The human fovea is known for its distinctive pit‐like appearance, which results from the displacement of retinal layers superficial to the photoreceptors cells. The photoreceptors are found at high density within the foveal region but not the surrounding retina. Efforts to elucidate the mechanisms responsible for these unique features have ruled out cell death as an explanation for pit formation and changes in cell proliferation as the cause of increased photoreceptor density. These findings have led to speculation that mechanical forces (...) acting within and on the retina during development underly the formation of foveal architecture. Here we review eye morphogenesis and retinal remodeling in human embryonic development. Our meta‐analysis of the literature suggests that fovea formation is a protracted process involving dynamic changes in ocular shape that start early and continue throughout most of human embryonic development. From these observations, we propose a new model for fovea development. (shrink)

During development of the anterior eye segment, cells that originate from the surface epithelium or the neuroepithelium need to interact with mesenchymal cells, which predominantly originate from the neural crest. Failures of proper interaction result in a complex of developmental disorders such Peters' anomaly, Axenfeld–Rieger's syndrome or aniridia. Here we review the role of transcription factors that have been identified to be involved in the coordination of anterior eye development. Among these factors is PAX6, which is active in both epithelial (...) and mesenchymal cells during ocular development, albeit at different doses and times. We propose that PAX6 is a key element that synchronizes the complex interaction of cell types of different origin, which are all needed for proper morphogenesis of the anterior eye. We discuss several molecular mechanisms that might explain the effects of haploinsufficiency of PAX6 and other transcription factors, and the broad variation of the resulting phenotypes. BioEssays 26:374–386, 2004. © 2004 Wiley Periodicals, Inc. (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)

Cell morphogenesis encompasses all processes required to establish a three-dimensional cell shape. Cells acquire the architecture specific to their developmental context by using the spatial information provided by internal or external cues. As a response to these signals, cells become reorganized and establish functionally distinct subcellular domains that ultimately lead to morphological changes. In its simplest form, cell morphogenesis results in the establishment of asymmetry along one axis, a cell polarity. Although cell polarity has been studied intensively in (...) budding yeast and epithelial cells, little is known about more complex modes of cell morphogenesis involving multiple axes. In this review we compare the regulation of cell morphogenesis of different genetically well-characterized cell types in Arabidopsis thaliana. BioEssays 20:20–29, 1998. © 1998 John Wiley & Sons, Inc. (shrink)

This book, the last volume in the Social Morphogenesis series, examines whether or not a Morphogenic society can foster new modes of human relations that could exercise a form of 'relational steering', protecting and promoting a nuanced version of the good life for all. It analyses the way in which the intensification of morphogenesis and the diminishing of morphostasis impact upon human flourishing. The book links intensified morphogenesis to promoting human flourishing based on the assumption that new (...) opportunities open up novel experiences, skills, and modes of communication that appeal to talents previously lacking any outlet or recognition. It proposes that equality of opportunity would increase as ascribed characteristics diminished in importance, and it could be maintained as the notion of achievement continued to diversify. Digitalization has opened the cultural 'archive' for more to explore and, as it expands exponentially, so do new complementary compatibilities whose development foster yet further opportunities. If more people can do more of what they do best, these represent stepping stones towards the 'good life' for more of them. (shrink)

Patterns resulting from the sole interplay between reaction and diffusion are probably involved in certain stages of morphogenesis in biological systems, as initially proposed by Alan Turing. Self-organization phenomena of this type can only develop in nonlinear systems (i.e. involving positive and negative feedback loops) maintained far from equilibrium. We present Turing patterns experimentally observed in a chemical system. An oscillating chemical reaction, the CIMA reaction, is operated in an open spatial reactor designed in order to obtain a pure (...) reaction-diffusion system. The two types of Turing patterns observed, hexagonal arrays of spots and parallel stripes, are characterized by an intrinsic wavelength. We identify the origin of the necessary difference of diffusivity between activator and inhibitor. We also describe a pattern growth mechanism by spot splitting that recalls cell division. (shrink)

A geometrical model is proposed that describes the emergence of a primordium at the shoot apex in Dicotyledons. It is based on recent fundamental results on plant morphogenesis, viz.: – the emergence is preceded by the reorganization of the microtubules of the cortical cytoskeleton, leading to a new orientation of the synthesis of the cell wall microfibrils; – the resulting global stress is related to the general orientation of the cell growth.

