Background: One of the all-time questions in evolutionary biology regards the evolution of organismal shapes, and in particular why certain forms appear repeatedly in the history of life, others only seldom and still others not at all. Recent research in this field has deployed the conceptual framework of constraints and natural selection as measured by quantitative genetic methods. Scope: In this paper I argue that quantitative genetics can by necessity only provide us with useful statistical sum- maries that may lead (...) researchers to formulate testable causal hypotheses, but that any inferential attempt beyond this is unreasonable. Instead, I suggest that thinking in terms of coordinates in phenotypic spaces, and approaching the problem using a variety of empirical methods (seeking a consilience of evidence), is more likely to lead to solid inferences regarding the causal basis of the historical patterns that make up most of the data available on phenotypic evolution. (shrink)

Abstract In his critique of modern libertarian thinking, Jeffrey Friedman (1997) argues that libertarian moral theory makes social science irrelevant. However, if its moral claims are hypothetical rather than categorical imperatives, then economics, history, sociology, and other disciplines play a central role in libertarian thought. Limitations on human knowledge necessitate abstractly formulated rules, among which are claims of rights. Further, Friedman's remarks on freedom rest on an erroneous understanding of the role of definitions in philosophy, and his characterization of the (...) ?right to do wrong? as a ?logical contradiction? reveals a misunderstanding of logic. (shrink)

The architecture of brain, consciousness, and behavioral processes is shown to be formally similar in that all three may be conceived and depicted as Petri net patterned processes structured by a series of elements occurring or becoming active in stochastic succession, in parallel, with different rhythms of temporal iteration, and with a distinct qualitative manifestation in the spatiotemporal domain. A patterned process theory is derived from the isomorphic features of the models and contrasted with connectionist, dynamic system notions. This empirically (...) derived formulation is considered to be optimally compatible with the dual aspect theory in that the foundation of the diverse aspects would be a highly structured and dynamic process, the psychophysical neutral “ground” of mind and matter posed (but not properly determined) by dual aspect and neutral monist theories. It is methodologically sound to approach each one of these processes with specific tools and to establish concurrences in real time between them at the organismic level of analysis. Such intra‐level and inter‐perspective correlations could eventually constitute psychophysical bridge‐laws. A mature psychology of consciousness is necessary to situate and verify the bridges required by a genuine mind‐body science. (shrink)

The cell theory—the thesis that all life is made up of one or more cells, the fundamental structural and physiological unit—is one of the most celebrated achievements of modern biological science. And yet from its very inception in the nineteenth century it has faced repeated criticism from some biologists. Why do some continue to criticize the cell theory, and how has it managed nevertheless to keep burying its undertakers? The answers to these questions reveal the complex nature of the cell (...) theory and the cell concept on which it is based. Like other scientific ‘laws’, the assertion that all living things are made of cells purchases its universality at the expense of abstraction. If, however, this law is regarded merely as a widely applicable empirical generalization with notable exceptions, it still remains too important to discard. Debate about whether the cell or the organism standpoint provides the more correct account of anatomical, physiological, and developmental facts illustrates the tension between our attempts to express the truth about reality in conceptual terms conducive to a unified human understanding. (shrink)

ig Brother, the tyrant of George Orwell's 1984, directed his daily Two Minutes Hate against Emmanuel Goldstein, enemy of the people. When I studied evolutionary biology in graduate school during the mid 1960s, official rebuke and derision focused upon Richard Goldschmidt , a famous geneticist who, we were told, had gone astray. Although 1984 creeps up on us, I trust that the world will not be in Big Brother's grip by then. I do, however, predict that during this decade Goldschmidt (...) will be largely vindicated in the world of evolutionary biology. (shrink)

A spiral running along the surface of a cone standing on top is proposed as a model for evolution, the progress of which is considered as composed of a linear progression following the direction of time and representing the linear increase in the number of taxa, while a circular component stands for the ever recurring functional types of organisms.

The authors constructed an algorithm that relates leaf contour to the ratio between the two parts of the leaf using the function θ’=nθm, wherem is the allometric exponent. Using this model, it is possible to simulate the contour of symmetrical or asymmetrical leaves. The authors hypothesize that the portion of the leaf contour that agrees with the simulation is linked to a constraint imposed by the initial asymmetry of the leaf primordium. The final shape of the leaf results more from (...) a summation of cumulative processes through time than from a single process. In the analysis of foliar allometry, it is important to take into consideration the different phases of leaf development, since the nature of the allometric constants may change from one phase to the next, even though their numerical value may remain the same. (shrink)

A functional approach to evolutionary morphology is emphasized in this paper. This perspective differs from the current structuralist trend, which emphasizes the constraining role of developmental paths. In addition, the present approach agrees with the adaptationist paradigm. It is further argued that three types of phenomena are better understood in this light: i.- the existence of evolutionary trends, ii.- the maintenance of certain structural features within a given taxon, and iii.- the irreversibility of evolution.

