Natural selection adaptations

Let several "populations" of autocatalysts (a = 1, 2,. ..) that are generated by the same "food" R function simultaneously in the system. A decrease in R to the value R results in the complete "extinction" of those autocatalysts for which Rcra = 82a/sia < R. If the amount (concentration) of "food" then increases (i.e., if R rises), the populations of the extinct autocatalysts do not restore because of the disappearance of the respective autocatalyst inoculants. However, if the autocatalysts are capable of mutating toward a decrease in critical parameter Rcra, the inoculants of the autocatalysts with minimal R a can persist even at the reduced concentration of food. For this reason, the population of these selected autocatalysts will start growing with the increase in R, if any. In other words, an analogue of natural selection adapts the autocatalyst system to the conditions of "starvation in "food" R. 

Because not all individuals in a population survive and reproduce equally well in a particular environment, some individuals contribute more offspring to subsequent generations than do other individuals. Such differential contribution of offspring resulting from variations in heritable traits was called natural selection by Charles Darwin. Natural selection is especially important because it is the only evolutionary agent that adapts organisms to their environments. 

Although natural selection is the only evolutionary agent that adapts organisms to their environments, the course of evolution has been profoundly influenced by major environmental changes, some of which had catastrophic effects. Some of these events resulted from Earth s internal processes, such as the activity of volcanoes and the shifting and colliding of continents. Others were the result of external events, such as collision of meteorites with Earth. 

Consider the first alternative, that (R) is not complete, either because some disjuncts haven t occurred yet or perhaps that there is an indefinite number of possible macromolecular implementations for (PS). This, in fact, seems to me to be true, just by virtue of the fact that natural selection is continually searching the space of alternative adaptations and counteradaptations, and that threats to the integrity and effectiveness of meiosis might in the future result in new macromolecular implementations of (PS) being selected for. However, this is no concession to antireductionism. It is part of an argument that neither (PS) nor (G) report an explanatory generalization, that they are in fact temporarily true claims about local conditions on the Earth. 

Here, past events help to explain current events via implicit principles of natural selection. Such ultimate explanations have been famously criticized as just-so stories, too easy to frame and too difficult to test (Gould and Lewontin, 1979). There is certainly something to this charge. Just because available data or even experience shows that eyespots are widespread does not guarantee that they are adaptive now. Even if they are adaptive now, this is by itself insufficient grounds to claim they were selected because they were the best available adaptation for camouflage, as opposed to some other function, or for that matter that they were not selected at all but... 

A core assumption of ultra-Darwinism is that if not all, then most observed characters must be adaptive, so as to provide the phenotypic material upon which natural selection can act. However, what constitutes a character - and what constitutes an adaptation - is as much in the eye of the beholder as in the organism that is beheld, as Gould and Lewontin pointed out in their famous paper on spandrels (Gould and Lewontin, 1979). Natural selection s continual scrutiny does not give it an a la carte freedom to accept or reject genotypic or phenotypic variation. Structural constraints insist that evolutionary, genetic mechanisms are not infinitely flexible but must work within the limits of what is physically or chemically possible (for instance, the limits to the size of a single cell occasioned by the physics of diffusion processes, the size of a crustacean like a lobster or crab by the constraints... 

Dyson s model has been the subject of careful criticism as well as well-meaning agreement. Shneior Lifson (1997) found fault in particular with Dyson s assumption that metabolism (and other properties) could have developed without natural selection. In his third assumption, Dyson postulates that There is no Darwinian selection. Evolution of a molecule population occurs via genetic drift (Dyson, 1999). Lifson (1997) points out that, while Dyson stresses the role of primitive metabolism, its adaptability, error tolerance etc., he himself considers that such properties can only evolve via natural selection. 

Evolution by natural selection was first explained by Charles Darwin in his book On ttie Origin of Species (1859). Briefly stated, the theory suggests that evolution occurs through heritable propagation of adaptive traits. Nature produces a large variation in the traits of organisms. Those traits that are in some way adaptive, increasing the survival and... 

Such a strong impact on survivorship or fecundity, and on the fitness of individuals, means exerting strong natural selection on herbivorous insects. This should favor the rapid evolution of insect adaptations which overcome it. This is, of course, a common occurrence in the application of pesticides or the development of resistant crop plant cultivars (11). The supposition that plant defenses select for detoxication adaptations in insects is the foundation of the concept of coevolution (12). 

A genetic algorithm is an adaptation procedure based on natural selection and genetics. 

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