This article explores the ways new materialism centers the problem of morphogenesis—and de-centers language and culture—in philosophical accounts of corporeality. Attention to organic structures gives insight into the entanglement of nature and culture obscured by tendencies to think matter as lacking agential features. I suggest, in conclusion, that new materialism may operate with a notion of “entanglement” or “intra-activity” that is too productive. New materialisms may require a more pliable set of distinctions to capture the relations between morphogenetic forces.

Cell morphogenesis encompasses all processes required to establish a three-dimensional cell shape. Cells acquire the architecture specific to their developmental context by using the spatial information provided by internal or external cues. As a response to these signals, cells become reorganized and establish functionally distinct subcellular domains that ultimately lead to morphological changes. In its simplest form, cell morphogenesis results in the establishment of asymmetry along one axis, a cell polarity. Although cell polarity has been studied intensively in (...) budding yeast and epithelial cells, little is known about more complex modes of cell morphogenesis involving multiple axes. In this review we compare the regulation of cell morphogenesis of different genetically well-characterized cell types in Arabidopsis thaliana. BioEssays 20:20–29, 1998. © 1998 John Wiley & Sons, Inc. (shrink)

Ocular gene transfer clinical trials are raising hopes for blindness treatments and attracting media attention. News media provide an accessible health information source for patients and the public, but are often criticized for overemphasizing benefits and underplaying risks of novel biomedical interventions. Overly optimistic portrayals of unproven interventions may influence public and patient expectations; the latter may cause patients to downplay risks and over-emphasize benefits, with implications for informed consent for clinical trials. We analyze the news media communications landscape (...) about ocular gene transfer and make recommendations for improving communications between clinicians and potential trial participants in light of media coverage. (shrink)

Digital practices in design, together with computer-assisted manufacturing (CAM), have inspired the reflection of philosophers, theorists, and historians over the last decades. Gilles Deleuze’s The Fold: Leibniz and the Baroque (1988) presents one of the first and most successful concepts created to think about these new design and manufacturing practices.1 Deleuze proposed a new concept of the technological object, which was inspired by Bernard Cache’s digital design practices and computer-assisted manufacturing. Deleuze compared Cache’s practices to Leibniz’s differential calculus-based notion of (...) the parametric curve. From this perspective, the object is no longer an essential form: rather, it is functional, defined by a family of parametric curves. In Deleuze’s terms, it is an objectile. This definition grasps a particular aspect of modernity in the technological object, rendering possible the industrial production of “the unique object” (la pièce unique), while making obsolete the homogeneity that comes with industrial standardization. What follows introduces developmental biology into this design matrix, interrogating the relationship between parametric design and computer-assisted manufactory on the one hand and biological morphogenetic processes on the other. Is one necessary for the other? Does an architect need computation in order to render morphogenetic shapes? In answering these questions, this chapter displaces the centrality of digital technology in the design of shape-shifting forms within architecture and calls for a rethinking of design by way of analog prototypes. I argue that “thinking through analogs” offers another means of generating parametrically based morphogenetic forms. (shrink)

In 1952, Alan Turing published his last work on the concept of embryonic morphogenesis, propounding a computational framework for pattern formation within the developing embryo. This concept of morphogenesis and the concept of embryo pattern formation based on chemical diffusion patterns were corroborated with the discovery of the Homeobox or Hox genes. In the following decades, Hox gene research has expanded and is now shown to underlie the variety of morphological novelties that we experience in nature, the patterning (...) of structural aspects of different organs including the brain and also mutant animals that may in the future give rise to novel speciation. Turing had the foresight and vision and with his work created the field of computational biology and mathematical modeling in biological systems. In this paper, we will discuss the concept of Hox genes, their role in patterning the embryo, how it relates to Turing’s concept of morphogenesis and what further insights they may provide. (shrink)