It is widely felt that the sorts of ideas current in modern laterality and split-brain research are largely without precedent in the behavioral and brain sciences. This paper not only challenges that view, but makes a first attempt to define the relevance of older concepts and data to present research programs.

Given the personal acquaintance between Alan M. Turing and W. Ross Ashby and the partial proximity of their research fields, a comparative view of Turing’s and Ashby’s work on modelling “the action of the brain” (letter from Turing to Ashby, 1946) will help to shed light on the seemingly strict symbolic/embodied dichotomy: While it is clear that Turing was committed to formal, computational and Ashby to material, analogue methods of modelling, there is no straightforward mapping of these approaches onto symbol-based (...) AI and embodiment-centered views respectively. Instead, it will be demonstrated that both approaches, starting from a formal core, were at least partly concerned with biological and embodied phenomena, albeit in revealingly distinct ways. (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)

This study analyzes shells of marine gastropods of a zoological museum and the Latin epithets expressing perceptual and connotative attributes that they have received in the standard, Linnaean nomenclature. Making use of the Osgood semantic differential, we presented the subjects with digital 3-D reproductions of the shell specimens to be subjectively evaluated according to 17 pairs of attributes. The results show that, overall, the subjective evaluations given by the subjects are consistent, which suggests that an intersubjective characterization of the shells (...) as wholes according to their qualitative and morphological traits is possible and scientifically explicable. This may apply to other biological items as well. The results also show that the epithets given to the shells by taxonomists do not always reflect the perceptual evaluation of the general population, being a product of the well-known ambiguity in taxonomic categorization and naming. (shrink)

“Emergence” – the notion of novel, unpredictable and irreducible properties developing out of complex organisational entities – is itself a complex, multi-dimensional concept. To date there is no single, generally agreed upon “theory of emergence”, but instead a number of different approaches and perspectives. Neither is there a common conceptual or meta-theoretical framework by which to systematically identify, exemplify and compare different “theories”. Building upon earlier work done by sociologist Kenneth Bailey, this article presents a method for creating such a (...) framework, and outlines the conditions for a collaborative effort in order to carry out such a task. A brief historical and theoretical background is given both to the concept of “emergence” and to the non-quantified modelling method General Morphological Analysis (GMA). (shrink)

I show that there are good arguments and evidence to boot that support the language as an instrument of thought hypothesis. The underlying mechanisms of language, comprising of expressions structured hierarchically and recursively, provide a perspective (in the form of a conceptual structure) on the world, for it is only via language that certain perspectives are avail- able to us and to our thought processes. These mechanisms provide us with a uniquely human way of thinking and talking about the world (...) that is different to the sort of thinking we share with other animals. If the primary function of language were communication then one would expect that the underlying mechanisms of language will be structured in a way that favours successful communication. I show that not only is this not the case, but that the underlying mechanisms of language are in fact structured in a way to maximise computational efficiency, even if it means causing communicative problems. Moreover, I discuss evidence from comparative, neuropatho- logical, developmental, and neuroscientific evidence that supports the claim that language is an instrument of thought. (shrink)

Life scientists increasingly rely upon abstraction-based modeling and reasoning strategies for understanding biological phenomena. We introduce the notion of constraint-based reasoning as a fruitful tool for conceptualizing some of these developments. One important role of mathematical abstractions is to impose formal constraints on a search space for possible hypotheses and thereby guide the search for plausible causal models. Formal constraints are, however, not only tools for biological explanations but can be explanatory by virtue of clarifying general dependency-relations and patterning between (...) functions and structures. We describe such situations as constraint-based explanations and argue that these differ from mechanistic strategies in important respects. While mechanistic explanations emphasize change-relating causal features, constraint-based explanations emphasize formal dependencies and generic organizational features that are relatively independent of lower-level changes in causal details. Our distinction between mechanistic and constraint-based explanations is pragmatically motivated by the wish to understand scientific practice. We contend that delineating the affordances and assumptions of different explanatory questions and strategies helps to clarify tensions between diverging scientific practices and the innovative potentials in their combination. Moreover, we show how constraint-based explanation integrates several features shared by otherwise different philosophical accounts of abstract explanatory strategies in biology. (shrink)

