을 추동시키는 ‘관음충’이라는 특정 군집구성체(population)가 어떠한 젠더와 조건을 중심으로 발생과 생장, 증식을 거듭하는지를 추적함을 의미한다. 필자는 한남유충-관음충-한남충이라는 용어가 배태하고 있는 곤충 군집체의 형태발생학적 착상(conception, idea)을 적극적으로 활용하여 본 논의의 배경(background)으로 삼고자 한다. 그리하여 한남충을 알-유충-성충의 단계에서 탈피와 성장을 거듭하지만 형태상으로 비슷한 상태를 유지하는 ‘불완전변태(homomorphism)’의 모델로 분석하고자 하는 것이다. 또한 ‘한남유충’에서 ‘한남충’으로의 변태(metamorphosis) 과정의 추이가 ‘관음충’의 지수(factor)를 (...) 통해 구체적으로 어떠한 방식으로 단계적으로 진화 가능한지를 첨예하게 드러내고자 한다. 이를 위해 필자는 미국의 신물질주의(New materialism) 이론의 선두주자이자 들뢰즈의 현대적 계승자인 마뉴엘 데란다(Manuel De Landa)의 이론적 틀을 창의적으로 재해석함으로써 관음충 군집체의 발생과 진화과정, 그것의 잠재적 궤적 방향과 현실적 양태에 대한 비판적 분석을 시도할 것이다. 그러하기에 첫째, 데란다가 제시한 ‘군집구성체적 사고(population thinking)’ 틀을 통해 한국에서 태어난 남아가 어떻게 ‘관음충’으로 집단적으로 생장, 진화하는가를 분석하고자 사회문화적으로 다양한 자가복제 기제들(replicators)을 들여다보도록 하겠다. 둘째, ‘강렬도의 사고(intensive thinking)’ 틀을 통해 관음충의 형태발생학적 변화 과정을 ‘영토화(territorialisation)와 코드화(coding)’라는 두 가지 기준척도를 통해 각각의 변이국면의 주요 특이점들을 파악하고 고찰할 것이다. 셋째, ‘위상학적 사고(Topological thinking)’ 틀을 통해 가부장제 자본주의 사회지평 내 관음충 군집체가 주파할 잠재적 궤도 방향과 메커니즘을 분석, 고찰하고 대한민국 사회가 이 궤도로부터 어떻게 이탈 가능할지를 페미니즘적으로 사유하도록 하겠다. (shrink)

A topological inevitability of early developmental events through the use of classical topological concepts is discussed. Topological dynamics of forms and maps in embryo development are presented. Forms of a developing organism such as cell sets and closed surfaces are topological objects. Maps (or mathematical functions) are additional topological constructions in these objects and include polarization, singularities and curvature. Topological visualization allows us to analyze relationships that link local morphogenetic processes and integral developmental structures and also to find stable (...) spatio-temporal topological characteristics that are invariant for a taxonomic group. The application of topological principles reveals a topological imperative: certain topological rules define and direct embryogenesis. A topological stability of embryonic morphogenesis is proposed and a topological scenario of developmental and evolutionary transformations is presented. (shrink)

Is it possible to explain and predict the development of living things? What is development? Articulate answers to these seemingly innocuous questions are far from straightforward. To date, no systematic, targeted effort has been made to construct a unifying theory of development. This novel work offers a unique exploration of the foundations of ontogeny by asking how the development of living things should be understood. It explores the key concepts of developmental biology, asks whether general principles of development can be (...) discovered, and examines the role of models and theories.The two editors have assembled a team of leading contributors who are representative of the scientific and philosophical community within which a diversity of thoughts are growing, and out of which a theory of development may eventually emerge. They analyse a wealth of approaches to concepts, models and theories of development, such as gene regulatory networks, accounts based on systems biology and on physics of soft matter, the different articulations of evolution and development, symbiont-induced development, as well as the widely discussed concepts of positional information and morphogenetic field, the idea of a. (shrink)

Much of the current research in regenerative medicine concentrates on stem-cell therapy that exploits the regenerative capacities of stem cells when injected into different types of human tissues. Although new therapeutic paths have been opened up by induced pluripotent cells and human mesenchymal cells, the rate of success is still low and mainly due to the difficulties of managing cell proliferation and differentiation, giving rise to non-controlled stem cell differentiation that ultimately leads to cancer. Despite being still far from becoming (...) a reality, these studies highlight the role of physical and biological constraints (e.g., cues and morphogenetic fields) placed by tissue microenvironment on stem cell fate. This asks for a clarification of the coupling of stem cells and microenvironmental factors in regenerative medicine. We argue that extracellular matrix and stem cells have a causal reciprocal and asymmetric relationship in that the 3D organization and composition of the extracellular matrix establish a spatial, temporal, and mechanical control over the fate of stem cells, which enable them to interact and control (as well as be controlled by) the cellular components and soluble factors of microenvironment. Such an account clarifies the notions of stemness and stem cell regeneration consistently with that of microenvironment. (shrink)

Despite the triumphant rhetoric of mechanistic materialism, current biology has no shortage of unsolved fundamental problems. In 1981, seeking a way forward, Rupert Sheldrake proposed the hypothesis of “formative causation” as a unifying organizing principle of life. Expanding the concept of morphogenetic fields, Sheldrake posited a spatio‐temporal connection termed “morphic resonance” whereby the more often a self‐organizing process takes place, the easier it will be for it to take place in the future. After initial acclaim, his project was quickly (...) met with dogmatic skepticism, dismissed as scientific heresy, and ultimately ignored. Forty years later, the experimental implications of his ideas remain largely untested. Visionary or not, Sheldrake's case illustrates the conceptual resistance of the scientific enterprise to revise its own deepest theoretical commitments. Beyond career‐building selection pressures, young researchers need to be presented with the major questions in their field and encouraged to entertain radically alternative points of view. Science is what scientists make of it. (shrink)

