Tetrahymena has been used as a model cell system in many studies of morphogenesis, conjugation, gene mapping, cell division and growth kinetics. In this article, we consider some advances which have resulted from the successful development of a chemically defined medium (CDM), and how subsequent work has extended the contribution that this organism has made to our understanding of different aspects of growth, nutrition, cell cycle control, cytokinesis and intercellular signalling. Finally, we discuss the considerable potential that has arisen for (...) the biotechnological exploitation of this big and rapidly growing eukaryotic cell. (shrink)

For many years, biology was largely descriptive (natural history), but with its emergence as a scientific discipline in its own right, a reductionist approach began, which has failed to be matched by adequate understanding of function of cells, organisms and species as whole entities. Every effort was made to explain biological phenomena in physico-chemical terms.It is argued that there is and always has been a clear distinction between life sciences and physical sciences, explicit in the use of the word biology. (...) If this distinction is real, it implies that biological phenomena can never be entirely satisfactorily explained in terms of extant physicochemical laws. One notable manifestation of this is that living organisms appear to -- actually do -- behave in purposeful ways, and the inanimate universe does not. While this fundamental difference continues to be suppressed, the purposiveness (or teleology) which pervades biology remains anathema to almost all scientists (including most biologists) even to the present day. We argue here that it can, however, become a perfectly tenable position when the Theory of Natural Selection is accepted as the main foundation, the essential tenet, of biology that distinguishes it from the realm of physical sciences. In accepting this position, it remains quite legitimate to expect that in many but not all circumstances, extant physical laws (and presumably others still to be discovered) are in no way breached by biological systems, which cannot be otherwise since all organisms are composed of physical material. (shrink)

Diffusion theory explains in physical terms how materials move through a medium, e.g. water or a biological fluid. There are strong and widely acknowledged grounds for doubting the applicability of this theory in biology, although it continues to be accepted almost uncritically and taught as a basis of both biology and medicine. Our principal aim is to explore how this situation arose and has been allowed to continue seemingly unchallenged for more than 150 years. The main shortcomings of diffusion theory (...) will be briefly reviewed to show that the entrenchment of this theory in the corpus of biological knowledge needs to be explained, especially as there are equally valid historical grounds for presuming that bulk fluid movement powered by the energy of cell metabolism plays a prominent note in the transport of molecules in the living body. First, the theory's evolution, notably from its origins in connection with the mechanistic materialist philosophy of mid nineteenth century physiology, is discussed. Following this, the entrenchment of the theory in twentieth century biology is analyzed in relation to three situations: the mechanism of oxygen transport between air and mammalian tissues; the structure and function of cell membranes; and the nature of the intermediary metabolism, with its implicit presumptions about the intracellular organization and the movement of molecules within it. In our final section, we consider several historically based alternatives to diffusion theory, all of which have their precursors in nineteenth and twentieth century philosophy of science. (shrink)

Drawing on the work of a wide range of thinkers, the authors offer a program for organizing and leading human activity in all types of organizations, based a ...

Whenever psychologists, neuroscientists, or philosophers draw conclusions about moral judgments in general from a small selected sample, they assume that moral judgments are unified by some common and peculiar feature that enables generalizations and makes morality worthy of study as a unified field. We assess this assumption by considering the six main candidates for a unifying feature: content, phenomenology, force, form, function, and brain mechanisms. We conclude that moral judgment is not unified on any of these levels and that moral (...) science should adopt a more fine-grained taxonomic approach that studies carefully defined groups of moral judgments. (shrink)

I am going to take the statement: “Value judgements are simply expressions of emotion”, as the kernel of the Emotive Theory and any variant of the Emotive Theory not covered by this statement is left untouched by what I have to say.

According to Aristotelian essentialism, the nature of an organism is constituted of a particular goal-directed disposition to produce an organism typical of its kind. This paper argues—against the prevailing orthodoxy—that essentialism of this sort is indispensable to evolutionary biology. The most powerful anti-essentialist arguments purport to show that the natures of organisms play no explanatory role in modern synthesis biology. I argue that recent evolutionary developmental biology provides compelling evidence to the contrary. Developmental biology shows that one must appeal to (...) the capacities of organisms to explain what makes adaptive evolution adaptive. Moreover, the specific capacities in question are precisely those that, according to Aristotle, constitute the nature of an organism. Essentialism 1.1 Aristotelian biological kinds Evolutionary anti-essentialism 2.1 Taxonomic anti-essentialism 2.2 Explanatory anti-essentialism Adaptation 3.1 Stability 3.2 Mutability 3.3 Phenotypic plasticity and adaptive evolution The natures of organisms Conclusion. (shrink)

