Emergent phenomena11/3/2022 One of them, at random, sends out a chemotactic signal. Hopefully by understanding the simplest, we can describe features common to all emergent phenomena.Īggregation starts when amoebae are starved. The second is the behavior of the aggregated mass as a single multi-celled organism. The first is aggregation of previously independent amoebae into one large mass of densely packed cells. The development of slime molds requires two emergent phenomena. To further understand spontaneous self-organization it is instructive to examine a simple system, the formation of slime molds. Such autocatalytic sets have now been created in the laboratory ( 7). With further diversity of different peptides, the ratio of reactions to molecules increases until suddenly “a giant catalyzed reaction web forms” in which the original peptide reproduces itself spontaneously. Subsequently, Kauffman ( 9, 10) showed that in an ensemble of peptides, as the number of different peptides increases, the probability of one catalyzing the reaction between others to synthesize a new peptide becomes a virtual certainty. Nonlinearity allows systems to explore new domains and what develops can only be predicted as probabilities, not certainties. In the spontaneous development of order, Prigogine and Stengers ( 15) emphasized the importance of non-linear feedforward loops by which a molecule catalyzed itself. Life requires non-equilibrium thermodynamics. It is only when we die and stop importing energy that we obey the second law, with its inevitable decay into thermodynamic equilibrium when every chemical reaction goes equally in both directions, no thermal gradients exist, and all forces acting on us cancel so that movement is impossible. This is how eons of Darwinian evolution and much shorter gestational times for fetal development create the stunning order of life. Thus the imported energy is used to create the spontaneous development of self-organized, emergent phenomena. As entropy decreases, order must increase. Entropy in the form of waste products is exported. The second law only applies to closed thermodynamic systems with no exchange of energy or entropy with the environment, whereas life is an open thermodynamic system, in which energy is imported as food and oxygen and utilized in a process we call metabolism. Ilya Prigogine won the Nobel Prize for discovering that the importation and dissipation of energy into chemical systems could reverse the inexorable disintegration into disorder predicted by the second law ( 15). It takes energy to create improbable configurations from disordered ones. This process is irreversible left to itself, the improbable doughnut never spontaneously reforms. When dispersion is complete, entropy is maximal. With time, the order disappears as the smoke particles diffuse and become randomly dispersed throughout the room. When it emerges from a smoker's mouth it is in a highly ordered, improbable configuration. Order is improbable and disorder (called entropy) is more probable. It states that systems tend to evolve from improbable configurations to more probable ones. Understanding starts with the second law of thermodynamics because it is the only physical law dealing with order. But to understand emergence it is better to start with simpler examples and, once they are solved, to progress to more complex ones. Reductionism cannot solve the secrets of emergence.Ĭonsciousness is the most striking (and difficult) example of an emergent phenomenon. Thus understanding emergence requires studying the behavior of integrated networks. Life provides many interconnections: hormones, nerves, gap junctions, cytokines, and so forth. And for the component parts to self-organize, they must intercommunicate, interact, and cooperate. Ensembles mean that an emergent system is composed of many parts. Spontaneity and self-organization mean that no external agent is sculpting the organism: it sculpts itself. These I define as the spontaneous development of self-organized order among ensembles that can neither be predicted nor explained by examining component parts in isolation. Life's order is characterized by emergent phenomena. If we fail to do so, physiology will become a science secondary to biochemistry and biophysics. It is physiology's job to provide a deep understanding of life, not merely a description. Biochemistry and biophysics responded to the first challenge with stunning success, resulting in today's revolution in genetics and molecular biology. In his monograph “What Is Life?” ( 18), he stated that life had two secrets: the passage of an encoded molecule from parents to offspring to explain heritable characteristics, and the spontaneous emergence of self-organized order. In 1944 erwin schrodinger, the Nobelist in physics, presented biology with an unprecedented challenge.
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