While many different mechanisms contribute to the generation of spatial order in biological development, the formation of morphogenetic fields which in turn direct cell responses giving rise to pattern and form are of major importance and essential for embryogenesis and regeneration. Most likely the fields represent concentration patterns of substances produced by molecular kinetics. Short range autocatalytic activation in conjunction with longer range “lateral” inhibition or depletion effects is capable of generating such patterns (Gierer and Meinhardt, 1972). Non-linear reactions (...) are required, and mathematical criteria were derived to design molecular models capable of pattern generation. The classical embryological feature of proportion regulation can be incorporated into the models. The conditions are mathematically necessary for the simplest two-factor case, and are likely to be a fair approximation in multi-component systems in which activation and inhibition are systems parameters subsuming the action of several agents. Gradients, symmetric and periodic patterns, in one or two dimensions, stable or pulsing in time, can be generated on this basis. Our basic concept of autocatalysis in conjunction with lateral inhibition accounts for self-regulatory biological features, including the reproducible formation of structures from near-uniform initial conditions as required by the logic of the generation cycle. Real tissue form, for instance that of budding Hydra, may often be traced back to local curvature arising within an initially relatively flat cell sheet, the position of evagination being determined by morphogenetic fields. Shell theory developed for architecture may also be applied to such biological processes. (shrink)

C.H. Waddington’s concepts of ‘chreods’ (canalized paths of development) and ‘homeorhesis’ (the tendency to return to a path), each associated with ‘morphogenetic fields’, were conceived by him as a contribution to complexity theory. Subsequent developments in complexity theory have largely ignored Waddington’s work and efforts to advance it. Waddington explained the development of the concept of chreod as the influence on his work of Alfred North Whitehead’s process philosophy, notably, the concept of concrescence as a self-causing process. Processes were (...) recognized as having their own dynamics, rather than being explicable through their components or external agents. Whitehead recognized the tendency to think only in terms of such ‘substances’ as a bias of European thought, claiming in his own philosophy ‘to approximate more to some strains of Indian, or Chinese, thought, than to western Asiatic, or European, thought.’ Significantly, the theoretical biologist who comes closest to advancing Waddington’s research program, also marginalized, is Mae-Wan Ho. Noting this bias, and embracing Whitehead’s and Waddington’s efforts to free biology from assumptions dominating Western thought to advance an ontology of creative causal processes, I will show how later developments of complexity theory, most importantly, Goodwin’s work on oscillations, temporality and morphogenesis, Vitiello’s dissipative quantum brain dynamics, Salthe’s work on hierarchy theory, biosemiotics inspired by Peirce and von Uexküll, Robert Rosen’s work on anticipatory systems, together with category theory and biomathics, can augment while being augmented by Waddington’s work, while further advancing Mae-Wan Ho’s radical research program with its quest to understand the reality of consciousness. (shrink)

Despite the extensive literature describing the somatic genetic alterations in cancer cells, the precise origins of cancer cells remain controversial. In this article, I suggest that the etiology of cancer and the generation of genetic instability in cancer cells should be considered in the light of recent findings on both the stochastic nature of gene expression and its regulation at tissue level. By postulating that gene expression is intrinsically probabilistic and that stabilization of gene expression arises by cellular interactions in (...) “morphogenetic fields”, development and cellular differentiation can be rethought in an evolutionary perspective. In particular, this article proposes that disruptions of cellular interactions are the initial source of abnormal gene expression in cancer cells. Consequently, cancer phenotypes such as genetic and epigenetic instabilities, and also the presence of cells with stem cell‐like properties, may result from inaccurate and aberrant patterns of gene expression generated by microenvironmental alterations. Finally, the therapeutic implications of this view are discussed. BioEssays 27:1277–1285, 2005. © 2005 Wiley Periodicals, Inc. (shrink)