Working within an Archerian morphogenetic framework, I suggest that we need to pay more attention to practices. Instead of the mainstream focus on practice as action, I argue that we should pay attention to practices as a key structural and cultural element of analysis. Practices cannot be simply read-off from beliefs, that is, they are not an inevitable practical counterpart to belief. Although belief is relevant, it does not provide the full explanation for the presence of practices. Therefore, the same (...) or similar beliefs can result in significantly different practices depending on factors such as advances in technology and changes in modes of dissemination of theological doctrine. To illustrate my argument, I consider historical work on comparative religious practices, specifically the distinction between rituals and routines. A focus on the latter, as the conditions of possibility for the former, leads to some implications for the thesis of the morphogenesis of contemporary society. An analysis of the relationship between religious rituals and routines stresses the importance of placing both in their wider cultural and structural context. (shrink)

Margaret S. Archer is responsible for important conceptual developments in critical realism and the structure-agent problem but her explanatory framework often opposes those of other influential theorists. In this book she provides a response to critics of her work in the form of a set of discussions of published articles.

Over the past decades, the notions of organic form and morphology—a scientific field historically associated with the eighteenth century polymath Johann Wolfgang von Goethe —have stealthy re-assumed a central role in various scientific disciplines. Although the study of organic form was apparently excluded from the main stage of evolutionary theory and biological sciences during the second half of the twentieth century, since morphology was considered as a descriptive and ancillary science unable to contribute to the neo-Darwinian synthesis of evolution1, morphological (...) concepts and approaches have now been re-brought onto the central stage of mainstream science.2In fact, several interdisciplinary... (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)

Alan M. Turing’s last published work and some posthumously published manuscripts were dedicated to the development of his theory of organic pattern formation. In “The Chemical Basis of Morphogenesis” (1952), he provided an elaborated mathematical formulation of the theory of the origins of biological form that had been first proposed by Sir D’Arcy Wendworth Thompson in On Growth and Form (1917/1942). While arguably his most mathematically detailed and his systematically most ambitious effort, Turing’s morphogenetical writings also form the most (...) thematically self-contained and least philosophically explored part of his work. We dedicate our inquiry to the reasons and the implications of Turing’s choice of biological topic and viewpoint. We will probe for possible factors in Turing’s choice that go beyond availability and acquaintance with On Growth and Form. On these grounds, we will explore how and to what extent his theory of morphogenesis actually ties in with his concept of mechanistic computation. Notably, Thompson’s pioneering work in biological ‘structuralism’ was organicist in outlook and explicitly critical of the Darwinian approaches that were popular with Turing’s cyberneticist contemporaries—and partly used by Turing himself in his proto-connectionist models of learning. Resolving this apparent dichotomy, we demonstrate how Turing’s quest for mechanistic explanations of how organisation emerges in nature leaves room for a non-mechanist view of nature. (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)

The postulate that events in peripheral vision enhance activity in the “fixate center” is called into question. An alternative explanation is used to account for the “remote distractor effect.” It is pointed out that a critical element of the model is missing.

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)

How Darwin's “endless forms most beautiful” have evolved remains one of the most exciting questions in biology. The significant variety of bacterial shapes is most likely due to the specific advantages they confer with respect to the diverse environments they occupy. While our understanding of the mechanisms generating relatively simple shapes has improved tremendously in the last few years, the molecular mechanisms underlying the generation of complex shapes and the evolution of shape diversity are largely unknown. The emerging field of (...) bacterial evolutionary cell biology provides a novel strategy to answer this question in a comparative phylogenetic framework. This relatively novel approach provides hypotheses and insights into cell biological mechanisms, such as morphogenesis, and their evolution that would have been difficult to obtain by studying only model organisms. We discuss the necessary steps, challenges, and impact of integrating “evolutionary thinking” into bacterial cell biology in the genomic era. (shrink)