The philosophy of biomimicry, I argue, consists of four main areas of inquiry. The first, which has already been explored by Freya Mathews, concerns the “deep” question of what Nature ultimately is. The second, third, and fourth areas correspond to the three basic principles of biomimicry as laid out by Janine Benyus. “Nature as model” is the poetic principle of biomimicry, for it tells us how it is that things are to be “brought forth”. “Nature as measure” is the ethical (...) principle of biomimicry, for it tells us that Nature places ethical limits or standards on what it is possible for us to accomplish. And “Nature as mentor” is the epistemological principle of biomimicry, for it affirms that Nature is the ultimate source of truth, wisdom, and freedom from error. Within this overall framework, I argue that seeing Nature as physis—understood as “self-production” or “self-placing-into-the-open”—constitutes the requisite ground for the poetic, ethical, and epistemological principles of biomimicry, and that biomimicry thus conceived involves a new philosophical paradigm, which I call “enlightened naturalism”. (shrink)

Two hundred years after Darwin’s birth, the evolution of living systems is an accepted fact but there is scope for controversy on the mechanisms involved in such a process. Mainstream neo-Darwinism champions the role of natural selection (NS) as the fundamental cause of the evolutionary process as well as of random, contingent events at the genetic level as the main source of variation upon which NS performs its causal role. Thus, according to neo-Darwinism the course of biological evolution is quite (...) unpredictable and the past can only be partially reconstructed by means of a historical narrative.This second-class status for biology within the natural sciences as a merely descriptive, historical science results from the chronic neglect of biological form in the neo-Darwinian discourse. Hereunder I discuss the need for reintroducing form as the central object of biology, aiming at the identification of the general and fundamental principles of biological form. Such a formal biology may go beyond simple historical description achieving a complete, rational explanation of how previous and current morphologies corresponding to identifiable species were established, and so providing a rational foundation for predicting the possible outcomes of future biological evolution on earth and perhaps elsewhere in the universe. (shrink)

In 1979, Lewontin and I borrowed the archi- tectural term “spandrel” (using the pendentives of San Marco in Venice as an example) to designate the class of forms and spaces that arise as necessary byproducts of another decision in design, and not as adaptations for direct utility in them- selves. This proposal has generated a large literature featur- ing two critiques: (i) the terminological claim that the span- drels of San Marco are not true spandrels at all and (ii) the (...) conceptual claim that they are adaptations and not byprod- ucts. The features of the San Marco pendentives that we explicitly defined as spandrel-properties—their necessary number (four) and shape (roughly triangular)—are inevitable architectural byproducts, whatever the structural attributes of the pendentives themselves. The term spandrel may be extended from its particular architectural use for two- dimensional byproducts to the generality of “spaces left over,” a definition that properly includes the San Marco pendentives. Evolutionary biology needs such an explicit term for features arising as byproducts, rather than adaptations, whatever their subsequent exaptive utility. The concept of biological span- drels—including the examples here given of masculinized genitalia in female hyenas, exaptive use of an umbilicus as a brooding chamber by snails, the shoulder hump of the giant Irish deer, and several key features of human mentality— anchors the critique of overreliance upon adaptive scenarios in evolutionary explanation. Causes of historical origin must always be separated from current utilities; their conf lation has seriously hampered the evolutionary analysis of form in the history of life. (shrink)

It is now well documented that biology needs morphometrics. Morphometrics can provide useful and often unexpected information about development and growth, functional—especially mechanical—adaptation, and evolutionary difference and relationship. Such studies often apply coordinate data from anatomical landmarks. Recently semi-landmarks and sliding landmarks increase information content, especially of apparently featureless regions . Yet, how we landmark our materials limits the results we get and the questions we ask. Here we show different landmarking schemes leading to different equivalences between specimens and different (...) results. Geometric morphometric methods often treat landmarks as points on rubber sheets. Distortions of the sheets are often visualized by techniques like thin plate splines showing changes or differences as stretches or contractions. The statistics of morphometrics can handle these. Further consideration of anatomical landmarks, however, implies that real biologies are sometimes more complex. Sometimes two-dimensional rubber sheets of anatomies contain cusps or holes representing appearances or disappearances of structures. In three dimensions, equivalent rubber blocks may show not only appearances or disappearances but also reversals of positions of structures. Such phenomena are generally ignored in landmarks and analyses. We show that in some cases morphometrics can take account of such matters. But we also suggest that sometimes these modifications from elastic analogues are so complex that new methods may be required for our morphometric packages. It is in this sense that improvement of morphometrics needs deeper understanding of biology. (shrink)