Experimental evidence strongly supports the view that the subdivision of organ anlagen into smaller structural units is an autonomous process. Dalcq &Pasteels' hypothesis which says that the boundaries between the different areas into which a morphogenetic field differentiates are determined by “Threshold values” in the “potential” of the field in question, is inconsistent with our present knowledge of biochemical reaction systems. Threshold values may only be used indescribing the spatial differentiation of a morphogenetic field. It (...) is suggested that the latter concept be replaced by the concept of “optimal values” in the intensity of a morphogenetic field-specific for the various chemo-differentiations characterizing the different regions into which a morphogenetic field will split up-and that each optimal value isdeterminative for the appearance of one particular differentiation within the morphogenetic field, each differentiation being formed within a certain range of intensity of the field. On the basis of the hypothesis formulated above a “virginal” morphogenetic field will necessarily differentiate into a number of smaller fields of second order, which in their turn will split up into fields of third order, etc. ” Pattern formation” may be defined as the differentiation of a morphogenetic field into an increasing number of smaller fields of higher order of qualitative different chemical and structural composition. Since differentiation of a morphogenetic field proceeds autonomously, the capacity for pattern formation is an intrinsic property of a morphogenetic field. In the light of these considerations it is suggested that a morphogenetic field action is responsible for the first differentiation of the developing embryo into regions with predominantly ectodermal, mesodermal or endodermal differentiation tendencies. The present knowledge about the characteristic pattern formation taking place in the axial mesoderm as well as in the overlying neural plate seems to be in good agreement with the implications of the present morphogenetic field concept. It is emphasized, however, that if the present morphogenetic field concept cannot be characterized further biochemically and biophysically, it will have to be replaced by another concept which can be defined more sharply and is more easily accessible to experimental analysis. Les preuves expérimentales confirment que la subdivision des ébauches des organes en unités structurelles plus petites est un processus autonome. L'hypothèse deDalcq &Pasteels disant que les bornes entre les différents domaines formées par la différenciation d'un champ morphogénétique sont déterminées par des „valeurs seuil” dans le „potentiel” du champ en question, n'est pas en harmonie avec notre connaissance actuelle des systèmes biochimiques. Des “valeurs seuil” ne peuvent être employés qu'en décrivant la différenciation spatiale d'un champ morphogénétique. On prend en considération de remplacer le concept des “valeurs seuil” par le concept des “valeurs optimales” dans l'intensité d'un champ morphogénétique. Ce seraient les valeurs spécifiques aux différenciations chimiques diverses qui caractérisent les différents domaines dans lesquels un champ morphogénétique se différencie. En outre, chaque valeur optimale serait déterminative à la formation d'une différenciation spéciale dans le champ morphogénétique, chaque différentiation se formant dans un certain trajet de l'intensité du champ. Par suite de l'hypothèse formulée ci-dessus un champ morphogénétique “virginal” va nécessairement se différencier en un nombre de champs plus petits de deuxième ordre, qui à leur tour se divisent en champs d'ordre troisième, etc. ... La régionalisation peut être définie comme la différenciation d'un champ morphogénétique dans un nombre de plus en plus élevé de champs plus petits d'ordre supérieur de composition chimique et structurelle qualitativement différente. Parce que la différenciation d'un champ morphogénétique se produit de façon autonome, le pouvoir de régionalisation est une propriété intrinsique d'un champ morphogénétique. Ces considérations nous mènent à proposer que l'action d'un champ morphogénétique est responsable de la première différenciation de l'embryon en régions qui possèdent des tendences de différenciation principalement ectodermiques, mésodermiques, ou bien endodermiques. La connaissance actuelle concernant la régionalisation caractéristique qui se produit dans le mésoderme axial ainsi que dans la plaque neurale superposée paraît se conformer aux conséquences du concept de champ morphogénétique. Cependant on souligne le fait que dans le cas òu le concept actuel du champ morphogénétique ne pourra pas être plus amplement caractérisé de façon biochimique et biophysique, il faudra le remplacer par un autre concept qui puit être défini plus nettement et qui est mieux accessible à l'analyse expérimentale. Die Auffassung, dass die Aufteilung von Organanlagen in kleineren Struktureinheiten ein selbständiger Prozess ist, findet Bestätigung in den experimentellen Ergebnissen. Die Hypothese vonDalcq &Pasteels , dass die Grenzen zwischen den unterschiedenen Gebieten, in denen ein morphogenetisches Feld sich differenziert, durch “Schwellenwerte” im “Potential” des genannten Feldes bestimmt werden, ist unvereinbar mit unserem heutigen Wissen über biochemischen Reaktionssystemen. Der Gebrauch des Begriffs “Schwellenwert” ist nur gestattet bei der Beschreibung der räumlichen Differenzierung eines morphogenetischen Feldes. Statt dieses Begriffs wird der Begriff “Optimaler Wert” vorgeschlagen; Werte also in der Intensität eines morphogenetischen Feldes, optimal und spezifisch für die verschiedene Chemodifferenzierungen, welche die Gebiete kennzeichnen, in denen ein morphogenetisches Feld sich differenzieren wird. Jeder optimaler Wert soll dann das Erscheinen einer bestimmten Differenzierung innerhalb des morphogenetischen Feldes veranlassen, welche Differenzierung sich bildet innerhalb eines bestimmten Bereichs der Feldintensität. Auf Grund der obigen Hypothese wird ein “virginelles” morphogenetisches Feld zwangsläufig sich differenzieren in eine Anzahl kleinerer Feldern zweiten Grades; diese in Felder dritten Grades, usw. Musterbildung könnte definiert werden als die Differenzierung eines morphogenetischen Feldes in eine zunehmende Anzahl kleinerer Felder höheren Grades von qualitativ verschiedener chemischen und strukturellen Zusammensetzung, Weil diese Differenzierung autonom vor sich geht, ist das Vermögen zur Musterbildung eine innewohnende Eigenschaft eines morphogenetischen Feldes. Im Lichte dieser Betrachtungen ist es naheliegend anzunehmen dass eine morphogenetische Feldwirkung verantwortlich ist für die erste Differenzierung des sich entwickelnden Embryos in Gebiete überwiegend ektodermalen, mesodermalen oder entodermalen Differenzierungstendenzen. Die heutigen Kenntnisse über die charakteristische Musterbildung im axialen Teil des Mesoderms und in der überliegenden Neuralplatte scheinen in guter Übereinstimmung zu sein mit den des morphogenetischen Feldbegriffs. Dennoch wird benachdruckt, dass, falls das gegenwärtige morphogenetische Feldbegriff nicht weiter biochemisch und biophysisch gekennzeichnet werden kann, anstatt dessen ein anderer Begriff entwickelt werden muß, der schärfer definiert werden kann und besser zugänglich ist für experimentelle Analyse. (shrink)

