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Evolution and Optimum Seeking

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102 R<strong>and</strong>om Strategies<br />

(1972), <strong>and</strong> Papentin (1972) are so di erent in emphasis that they are not applicable to<br />

the kind of problems considered here. The ways in which a process of mathematization<br />

can be implemented in theoretical biology are documented in for example the books by<br />

Waddington (1968) <strong>and</strong> Locker (1973), whichcontain a number of contributions of interest<br />

from the optimization point of view, as well as many articles in the journal Mathematical<br />

Biosciences, which has been published by R. W. Bellman since 1967, <strong>and</strong> some papers<br />

from two Berkeley symposia (LeCam <strong>and</strong> Neyman, 1967 LeCam, Neyman, <strong>and</strong> Scott,<br />

1972). Whereas many modern books on biology, such as Riedl (1976) <strong>and</strong> Roughgarden<br />

(1979), still give mainlyverbal explanations of organic evolution, in general, this is no<br />

longer the case. Physicists like Ebeling <strong>and</strong> Feistel (see Feistel <strong>and</strong> Ebeling, 1989) <strong>and</strong><br />

biologists like Maynard Smith (1982, 1989) meanwhile have contributed mathematical<br />

models. The following two paragraphs thus no longer represent the actual situation, but<br />

before we add some new aspects they will be presented, nevertheless, to characterize the<br />

situation as perceived by the author in the early 1970s (Schwefel, 1975a):<br />

Relationships have been seen between r<strong>and</strong>om strategies <strong>and</strong> biological evolution<br />

on the one h<strong>and</strong> <strong>and</strong> the psychology of recognition processes on the other,<br />

for example, by Campbell (1960) <strong>and</strong> Khovanov (1967). The imitation of such<br />

processes{the catch phrase is arti cial intelligence{always leads to the problem<br />

of choosing or designing a suitable search algorithm, which should rather<br />

be heuristic than strictly deterministic. Their simplicity, reliability (even in<br />

extreme, unfamiliar situations), <strong>and</strong> exibility give the r<strong>and</strong>om strategies a<br />

special r^ole in this eld. The topic will not be discussed more fully here, except<br />

to mention some publications that explicitly deal with the relationship<br />

to optimization strategies: Friedberg (1958), Friedberg, Dunham, <strong>and</strong> North<br />

(1959), Minsky (1961), Samuel (1963), J. L. Barnes (1965), Vagin <strong>and</strong> Rudelson<br />

(1968), Thom (1969), Minot (1969), Ivakhnenko (1970), Michie (1971),<br />

<strong>and</strong> Slagle (1972). A particularly impressive example is given by the work of<br />

Fogel, Owens, <strong>and</strong> Walsh (1965, 1966a,b), in which imitation of the biological<br />

evolutionary principles of mutation <strong>and</strong> selection gives a (mathematical)<br />

automaton the ability to recognize prescribed sequences of numbers.<br />

It may be that in order to match the capabilities of the human brain{<strong>and</strong><br />

to underst<strong>and</strong> them{there must be a move away from the digital methods of<br />

present serial computers to quite di erent kinds of switching elements <strong>and</strong><br />

coupling principles. Such concepts, as pursued in neurocybernetics <strong>and</strong> neurobionics,<br />

are described, for example, by Brajnes <strong>and</strong> Svecinskij (1971). The<br />

developmentoftheperceptron by Rosenblatt (1958) can be seen as a rst step<br />

in this direction.<br />

Two research teams that have emphasized the adaptive capacity ofevolutionary procedures<br />

<strong>and</strong> who have shown interesting computer simulations are Allen <strong>and</strong> McGlade<br />

(1986), <strong>and</strong> Galar, Kwasnicka, <strong>and</strong> Kwasnicki (see Galar, Kwasnicka, <strong>and</strong> Kwasnicki,<br />

1980 Galar, 1994). In terms of the optimization tasks looked at throughout this book,<br />

one might call their point of view dynamic or on-line optimization, including optimum<br />

holding against environmental changes. As Schwefel <strong>and</strong> Kursawe (1992)have pointed

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