This article responds to two unresolved and crucial problems of cognitive science: (1) What is actually accomplished by functions of the nervous system that we ordinarily describe in the intentional idiom? and (2) What makes the information processing involved in these functions semantic? It is argued that, contrary to the assumptions of many cognitive theorists, the computational approach does not provide coherent answers to these problems, and that a more promising start would be to fall back on mathematical communication theory (...) and, with the help of evolutionary biology and neurophysiology, to attempt a characterization of the adaptive processes involved in visual perception. Visual representations are explained as patterns of cortical activity that are enabled to focus on objects in the changing visual environment by constantly adjusting to maintain levels of mutual information between pattern and object that are adequate for continuing perceptual control. In these terms, the answer proposed to (1) is that the intentional functions of vision are those involved in the establishment and maintenance of such representations, and to (2) that semantic features are added to the information processes of vision with the focus on objects that these representations accomplish. The article concludes with proposals for extending this account of intentionality to the higher domains of conceptualization and reason, and with speculation about how semantic information-processing might be achieved in mechanical systems. (shrink)

Ecological Psychology and Enactivism both challenge representationist cognitive science, but the two approaches have only begun to engage in dialogue. Further conceptual clarification is required in which differences are as important as common ground. This paper enters the dialogue by focusing on important differences. After a brief account of the parallel histories of Ecological Psychology and Enactivism, we cover incompatibility between them regarding their theories of sensation and perception. First, we show how and why in ecological theory perception is, crucially, (...) not based on sensation. We elucidate this idea by examining the biological roots of work in the two fields, concentrating on Gibson and Varela and Maturana. We expound an ecological critique of any sensation-based approach to perception by detailing two topics: classic retinal image theories and perception in single-celled organisms. The second main point emphasizes the importance of the idea of organism-environment mutuality and its difference from structural coupling of sensations and motor behavior. We point out how ecological - phenomenological methods of inquiry grow out of mutualism and compare Gibson’s idea of visual kinesthesis to Merleau-Ponty’s idea of the lived body. Third, we conclude that Ecological Psychology and varieties of Enactivism are laying down different paths to pursue related goals. Thus, convergence of Ecological Psychology and Enactivism is not possible given their conflicting assumptions, but cross-fertilization is possible and desirable. (shrink)

This paper analyzes community ecologist Charles Elton’s ideas on animal communities, and situates them with respect to the classical opposition between organicist–holistic and individualistic–reductionist ecological views drawn by many historians of ecology. It is argued that Elton espoused a moderate ecological holism, which drew a middle way between the stricter ecological holism advocated by organicist ecologists and the merely aggregationist views advocated by some of their opponents. It is also argued that Elton’s moderate ecological holism resonated with his preference for (...) analogies between ecological communities and human societies over more common ones between communities and individual organisms. I discuss, on the one hand, how the functionalist-interactionist approach to community ecology introduced by Elton entailed a view of ecological communities as more or less self-maintaining functionally organized wholes, and how his ideas on this matter were incorporated into their views by organicist ecologists Frederic Clements, Victor Shelford, and Warder C. Allee et al. On the other hand, I identify some important divergences between Elton’s ecological ideas and those of organicist ecologists. Specifically, I show how Elton’s ideas on species distribution, animal migrations, and ecological succession entailed a view of animal communities as exhibiting a weaker degree of part-whole integration than that attributed to them by Clements and Shelford; and how Elton’s mixed stance on the balance of nature idea and his associated views on community stability attributed to communities a weaker form of self-regulation than that attributed to them by Allee et al. (shrink)

This article offers an analysis of ecologist Charles Elton’s “functional” concept of the niche and of the notion of function implicitly associated with it. It does so in part by situating Elton’s niche concept within the broader context of the “functionalist-interactionist” approach to ecology he introduced, and in relation to his views on the relationship between ecology and evolution. This involves criticizing the common claim that Elton’s idea of species as fulfilling functional roles within ecological communities committed him to an (...) idea of communities as units of selection. While such a claim implicitly attributes to Elton an understanding of function along the lines of the selected-effects theory of function advocated by many biologists and philosophers of biology, Elton’s use of the niche concept, I maintain, involves an understanding of function more along the lines of alternative nonselectionist theories such as the causal-role, goal-contribution, and organizational theories. I also briefly discuss how ecologists after Elton also tend to have typically adopted a nonselectionist understanding of the function concept, similar to his. (shrink)

Optimization models have often been useful in attempting to understand the adaptive significance of behavioral traits. Originally such models were applied to isolated aspects of behavior, such as foraging, mating, or parental behavior. In reality, organisms live in complex, ever-changing environments, and are simultaneously concerned with many behavioral choices and their consequences. This target article describes a dynamic modeling technique that can be used to analyze behavior in a unified way. The technique has been widely used in behavioral studies of (...) insects, fish, birds, mammals, and other organisms. The models use biologically meaningful parameters and variables, and lead to testable predictions. Limitations arise because nature's complexity always exceeds our modeling capacity. (shrink)

This article examines some of the main tenets of competition theory in light of the theory of evolution and the concept of an ecological niche. The principle of competitive exclusion and the related assumption that communities exist at competitive equilibrium - fundamental parts of many competition theories and models - may be violated if non-equilibrium conditions exist in natural communities or are incorporated into competition models. Furthermore, these two basic tenets of competition theory are not compatible with the theory of (...) evolution. Variation in ecologically significant environmental factors and non-equilibrium in population numbers should occur in most natural communities, and such changes have important effects on community relations, niche overlap, and the evolution of ecosystems. Ecologists should view competition as a process occurring within a complexdynamic system, and should be wary of theoretical positions built upon simple laboratory experiments or simplistic mathematical models.In considering the relationship between niche overlap and competition, niche overlap should not be taken as a sufficient condition for competition; many factors may prevent or diminish competition between populations with similar resource utilization patterns. The typically opposing forces of intraspecific and interspecific competition need to be simultaneously considered, for it is the balance between them that in large part determines niche boundaries. (shrink)