Experimental evidence strongly supports the view that the subdivision of organ anlagen into smaller structural units is an autonomous process. Dalcq &Pasteels' hypothesis which says that the boundaries between the different areas into which a morphogenetic field differentiates are determined by “Threshold values” in the “potential” of the field in question, is inconsistent with our present knowledge of biochemical reaction systems. Threshold values may only be used indescribing the spatial differentiation of a morphogenetic field. It (...) is suggested that the latter concept be replaced by the concept of “optimal values” in the intensity of a morphogenetic field-specific for the various chemo-differentiations characterizing the different regions into which a morphogenetic field will split up-and that each optimal value isdeterminative for the appearance of one particular differentiation within the morphogenetic field, each differentiation being formed within a certain range of intensity of the field. On the basis of the hypothesis formulated above a “virginal” morphogenetic field will necessarily differentiate into a number of smaller fields of second order, which in their turn will split up into fields of third order, etc. ” Pattern formation” may be defined as the differentiation of a morphogenetic field into an increasing number of smaller fields of higher order of qualitative different chemical and structural composition. Since differentiation of a morphogenetic field proceeds autonomously, the capacity for pattern formation is an intrinsic property of a morphogenetic field. In the light of these considerations it is suggested that a morphogenetic field action is responsible for the first differentiation of the developing embryo into regions with predominantly ectodermal, mesodermal or endodermal differentiation tendencies. The present knowledge about the characteristic pattern formation taking place in the axial mesoderm as well as in the overlying neural plate seems to be in good agreement with the implications of the present morphogenetic field concept. It is emphasized, however, that if the present morphogenetic field concept cannot be characterized further biochemically and biophysically, it will have to be replaced by another concept which can be defined more sharply and is more easily accessible to experimental analysis. Les preuves expérimentales confirment que la subdivision des ébauches des organes en unités structurelles plus petites est un processus autonome. L'hypothèse deDalcq &Pasteels disant que les bornes entre les différents domaines formées par la différenciation d'un champ morphogénétique sont déterminées par des „valeurs seuil” dans le „potentiel” du champ en question, n'est pas en harmonie avec notre connaissance actuelle des systèmes biochimiques. Des “valeurs seuil” ne peuvent être employés qu'en décrivant la différenciation spatiale d'un champ morphogénétique. On prend en considération de remplacer le concept des “valeurs seuil” par le concept des “valeurs optimales” dans l'intensité d'un champ morphogénétique. Ce seraient les valeurs spécifiques aux différenciations chimiques diverses qui caractérisent les différents domaines dans lesquels un champ morphogénétique se différencie. En outre, chaque valeur optimale serait déterminative à la formation d'une différenciation spéciale dans le champ morphogénétique, chaque différentiation se formant dans un certain trajet de l'intensité du champ. Par suite de l'hypothèse formulée ci-dessus un champ morphogénétique “virginal” va nécessairement se différencier en un nombre de champs plus petits de deuxième ordre, qui à leur tour se divisent en champs d'ordre troisième, etc.... La régionalisation peut être définie comme la différenciation d'un champ morphogénétique dans un nombre de plus en plus élevé de champs plus petits d'ordre supérieur de composition chimique et structurelle qualitativement différente. Parce que la différenciation d'un champ morphogénétique se produit de façon autonome, le pouvoir de régionalisation est une propriété intrinsique d'un champ morphogénétique. Ces considérations nous mènent à proposer que l'action d'un champ morphogénétique est responsable de la première différenciation de l'embryon en régions qui possèdent des tendences de différenciation principalement ectodermiques, mésodermiques, ou bien endodermiques. La connaissance actuelle concernant la régionalisation caractéristique qui se produit dans le mésoderme axial ainsi que dans la plaque neurale superposée paraît se conformer aux conséquences du concept de champ morphogénétique. Cependant on souligne le fait que dans le cas òu le concept actuel du champ morphogénétique ne pourra pas être plus amplement caractérisé de façon biochimique et biophysique, il faudra le remplacer par un autre concept qui puit être défini plus nettement et qui est mieux accessible à l'analyse expérimentale. Die Auffassung, dass die Aufteilung von Organanlagen in kleineren Struktureinheiten ein selbständiger Prozess ist, findet Bestätigung in den experimentellen Ergebnissen. Die Hypothese vonDalcq &Pasteels, dass die Grenzen zwischen den unterschiedenen Gebieten, in denen ein morphogenetisches Feld sich differenziert, durch “Schwellenwerte” im “Potential” des genannten Feldes bestimmt werden, ist unvereinbar mit unserem heutigen Wissen über biochemischen Reaktionssystemen. Der Gebrauch des Begriffs “Schwellenwert” ist nur gestattet bei der Beschreibung der räumlichen Differenzierung eines morphogenetischen Feldes. Statt dieses Begriffs wird der Begriff “Optimaler Wert” vorgeschlagen; Werte also in der Intensität eines morphogenetischen Feldes, optimal und spezifisch für die verschiedene Chemodifferenzierungen, welche die Gebiete kennzeichnen, in denen ein morphogenetisches Feld sich differenzieren wird. Jeder optimaler Wert soll dann das Erscheinen einer bestimmten Differenzierung innerhalb des morphogenetischen Feldes veranlassen, welche Differenzierung sich bildet innerhalb eines bestimmten Bereichs der Feldintensität. Auf Grund der obigen Hypothese wird ein “virginelles” morphogenetisches Feld zwangsläufig sich differenzieren in eine Anzahl kleinerer Feldern zweiten Grades; diese in Felder dritten Grades, usw. Musterbildung könnte definiert werden als die Differenzierung eines morphogenetischen Feldes in eine zunehmende Anzahl kleinerer Felder höheren Grades von qualitativ verschiedener chemischen und strukturellen Zusammensetzung, Weil diese Differenzierung autonom vor sich geht, ist das Vermögen zur Musterbildung eine innewohnende Eigenschaft eines morphogenetischen Feldes. Im Lichte dieser Betrachtungen ist es naheliegend anzunehmen dass eine morphogenetische Feldwirkung verantwortlich ist für die erste Differenzierung des sich entwickelnden Embryos in Gebiete überwiegend ektodermalen, mesodermalen oder entodermalen Differenzierungstendenzen. Die heutigen Kenntnisse über die charakteristische Musterbildung im axialen Teil des Mesoderms und in der überliegenden Neuralplatte scheinen in guter Übereinstimmung zu sein mit den des morphogenetischen Feldbegriffs. Dennoch wird benachdruckt, dass, falls das gegenwärtige morphogenetische Feldbegriff nicht weiter biochemisch und biophysisch gekennzeichnet werden kann, anstatt dessen ein anderer Begriff entwickelt werden muß, der schärfer definiert werden kann und besser zugänglich ist für experimentelle Analyse. (shrink)