An overview of the latest interdisciplinary research on human morality, capturing moral sensibility as a sophisticated integration of cognitive, emotional, and motivational mechanisms. Over the past decade, an explosion of empirical research in a variety of fields has allowed us to understand human moral sensibility as a sophisticated integration of cognitive, emotional, and motivational mechanisms shaped through evolution, development, and culture. Evolutionary biologists have shown that moral cognition evolved to aid cooperation; developmental psychologists have demonstrated that the elements that underpin (...) morality are in place much earlier than we thought; and social neuroscientists have begun to map brain circuits implicated in moral decision making. This volume offers an overview of current research on the moral brain, examining the topic from disciplinary perspectives that range from anthropology and neurophilosophy to justice and law. The contributors address the evolution of morality, considering precursors of human morality in other species as well as uniquely human adaptations. They examine motivations for morality, exploring the roles of passion, extreme sacrifice, and cooperation. They go on to consider the development of morality, from infancy to adolescence; findings on neurobiological mechanisms of moral cognition; psychopathic immorality; and the implications for justice and law of a more biological understanding of morality. These new findings may challenge our intuitions about society and justice, but they may also lead to more a humane and flexible legal system. Contributors Scott Atran, Abigail A. Baird, Nicolas Baumard, Sarah Brosnan, Jason M. Cowell, Molly J. Crockett, Ricardo de Oliveira-Souza, Andrew W. Delton, Mark R. Dadds, Jean Decety, Jeremy Ginges, Andrea L. Glenn, Joshua D. Greene, J. Kiley Hamlin, David J. Hawes, Jillian Jordan, Max M. Krasnow, Ayelet Lahat, Jorge Moll, Caroline Moul, Thomas Nadelhoffer, Alexander Peysakhovich, Laurent Prétôt, Jesse Prinz, David G. Rand, Rheanna J. Remmel, Emma Roellke, Regina A. Rini, Joshua Rottman, Mark Sheskin, Thalia Wheatley, Liane Young, Roland Zahn. (shrink)

There are two general approaches to characterising biological functions. One originates with Cummins. According to this approach, the function of a part of a system is just its causal contribution to some specified activity of the system. Call this the ‘C-function’ concept. The other approach ties the function of a trait to some aspect of its evolutionary significance. Call this the ‘E-function’ concept. According to the latter view, a trait's function is determined by the forces of natural selection. The C-function (...) and E-function concepts are clearly quite different, but there is an important relation between them which heretofore has gone unnoticed. The purpose of this paper is to outline that relation.This is not the first paper to discuss the relation of C-function and E-function. Previous attempts all follow either one of two strategies. The first proposes that the two concepts are ‘unified.’ The other proposes that they are radically distinct and apply to wholly different fields within biology. (shrink)

We distinguish dynamical and statistical interpretations of evolutionary theory. We argue that only the statistical interpretation preserves the presumed relation between natural selection and drift. On these grounds we claim that the dynamical conception of evolutionary theory as a theory of forces is mistaken. Selection and drift are not forces. Nor do selection and drift explanations appeal to the (sub-population-level) causes of population level change. Instead they explain by appeal to the statistical structure of populations. We briefly discuss the implications (...) of the statistical interpretation of selection for various debates within the philosophy of biologythe `explananda of selection' debate and the `units of selection' debate. (shrink)

Over the past fifteen years there has been a considerable amount of debate concerning what theoretical population dynamic models tell us about the nature of natural selection and drift. On the causal interpretation, these models describe the causes of population change. On the statistical interpretation, the models of population dynamics models specify statistical parameters that explain, predict, and quantify changes in population structure, without identifying the causes of those changes. Selection and drift are part of a statistical description of population (...) change; they are not discrete, apportionable causes. Our objective here is to provide a definitive statement of the statistical position, so as to allay some confusions in the current literature. We outline four commitments that are central to statisticalism. They are: 1. Natural Selection is a higher order effect; 2. Trait fitness is primitive; 3. Modern Synthesis (MS)-models are substrate neutral; 4. MS-selection and drift are model-relative. (shrink)

There are two competing interpretations of the modern synthesis theory of evolution: the dynamical (also know as ‘traditional’) and the statistical. The dynamical interpretation maintains that explanations offered under the auspices of the modern synthesis theory articulate the causes of evolution. It interprets selection and drift as causes of population change. The statistical interpretation holds that modern synthesis explanations merely cite the statistical structure of populations. This paper offers a defense of statisticalism. It argues that a change in trait frequencies (...) in a population can be attributed only to selection or drift against the background of a particular statistical description of the population. The traditionalist supposition that selection and drift are description‐independent causes of population change leads the dynamical interpretation into a dilemma: it must face a contradiction or accept the loss of explanatory power. (shrink)

The concept of the environment appears to be indispensably involved in adaptive explanation. Quite what its role is, however, is a matter of some dispute. The environment is customarily viewed as the dual of the organism; a wholly external, discrete, autonomous cause of evolution. On this view, the external environment is the principal cause of the adaptedness of form, and the determinant of what it is to be an adaptation. I argue that this conception of the environment neither adequately explains (...) nor individuates evolutionary adaptations. Instead, adaptation, properly construed, is an evolutionary response to affordances. The environment, traditionally construed, underdetermines an organism’s affordances. Instead, I argue that the environment takes its place in evolutionary models not as a discrete causal entity, but as an abstraction. (shrink)