This paper is devoted to computer modelling of the development and regeneration of multicellular biological structures. Some species are able to regenerate parts of their body after amputation damage, but the global rules governing cooperative cell behaviour during morphogenesis are not known. Here, we consider a simplified model organism, which consists of tissues formed around special cells that can be interpreted as stem cells. We assume that stem cells communicate with each other by a set of signals, and that (...) the values of these signals depend on the distance between cells. Thus the signal distribution characterizes location of stem cells. If the signal distribution is changed, then the difference between the initial and the current signal distribution affects the behaviour of stem cells—e.g. as a result of an amputation of a part of tissue the signal distribution changes which stimulates stem cells to migrate to new locations, appropriate for regeneration of the proper pattern. Moreover, as stem cells divide and form tissues around them, they control the form and the size of regenerating tissues. This two-level organization of the model organism, with global regulation of stem cells and local regulation of tissues, allows its reproducible development and regeneration. (shrink)

One can use mathematics not as an instrument or measure, or a replacement for God, but as a poetic articulation, or perhaps as a stammered experimental approach to cultural dynamics. I choose to start with the simplest symbolic substances that respect the lifeworld’s continuous dynamism, temporality, boundless morphogenesis, superposability, continuity, density and value, and yet are independent of measure, metric, counting, finitude, formal logic, syntax, grammar, digitality and computability – in short, free of the formal structures that would put (...) a cage over all of the lifeworld. I call these substances topological media. This article introduces elementary topological concepts with which we can articulate material and cultural change using notions of proximity, limit, and change, without recourse to number or metric. The motivation is that topology furnishes us with concepts well-adapted for poietically articulating the world as stuff, rather than objects with an a priori schema. With care, it may provide a fruitful approach to morphogenesis and cultural dynamics that is neither reductive nor anthropocentric. I will not pretend any systematic application of the scaffolding concepts introduced in this article. Instead, I would see what fellow students of cultural dynamics and cosmopolitics make of these concepts in their own work. (shrink)

In this paper, I argue that the German morphological tradition made a major contribution to twentieth-century study of form. Several scientists paved the way for this research: paleontologist Adolf Seilacher, entomologist Hermann Weber, and biologist Johann-Gerhard Helmcke together with architect Frei Otto. All of them sought to examine morphogenetic processes to illustrate their inherent structural properties, thus challenging the neo-Darwinian framework of evolutionary theory. I point out that the German theoretical challenge to adaptationist thinking was possible through an exchange and (...) transfer of practices, data, technologies, and knowledge between biologically oriented students of form and architects, designers, and engineers. This exchange of practices and knowledge was facilitated by the establishment of two collaborative research centers at the beginning of the 1970s. Hence, by showing the richness of topics, methods, and technologies discussed in German-speaking morphology between 1950 and the 1970s, this paper paves the way to a much broader comprehension of the shifts that have shaped twentieth-century evolutionary biology. (shrink)

This article firstly criticizes Margaret Archer’s Morphogenetic Approach for being indecisive about the realist notion of emergence it proposes as well as for her inadequate account of structural conditioning. It is argued that critical realists’ conceptualizations of emergence cannot but lead to inconsistencies about the adequate placement of agents as parts of emergent entities. The inconsistencies to which these conceptualizations lead necessitate an anti-realist model of the constitution of societies which takes into account that social structures are existentially dependent upon (...) ideational elaboration. This alternative anti-realist theoretical perspective is provided by Ontogenesis, within the framework of which the realists’ idea of the ‘necessary and internal relations’ give their place to the ontological pervasiveness of the culturally shared imaginary schemata. Archer’s denial of a collective synchronic impact to social forms is implied in her analysis of morphogenetic cycles, according to which, structural elaboration post-dates social interaction; and this denial is also expressed in this very idea of emergent structures. Instead, for Ontogenesis, social forms are synchronically dependent on the collective impact of the differently socially placed agents, who have different interests and material resources, and whose interaction only becomes meaningful when drawing on these culturally shared imaginary schemata. (shrink)