Experimental evidence strongly supports the view that the subdivision of organ anlagen into smaller structural units is an autonomous process. Dalcq &Pasteels' hypothesis which says that the boundaries between the different areas into which a morphogenetic field differentiates are determined by “Threshold values” in the “potential” of the field in question, is inconsistent with our present knowledge of biochemical reaction systems. Threshold values may only be used indescribing the spatial differentiation of a morphogenetic field. It (...) is suggested that the latter concept be replaced by the concept of “optimal values” in the intensity of a morphogenetic field-specific for the various chemo-differentiations characterizing the different regions into which a morphogenetic field will split up-and that each optimal value isdeterminative for the appearance of one particular differentiation within the morphogenetic field, each differentiation being formed within a certain range of intensity of the field. On the basis of the hypothesis formulated above a “virginal” morphogenetic field will necessarily differentiate into a number of smaller fields of second order, which in their turn will split up into fields of third order, etc. ” Pattern formation” may be defined as the differentiation of a morphogenetic field into an increasing number of smaller fields of higher order of qualitative different chemical and structural composition. Since differentiation of a morphogenetic field proceeds autonomously, the capacity for pattern formation is an intrinsic property of a morphogenetic field. In the light of these considerations it is suggested that a morphogenetic field action is responsible for the first differentiation of the developing embryo into regions with predominantly ectodermal, mesodermal or endodermal differentiation tendencies. The present knowledge about the characteristic pattern formation taking place in the axial mesoderm as well as in the overlying neural plate seems to be in good agreement with the implications of the present morphogenetic field concept. It is emphasized, however, that if the present morphogenetic field concept cannot be characterized further biochemically and biophysically, it will have to be replaced by another concept which can be defined more sharply and is more easily accessible to experimental analysis. Les preuves expérimentales confirment que la subdivision des ébauches des organes en unités structurelles plus petites est un processus autonome. L'hypothèse deDalcq &Pasteels disant que les bornes entre les différents domaines formées par la différenciation d'un champ morphogénétique sont déterminées par des „valeurs seuil” dans le „potentiel” du champ en question, n'est pas en harmonie avec notre connaissance actuelle des systèmes biochimiques. Des “valeurs seuil” ne peuvent être employés qu'en décrivant la différenciation spatiale d'un champ morphogénétique. On prend en considération de remplacer le concept des “valeurs seuil” par le concept des “valeurs optimales” dans l'intensité d'un champ morphogénétique. Ce seraient les valeurs spécifiques aux différenciations chimiques diverses qui caractérisent les différents domaines dans lesquels un champ morphogénétique se différencie. En outre, chaque valeur optimale serait déterminative à la formation d'une différenciation spéciale dans le champ morphogénétique, chaque différentiation se formant dans un certain trajet de l'intensité du champ. Par suite de l'hypothèse formulée ci-dessus un champ morphogénétique “virginal” va nécessairement se différencier en un nombre de champs plus petits de deuxième ordre, qui à leur tour se divisent en champs d'ordre troisième, etc. ... La régionalisation peut être définie comme la différenciation d'un champ morphogénétique dans un nombre de plus en plus élevé de champs plus petits d'ordre supérieur de composition chimique et structurelle qualitativement différente. Parce que la différenciation d'un champ morphogénétique se produit de façon autonome, le pouvoir de régionalisation est une propriété intrinsique d'un champ morphogénétique. Ces considérations nous mènent à proposer que l'action d'un champ morphogénétique est responsable de la première différenciation de l'embryon en régions qui possèdent des tendences de différenciation principalement ectodermiques, mésodermiques, ou bien endodermiques. La connaissance actuelle concernant la régionalisation caractéristique qui se produit dans le mésoderme axial ainsi que dans la plaque neurale superposée paraît se conformer aux conséquences du concept de champ morphogénétique. Cependant on souligne le fait que dans le cas òu le concept actuel du champ morphogénétique ne pourra pas être plus amplement caractérisé de façon biochimique et biophysique, il faudra le remplacer par un autre concept qui puit être défini plus nettement et qui est mieux accessible à l'analyse expérimentale. Die Auffassung, dass die Aufteilung von Organanlagen in kleineren Struktureinheiten ein selbständiger Prozess ist, findet Bestätigung in den experimentellen Ergebnissen. Die Hypothese vonDalcq &Pasteels , dass die Grenzen zwischen den unterschiedenen Gebieten, in denen ein morphogenetisches Feld sich differenziert, durch “Schwellenwerte” im “Potential” des genannten Feldes bestimmt werden, ist unvereinbar mit unserem heutigen Wissen über biochemischen Reaktionssystemen. Der Gebrauch des Begriffs “Schwellenwert” ist nur gestattet bei der Beschreibung der räumlichen Differenzierung eines morphogenetischen Feldes. Statt dieses Begriffs wird der Begriff “Optimaler Wert” vorgeschlagen; Werte also in der Intensität eines morphogenetischen Feldes, optimal und spezifisch für die verschiedene Chemodifferenzierungen, welche die Gebiete kennzeichnen, in denen ein morphogenetisches Feld sich differenzieren wird. Jeder optimaler Wert soll dann das Erscheinen einer bestimmten Differenzierung innerhalb des morphogenetischen Feldes veranlassen, welche Differenzierung sich bildet innerhalb eines bestimmten Bereichs der Feldintensität. Auf Grund der obigen Hypothese wird ein “virginelles” morphogenetisches Feld zwangsläufig sich differenzieren in eine Anzahl kleinerer Feldern zweiten Grades; diese in Felder dritten Grades, usw. Musterbildung könnte definiert werden als die Differenzierung eines morphogenetischen Feldes in eine zunehmende Anzahl kleinerer Felder höheren Grades von qualitativ verschiedener chemischen und strukturellen Zusammensetzung, Weil diese Differenzierung autonom vor sich geht, ist das Vermögen zur Musterbildung eine innewohnende Eigenschaft eines morphogenetischen Feldes. Im Lichte dieser Betrachtungen ist es naheliegend anzunehmen dass eine morphogenetische Feldwirkung verantwortlich ist für die erste Differenzierung des sich entwickelnden Embryos in Gebiete überwiegend ektodermalen, mesodermalen oder entodermalen Differenzierungstendenzen. Die heutigen Kenntnisse über die charakteristische Musterbildung im axialen Teil des Mesoderms und in der überliegenden Neuralplatte scheinen in guter Übereinstimmung zu sein mit den des morphogenetischen Feldbegriffs. Dennoch wird benachdruckt, dass, falls das gegenwärtige morphogenetische Feldbegriff nicht weiter biochemisch und biophysisch gekennzeichnet werden kann, anstatt dessen ein anderer Begriff entwickelt werden muß, der schärfer definiert werden kann und besser zugänglich ist für experimentelle Analyse. (shrink)