Since Darwin's theory of evolution by natural selection, the idea of descent with modification came to dominate systematics, and so the study of morphology became subgugated to the reconstruction of phylogenies. Reinstating the organism in the theory of evolution (Ho & Saunders, 1979; Webster & Goodwin, 1982) leads to a project inrational taxonomy (Ho, 1986, 1988a), which attempts to classify biological forms on the basis of transformations on a given dynamical structure.Does rational taxonomy correspond to thenatural system that Linnaeus and (...) his contemporaries as well as all pre-Darwinian morphologists had in mind? Here, we examine how rational taxonomy and the natural system can coincide in the dynamics of processes generating forms during development, which conferexclusivity, genericity androbustness to the forms that do exist. We use the example of segmentation, especially inDrosophila, as an illustration to explore the implications of rational taxonomy for evolution and systematics, and the relationship between ontogeny and phylogeny. (shrink)

Heyes’ book is an important contribution that rightly integrates cognitive development and cultural evolution. However, understanding the cultural evolution of cognitive gadgets requires a deeper appreciation of complexity, feedback, and self-organization than her book exhibits.

This essay presents a scenario of the origin of life that is based on analysis of biological architecture and mechanical design at the microstructural level. My thesis is that the same architectural and energetic constraints that shape cells today also guided the evolution of the first cells and that the molecular scaffolds that support solid-phase biochemistry in modern cells represent living microfossils of past life forms. This concept emerged from the discovery that cells mechanically stabilize themselves using tensegrity architecture and (...) that these same building rules guide hierarchical self-assembly at all size scales (Sci Amer 278:48–57;1998). When combined with other fundamental design principles (e.g., energy minimization, topological constraints, structural hierarchies, autocatalytic sets, solid-state biochemistry), tensegrity provides a physical basis to explain how atomic and molecular elements progressively self-assembled to create hierarchical structures with increasingly complex functions, including living cells that can self-reproduce. BioEssays 22:1160–1170, 2000. © 2000 John Wiley & Sons, Inc. (shrink)

In Making Sense of Life , Keller emphasizes several differences between biology and physics. Her analysis focuses on significant ways in which modelling practices in some areas of biology, especially developmental biology, differ from those of the physical sciences. She suggests that natural models and modelling by homology play a central role in the former but not the latter. In this paper, I focus instead on those practices that are importantly similar, from the point of view of epistemology and cognitive (...) science. I argue that concrete and abstract models are significant in both disciplines, that there are shared selection criteria for models in physics and biology, e.g. familiarity, and that modelling often occurs in a similar fashion. (shrink)

To identify the neural components that make a brain ready for language, it is important to have well defined linguistic phenotypes, to know precisely what language is. There are two central features to language: the capacity to form signs (words), and the capacity to combine them into complex structures. We must determine how the human brain enables these capacities. A sign is a link between a perceptual form and a conceptual meaning. Acoustic elements and content elements, are already brain-internal in (...) non-human animals, but as categorical systems linked with brain-external elements. Being indexically tied to objects of the world, they cannot freely link to form signs. A crucial property of a language-ready brain is the capacity to process perceptual forms and contents offline, detached from any brain-external phenomena, so their “representations” may be linked into signs. These brain systems appear to have pleiotropic effects on a variety of phenotypic traits and not to be specifically designed for language. Syntax combines signs, so the combination of two signs operates simultaneously on their meaning and form. The operation combining the meanings long antedates its function in language: the primitive mode of predication operative in representing some information about an object. The combination of the forms is enabled by the capacity of the brain to segment vocal and visual information into discrete elements. Discrete temporal units have order and juxtaposition, and vocal units have intonation, length, and stress. These are primitive combinatorial processes. So the prior properties of the physical and conceptual elements of the sign introduce combinatoriality into the linguistic system, and from these primitive combinatorial systems derive concatenation in phonology and combination in morphosyntax. Given the nature of language, a key feature to our understanding of the language-ready brain is to be found in the mechanisms in human brains that enable the unique means of representation that allow perceptual forms and contents to be linked into signs. (shrink)

Self-assembly processes of crystallization, micelle formation and virus assembly, by their creation of geometric order from disordered components, represent first-order phase transitions that arise through the formation of partially ordered intermediates. The self-assembly of protein subunits into the geometric shells of polyhedral viruses may proceed through formation of reverse micelles, and be driven by condensation of encapsidated nucleic acid complexed with the amino terminal polypeptides of the coat proteins. Restructuring of subunits on the fluid, micellar surface, analogous to processes on (...) the surfaces of growing crystals, then leads to symmetrical, icosahedral capsids. Such a pathway for viral assembly is attractive because it utilizes only physical properties inherent to the system, and it shares many characteristics that we know to be associated with those two other preeminent examples of self-assembly, micelles and crystals. BioEssays 27:447–458, 2005. © 2005 Wiley periodicals, Inc. (shrink)