Shortly after implantation the embryonic lineage transforms from a coherent ball of cells into polarized cup shaped epithelium. Recently we elucidated a previously unknown apoptosis‐independent morphogenic event that reorganizes the pluripotent lineage. Polarization cues from the surrounding basement membrane rearrange the epiblast into a polarized rosette‐like structure, where subsequently a central lumen is established. Thus, we provided a new model revising the current concept of apoptosis‐dependent epiblast morphogenesis. Cell death however has to be tightly regulated during embryogenesis to ensure (...) developmental success. Here, we follow the stages of early mouse development and take a glimpse at the critical signaling and morphogenic events that determine cells destiny and reshape the embryonic lineage. (shrink)

Luis Morales Dept. de Psicología y Sociología, Universidad de Zaragoza, España Los movimientos oculares nos informan acerca del procesamiento lingüístico. … Read More →.

Luca Del Baldo's Visionary Academy of Ocular Mentality is an extraordinary testament in the recent history of visual studies. It brings together a group of outstanding scholars who have devoted their lives to art history, philosophy, history, ethnology, focussing predominantly on questions of human perception and imagination. Working from photographs provided by the scholars, Luca del Baldo painted his series of 96 portraits reproduced in this book. The portraits are accompanied by texts written by the persons portrayed, in response (...) to their portrayal, and as an exchange: the artist gifted the original painting to the portrayed person, and the portrayed gifted her or his response. "The result is a unique and profound conversation between image and text focussed on the enigma of the human face in all its mediations.". (shrink)

Morphogenesis is a general concept in biology including all the processes which generate tissue shapes and cellular organizations in a living organism. Many hybrid formalizations have been proposed for modelling morphogenesis in embryonic or adult animals, like gastrulation. We propose first to study the ventral furrow invagination as the initial step of gastrulation, early stage of embryogenesis. We focus on the study of the connection between the apical constriction of the ventral cells and the initiation of the invagination. (...) For that, we have created a 3D biomechanical model of the embryo of the Drosophila melanogaster based on the finite element method. Each cell is modelled by an elastic hexahedron contour and is firmly attached to its neighbouring cells. A uniform initial distribution of elastic and contractile forces is applied to cells along the model. Numerical simulations show that invagination starts at ventral curved extremities of the embryo and then propagates to the ventral medial layer. Then, this observation already made in some experiments can be attributed uniquely to the specific shape of the embryo and we provide mechanical evidence to support it. Results of the simulations of the “pill-shaped” geometry of the Drosophila melanogaster embryo are compared with those of a spherical geometry corresponding to the Xenopus lævis embryo. Eventually, we propose to study the influence of cell proliferation on the end of the process of invagination represented by the closure of the ventral furrow. (shrink)

This paper is devoted to computer modelling of the development and regeneration of multicellular biological structures. Some species are able to regenerate parts of their body after amputation damage, but the global rules governing cooperative cell behaviour during morphogenesis are not known. Here, we consider a simplified model organism, which consists of tissues formed around special cells that can be interpreted as stem cells. We assume that stem cells communicate with each other by a set of signals, and that (...) the values of these signals depend on the distance between cells. Thus the signal distribution characterizes location of stem cells. If the signal distribution is changed, then the difference between the initial and the current signal distribution affects the behaviour of stem cells—e.g. as a result of an amputation of a part of tissue the signal distribution changes which stimulates stem cells to migrate to new locations, appropriate for regeneration of the proper pattern. Moreover, as stem cells divide and form tissues around them, they control the form and the size of regenerating tissues. This two-level organization of the model organism, with global regulation of stem cells and local regulation of tissues, allows its reproducible development and regeneration. (shrink)