Plant morphogenesis exhibits numerous bifurcations with particular angle values such as 41°, 53°, which, in lower plants, can be measured in the thallus, and, in higher plants, in the ribs of the leaves. An interpretation of these angles is attempted. Since they characterize the functioning of a morphogenetic field, a formalism was constructed suitable for the study of living systems. The mathematical tool devised here, named the Arithmetical Relator, combines Geometry and Arithmetic, and assumes that a general system (...) results from the interaction between an internal cyclic structure and an environment to which this structure is adapted. The formalism described therefore takes into account partial self-reference and changes in the level of organization. Within this framework, the particular values of the ramification angles are extreme for slight shifts in the internal structure. A pattern of the relations between the genome, the cell and the organ is suggested. (shrink)

Research in the field of planarian regeneration on the one hand, and a general survey of embryology on the other, throw doubt upon the reality of supra-cellular controls, which are still at the basis of all modern concepts of morphogenesis. The necessity of referring to such controls, which have never been convincingly demonstrated, is probably due to the fact that two aspects of cell behaviour have been underestimated: 1) the capacity of cells to change their individualities for a time (...) independently of other cells; 2) the social behaviour of cells, which is the consequence of the reciprocal exchange of information. Pattern formation and pattern remodeling in normal development results from readjustments of cell populations to local or global changes. The common responses of cell populations to disturbances are enhanced mitotic activity, cessation of specific syntheses and cell migration. In the young embryo these may promptly restore the unity of the injured primordium, leading to so-called restitution; this is based on a normal sequence of further readjustments in the primordium. In older organisms the same responses give rise to cell interactions which may be the starting point for further sequential readjustments — in some instances these are comparable to those that originally organized the primordium in question during development. The desirability of giving up the notion of morphogenetic field is discussed. (shrink)

Polanyi’s vision of the cosmic process as undergirded by a logic of emergence common to both the mental life of human beings and the processes of non-human nature can be vindicated if one is prepared to make certain adjustments in the notion of morphogenetic fields with an active center or organizing principle. Given the author’s field-oriented interpretation of Whiteheadian societies, it should be possible to think of entelechies or final causes in developmental rather than strictly Aristotelian terms. That (...) is, the “common element of form” or organizing principle of a Whiteheadian society depends for its own existence on the spontaneous activity of previous sets of actual occasions and yet serves as the ongoing principle of formal and final causality for the present set of actual occasions and still others to follow it. In Aristotelian language, matter and form thus dialectically condition one another and neither is ontologically superior to the other. (shrink)

A model is proposed that deals with the observed collinearities (spatial, temporal and quantitative) of Hox gene expression during pattern formation along the primary and secondary axes of vertebrates. In particular, in the proximodistal axis of the developing limb, it is assumed that a morphogen gradient is laid down with its source at the distal tip of the bud. The extracellular signals in every cell of the morphogenetic field are transduced and uniformly amplified so that molecules are produced (...) in the nucleus with appropriate physicochemical properties. These molecules can exert a concentration‐dependent force on the Hox cluster. It is assumed that, before activation, the Hox cluster is packaged as an elongated rigid body inside the chromatin and is covered by a coat that prevents the transcription factors reaching the genes of the cluster. The transcription factors are confined to the interchromatin domain and their density decreases with their distance from the chromatin surface. A gradual increase in the extracellular morphogen concentration causes a corresponding increase in the number of the nuclear molecules and the resulting bigger force pushes the Hox cluster toward the interchromatin domain. The step‐by‐step translocations of the Hox cluster initiate the consecutive exposure of genes to their transcription factors. The model explains how gene activation is triggered and it describes spatial, temporal and quantitative collinearities at the initial stages of gene expression. Some recent experiments of Hox deletions and duplications are accounted for by the model. BioEssays 26:189–195, 2004. © 2004 Wiley Periodicals, Inc. (shrink)

Syntax is better viewed as the dynamics of a morphogenetic field on a semantic universe of “content” words. This may take widely different forms, making the acquisition of any language by an aspiring speaker an entirely new experience. The existence of an underlying “universal syntax” might be illusory.

