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1.
Prog Biophys Mol Biol ; 113(1): 57-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23562916

RESUMO

This paper attempts to suggest a more 'natural' mode of computation; one that can fail if carried out too long, and that might be deployed differently in different contexts. The developmental process of dissipative structures is brought to bear on this question, as well as hierarchical structures.


Assuntos
Algoritmos , Biofísica/métodos , Simulação por Computador , Matemática , Modelos Biológicos , Biologia Molecular/métodos , Biologia de Sistemas/métodos , Integração de Sistemas
2.
Biosystems ; 103(3): 315-30, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21055440

RESUMO

Many problems in evolutionary theory are cast in dyadic terms, such as the polar oppositions of organism and environment. We argue that a triadic conceptual structure offers an alternative perspective under which the information generating role of evolution as a physical process can be analyzed, and propose a new diagrammatic approach. Peirce's natural philosophy was deeply influenced by his reception of both Darwin's theory and thermodynamics. Thus, we elaborate on a new synthesis which puts together his theory of signs and modern Maximum Entropy approaches to evolution in a process discourse. Following recent contributions to the naturalization of Peircean semiosis, pointing towards 'physiosemiosis' or 'pansemiosis', we show that triadic structures involve the conjunction of three different kinds of causality, efficient, formal and final. In this, we accommodate the state-centered thermodynamic framework to a process approach. We apply this on Ulanowicz's analysis of autocatalytic cycles as primordial patterns of life. This paves the way for a semiotic view of thermodynamics which is built on the idea that Peircean interpretants are systems of physical inference devices evolving under natural selection. In this view, the principles of Maximum Entropy, Maximum Power, and Maximum Entropy Production work together to drive the emergence of information carrying structures, which at the same time maximize information capacity as well as the gradients of energy flows, such that ultimately, contrary to Schrödinger's seminal contribution, the evolutionary process is seen to be a physical expression of the Second Law.


Assuntos
Evolução Biológica , Modelos Biológicos , Termodinâmica , Entropia , Filosofia , Seleção Genética , Simbolismo
3.
Artif Life ; 14(3): 363-74, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18631102

RESUMO

Structural complexity characterizes our representations of dissipative structures. As a mechanistic concept, when referred to natural systems it generates perplexity in the face of logically sound models. Natural selection is a simple mechanistic concept, whose logic is well exemplified in genetic algorithms. While biological traits and functions do appear to have been subjected to selective culling, current neo-Darwinian theory is unable to account for the evolution of traits or functions when many of these are taken as the separate objects of independent fitness functions. Soft selection, acting in a phenotypically holistic manner, does model selection acting upon structurally complex systems with many traits and functions, but does not account for the evolution of specific traits or functions. It is further suggested that selection cannot be other than a weak force in the early, generative stages of complex life histories, and that this is a good thing, preserving their generativity. I conclude that natural selection theory by itself cannot account for increases in structural complexity.


Assuntos
Seleção Genética , Algoritmos , Animais , Inteligência Artificial , Evolução Biológica , Simulação por Computador , Meio Ambiente , Humanos , Modelos Biológicos , Modelos Genéticos , Modelos Teóricos , Fenótipo , Biologia de Sistemas , Fatores de Tempo
4.
Biosystems ; 92(3): 233-44, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18448239

RESUMO

Ecological boundaries have been described as being multiscalar or hierarchical entities. However, the concept of the ecological boundary has not been explicitly examined in the context of hierarchy theory. We explore how ecological boundaries might be envisioned as constituents of scalar hierarchical systems. Boundaries may be represented by the surfaces of constituents or as constituents themselves. Where surfaces would correspond to abrupt transition zones, boundary systems might be quite varied depending on hierarchical context. We conclude that hierarchy theory is compatible with a functional vision of ecological boundaries where functions can be largely represented as the processing or filtering of ecological signals. Furthermore, we postulate that emergent ecological boundaries that arise on a new hierarchical level may contribute to the overconnectedness of mature ecosystems. Nevertheless, a thermodynamic approach to the emergence and development of boundary systems does indicate that in many situations, ecological boundaries would persist in time by contributing to the energy production of higher hierarchical levels.


Assuntos
Ecologia , Modelos Biológicos , Software , Termodinâmica
5.
Evolution ; 31(4): 737-749, 1977 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28563705
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