In evolutionary biology changes in population structure are explained by citing trait fitness distribution. I distinguish three interpretations of fitness explanations—the Two‐Factor Model, the Single‐Factor Model, and the Statistical Interpretation—and argue for the last of these. These interpretations differ in their degrees of causal commitment. The first two hold that trait fitness distribution causes population change. Trait fitness explanations, according to these interpretations, are causal explanations. The last maintains that trait fitness distribution correlates with population change but does not cause (...) it. My defense of the Statistical Interpretation relies on a distinctive feature of causation. Causes conform to the Sure Thing Principle. Trait fitness distributions, I argue, do not. *Received July 2009; revised October 2009. †To contact the author, please write to: Department of Philosophy/Institute for the History, Philosophy of Science and Technology, University of Toronto, Victoria College, 91 Charles Street West, Toronto, ON M5S 1K7, Canada; e‐mail: [email protected]. (shrink)

The royal house of Pontus claimed to be descended from the cream of the old Persian nobility, the Seven Families, and to have received its lands as the gift of Darius I. The claim is first attested by Polybius, and it became common currency in the reign of Mithridates Eupator. Since Théodore Reinach wrote his magisterial history of the Pontic kingdom, the royal pretensions of the regime have been dismissed as apocryphal.

Much recent research has sought to uncover the neural basis of moral judgment. However, it has remained unclear whether "moral judgments" are sufficiently homogenous to be studied scientifically as a unified category. We tested this assumption by using fMRI to examine the neural correlates of moral judgments within three moral areas: (physical) harm, dishonesty, and (sexual) disgust. We found that the judgment ofmoral wrongness was subserved by distinct neural systems for each of the different moral areas and that these differences (...) were much more robust than differences in wrongness judgments within a moral area. Dishonest, disgusting, and harmful moral transgression recruited networks of brain regions associated with mentalizing, affective processing, and action understanding, respectively. Dorsal medial pFC was the only region activated by all scenarios judged to be morally wrong in comparison with neutral scenarios. However, this region was also activated by dishonest and harmful scenarios judged not to be morally wrong, suggestive of a domain-general role that is neither peculiar to nor predictive of moral decisions. These results suggest that moral judgment is not a wholly unified faculty in the human brain, but rather, instantiated in dissociable neural systems that are engaged differentially depending on the type of transgression being judged. (shrink)

According to a prominent view of evolutionary theory, natural selection and the processes of development compete for explanatory relevance. Natural selection theory explains the evolution of biological form insofar as it is adaptive. Development is relevant to the explanation of form only insofar as it constrains the adaptation-promoting effects of selection. I argue that this view of evolutionary theory is erroneous. I outline an alternative, according to which natural selection explains adaptive evolution by appeal to the statistical structure of populations, (...) and development explains the causes of adaptive evolution at the level of individuals. Only together can a statistical theory of selection and a mechanical theory of development explain why populations of organisms comprise individuals that are adapted to their conditions of existence. (shrink)

Psychological individualism is motivated by two taxonomic principles: (i) that psychological states are individuated by their causal powers, and (ii) that causal powers supervene upon intrinsic physiological state. I distinguish two interpretations of individualism--the 'orthodox' and the 'alternative'--each of which is consistent with these motivating principles. I argue that the alternative interpretation is legitimately individualistic on the grounds that it accurately reflects the actual taxonomic practices of bona fide individualistic sciences. The classification of homeobox genes in developmental genetics provides an (...) illustration. When applied to the taxonomy of psychological kinds, alternative individualism has some surprising consequences. In particular, externalist taxonomies of thought are consistent with the alternative interpretation, and hence consistent with individualism. I conclude, on this basis, that the individualism/externalism dispute which has long preoccupied philosophy of psychology is an empty one. (shrink)

Each target article contributes important proto-musical building blocks that constrain music as-we-know-it. However, neither the credible signaling nor social bonding accounts elucidate the central mystery of why music sounds the way it does. Getting there requires working out how proto-musical building blocks combine and interact to create the complex, rich, and affecting music humans create and enjoy.

This collection addresses fundamental themes in Marx's social and political thought. It covers key controversies in the analysis of Marx's overall intellectual development, the influence of Hegel, the Marx-Engels relationship, the validity of historical materialism, the significance of class and class struggle, the state and political parties, and reform and revolution. It also addresses Marx's work as historian, anthropologist, student of time and space, social psychologist, social interactionist, and literary scholar. It also covers debates regarding Marx's views on technological determinism: (...) *national identity *nationalism, and cosmopolitanism *cities and citizenship *welfare and human rights *science and ideology *patriarchy and the family *gender and sexual orientations *culture and religion *alienation and fetishism *justice in capitalism and communism. Bob Jessop provides an extended general introduction and also summarizes and interrelates the various articles at the start of each volume. Contributors adopt a wide range of approaches and cover some sixty years of analysis. (shrink)