The homologies of process within morphogenetic fields provide some of the best evidence for evolution—just as skeletal and organ homologies did earlier. Thus, the evidence for evolution is better than ever. The role of natural selection in evolution, how–ever, is seen to play less an important role. It is merely a filter for unsuccessful morphologies generated by development. Population genetics is destined to change if it is not to become as irrelevant to evolution as Newtonian mechanics is to contempo–rary (...) physics. (shrink)

The homologies of process within morphogenetic fields provide some of the best evidence for evolution—just as skeletal and organ homologies did earlier. Thus, the evidence for evolution is better than ever. The role of natural selection in evolution, however, is seen to play less an important role. It is merely a filter for unsuccessful morphologies generated by development. Population genetics is destined to change if it is not to become as irrelevant to evolution as Newtonian mechanics is to contemporary (...) physics. (Gilbert, Opitz, and Raff 1996, 368). (shrink)

In the present paper, we explore the impact of singing for girls in rural Bangladesh. Previous findings in this field-based interview study (with 18 girls) have demonstrated that singing can act as a driving force in young girls’ psychological individuation processes, implying increased agency and autonomy. A critical question, however, is to what extent the village girls will manage to maintain a feeling of agency as they pass through puberty. How do they navigate between their own wish to continue (...) singing and pressure from cultural norms (such as getting married)? Using Margareth Archer’s morphogenetic approach and Arjun Appadurai’s approach to culture as a capacity as analytical tools, we connect different modes of reflexivity to the girls’ capacity to aspire. We discuss specific mechanisms that emerge as relevant for the girls/young women as they navigate their way through the Bengali rural society. (shrink)

Two approaches to an integration of evolution and development are often distinguished, one neo-Darwinian and the other structuralist. Should these approaches in turn be integrated? Kelly Smith recently stated that we need a more complete theory of biological order, suggesting integration as the ideal. In response to him, I argue that a recognition of different types of scientific questions and causal explanation is more urgent. Do we understand development when we know the crucial factors in the process of differentiation, or (...) rather when we know the laws that govern the transformations of fields? Without a recognition of these different explanatory ideals, integration is likely to have the character of annexation. (shrink)

Morphological EvoDevo is a field of biological inquiry in which explicit relations between evolutionary patterns and growth or morphogenetic processes are made. Historically, morphological EvoDevo results from the coming together of several traditions, notably Naturphilosophie, embryology, the study of heterochrony, and developmental constraints. A special feature binding different approaches to morphological EvoDevo is the use of formalisms and mathematical models. Here we will introduce anatomical network analysis, a new approach centered on connectivity patterns formed by anatomical parts, with (...) its own concepts and tools specifically designed for the study of morphological EvoDevo questions. Riedl’s concept of burden is tightly related to the use of anatomical networks, providing a nexus between the evolutionary patterns and the structural constraints that shape them. (shrink)

Despite the transformation in biological practice and theory brought about by discoveries in molecular biology, until recently philosophy of biology continued to focus on evolutionary biology. When the Human Genome Project got underway in the late 1980s and early 1990s, philosophers of biology -- unlike historians and social scientists -- had little to add to the debate. In this landmark collection of essays, Sahotra Sarkar broadens the scope of current discussions of the philosophy of biology, viewing molecular biology as a (...) unifying perspective on life that complements that of evolutionary biology. His focus is on molecular biology, but the overriding question behind these papers is what molecular biology contributes to all traditional areas of biological research.Molecular biology -- described with some foresight in a 1938 Rockefeller Foundation report as a branch of science in which "delicate modern techniques are being used to investigate ever more minute details" -- and its modeling strategies apparently argue in favor of physical reductionism. Sarkar's first three chapters explore reductionism -- defending it, but cautioning that reduction to molecular interactions is not necessarily a reduction to genetics. The next sections of the book discuss function, exploring how functional explanations pose a problem for reductionism; the informational interpretation of biology and how it interacts with reductionism; and the tension between the unifying framework of molecular biology and the received framework of evolutionary theory. The concluding chapter is an essay in the emerging field of developmental evolution, exploring what molecular biology may contribute to the transformation of evolutionary theory as evolutionary theory takes into account morphogenetic development. (shrink)

This contributed volume aims to reconsider the concept of individuation, clarifying its articulation with respect to contemporary problems in perceptual, neural, developmental, semiotic and social morphogenesis. The authors approach the ontogenetical issue by taking into account the morphogenetical process, involving the concept of individuation proposed by Gilbert Simondon and Gilles Deleuze. The target audience primarily comprises experts in the field but the book may also be beneficial for graduate students. The challenge of the genesis and constitution of "units" has (...) always been at the center of philosophical and scientific research. This ontogenetical issue is common to every discipline but it is articulated in different ways: in phenomenology of perception the constitution of perceptual units is at the base of gestalt field theories, in theoretical neuroscience synchronized neural assemblies are considered as correlates of conscious processes, in developmental embryogenesis the constitution of organs is the principle outcome of morphodynamic evolution while in social morphogenesis the constitution of coherent units is common to segmentary, gerarchic and functional differentiation. (shrink)

This paper takes up some threads of Deleuze’s and Ruyer’s engagement with biology. I begin by laying out the main features of Deleuze’s scheme of morphogenesis, through the lens of his references to embryology. I take Deleuze’s interest in embryology to be guided by the effort to define bodies solely by form-generating factors which are immanent to them. His concept of virtuality, which indicates the creative component of reality, the open field of connections defining a body’s capacities for transformation (...) and interaction, plays a key role in this regard. I then consider two implications: (1) The insistence on morphogenesis displaces the question of life from given biological entities, which preserve themselves and act through regulated cycles, to the myriad of activities that compose and modify them; (2) It also rearticulates the distinction between the living and the nonliving, in that it separates the question of life from that of its emergence from a given material arrangement. In the second part I examine these points with greater reference to Ruyer. After introducing Ruyer’s concepts of functioning and formation, I focus on his account of the continuity between biological and physicochemical forms, following some of his work on the microbiology and ethology of the time. The real difference is not between the living and the nonliving, but between two modes of bonding and composition variously operating on all scales: morphogenetic and statistical. I conclude by assessing the significance of this claim with respect to the traditional distinction between vitalism and mechanism. (shrink)

