A common feature of the traditional approaches of both title theories is the assumed presence of many secondary maxima in Sewall-Wright's landscape and of many secondary minima in the potential hypersurfaces of proteins. The former assumption results in assigning a major role to environmental changes (including possible coevolution, as well as isolation) in the evolution from a species to a new one; the latter favors kinetic and thermodynamic behaviors of protein folding which actually are not observed.
In contrast, we find strong evidence for a negligible presence of secondary
maxima or minima in hypersurfaces of homogeneous nature and with a high
number of degrees of freedom: most intermediate 'states' should be saddle
points of various orders, out of which the systems escapes along a normal
mode with low, imaginary frequency. If this is true, protein folding essentially
is a random - walk, slightly 'downward'-biased, negentropy-controlled process,
whereas evolution proceeds from a given species along neutral, low probability
lines in mutation space. Hints on the connectivity between such evolutionarily
neutral islands may be borrowed from the study of 'designability' of protein
folds, either in reality or on simple computer models of proteins