Large‐scale patterns of correlated growth in development are partially driven by competition for metabolic and informational resources. It is argued that competition between organs for limited resources is an important mesoscale morphogenetic mechanism that produces fitness‐enhancing correlated growth. At the genetic level, the growth of individual characters appears independent, or “modular,” because patterns of expression and transcription are often highly localized, mutations have trait‐specific effects, and gene complexes can be co‐opted as a unit to produce novel traits. However, body (...) parts are known to interact over the course of ontogeny, and these reciprocal exchanges can be an important determinant of developmental outcomes. Genetic mechanisms underlie cell and tissue behaviors that allow organs to communicate with one another, but they also create evolutionarily adaptive competitive dynamics that are driven by physiological and biophysical processes. Advances in the understanding of competitive and closely related coordinative interactions across scales will complement existing research programs that emphasize the role of cellular mechanisms in morphogenesis. Study of the large‐scale order produced by competitive dynamics promises to facilitate advances in basic evolutionary and developmental biology, as well as applied research in fields such as bioengineering and regenerative medicine that aim to regulate patterning outcomes. (shrink)

Critical realism is a philosophy of science, which has made significant contributions to epistemic debates within sociology. And yet, its contributions to ethnographic explanation have yet to be fully elaborated. Drawing on ethnographic data on the health-seeking behavior of HIV-infected South Africans, the paper compares and contrasts critical realism with grounded theory, extended case method and the pragmatist method of abduction. In so doing, it argues that critical realism makes a significant contribution to causal explanation in ethnographic research in three (...) ways: 1) by linking structure to agency; 2) by accounting for the contingent, conjunctural nature of causality; and 3) by using surprising empirical findings to generate new theory. The paper develops the AART research schema and illustrates its strengths by employing a Bourdieusian field analysis as a model for morphogenetic explanation. (shrink)

Critical realism is a philosophy of science, which has made significant contributions to epistemic debates within sociology. And yet, its contributions to ethnographic explanation have yet to be fully elaborated. Drawing on ethnographic data on the health-seeking behavior of HIV-infected South Africans, the paper compares and contrasts critical realism with grounded theory, extended case method and the pragmatist method of abduction. In so doing, it argues that critical realism makes a significant contribution to causal explanation in ethnographic research in three (...) ways: 1) by linking structure to agency; 2) by accounting for the contingent, conjunctural nature of causality; and 3) by using surprising empirical findings to generate new theory. The paper develops the AART research schema and illustrates its strengths by employing a Bourdieusian field analysis as a model for morphogenetic explanation. (shrink)

Homology continues to be a concept of central importance in the study of phylogenetic relations, but its relation to ontogenetic processes remains problematical. A definition of homology in terms of equivalent morphogenetic processes is defined and applied to the comparative study of tetrapod limbs. This allows for a consistent treatment of relations of similarity and difference of appendage structure in vertebrates, and the distinction between fishes fins and tetrapod limbs in terms of the concept of equivalence is described. The (...) role of genes can also be clarified in this context, in particular the influence of the Hox 4 complex in determining digit character and the homeotic transformations that arise from changes in their expression patterns. It is argued that these observations are not compatible with the notion of homology between individual digits (I, II, III, etc.) across the tetrapods, and that homology cannot be consistently identified with gene action. The relations between homology and the properties of the morphogenetic limb field are discussed. (shrink)

The growth of the vein system of the leaf ofTropaeolum peltophorum was studied at the vein level and at the limb level.The vein growth kinetics depend on the position of the vein on the leaf: there is a proximal/distal gradient and a bilateral gradient of the growth parameters. The growth field of the veins is also dependent on time and on vein position.Specific correspondences exist between singular points of the global growth curves, the variations of the growth field (...) and the vein position. The spatio-temporal organization of the vein system growth is then characterized by positional variations of kinetic order which show the existence of areal morphogenetic dissymmetry. (shrink)

This review is focused on recent advances in our understanding of the development of coordinated cell polarity, through experiments on the Drosophila compound eye. Each eye facet (or “ommatidium”) contains a set of eight photoreceptor cells, placed so that their rhabdomeres form an asymmetric trapezoid. The array of ommatidia is organized so that these trapezoids are aligned in two mirror-image fields, dorsal and ventral to the eye midline (or “equator”). The development of this pattern depends on two systems of positional (...) information that inform the cluster of cells that will form an ommatidium of anterior/posterior (a/p) and dorsal/ventral (d/v) direction. The former (a/p) is encoded by a progressive wave of development (the morphogenetic furrow). The latter (d/v) involves molecules known to act in tissue polarity in other organs and organisms. Our understanding of the function of these molecules rests not only on their mutant phenotypes, biochemistry, and expression patterns, but also on the spatial effects when mutant patches of cells are made (genetic mosaics). BioEssays 21:275–285, 1999. © 1999 John Wiley & Sons, Inc. (shrink)

This chapter considers the ways in which whiteness as a skin color and ideology becomes a dominant level that sets the background against which all things, people and relations appear. Drawing on Merleau-Ponty's phenomenology, it takes up a series of films by Bruce Nauman and Marlon Riggs to consider ways in which this level is phenomenally challenged providing insights into the embodiment of racialization.

Science Without Numbers caused a stir in 1980, with its bold nominalist approach to the philosophy of mathematics and science. It has been unavailable for twenty years and is now reissued in a revised edition with a substantial new preface presenting the author's current views and responses to the issues raised in subsequent debate.