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Generation N: 0
01234560123456
NabbabbAAccbcb-[0] = 3
NAabbcaNbbbcca-[1] = 2
OcOcaaaNaOabaa-[2] = 4
AaAcccbAbccbbc-[3] = 7
AObbabaAOcaabc-[4] = 7
AAAbaacONOaabc-[5] = 4
AAccbcaNNcbbac-[6] = 6
NOccabaOcbabcc-[7] = 4
NOAcbbbAaNabca-[8] = 2
NacbbacAbccbbc-[9] = 3
...
Generation N: 5 Generation N: 6
01234560123456 01234560123456
AabbabcAOcaabc-[0] = 7
AOAbabacbcaaba-[0] = 7
babbabcAOcaabc-[1] = 7
AabbabcAOcbabc-[1] = 8
AOAacbcOAOcaac-[2] = 6 AabbabcAccaabc-[2] = 7
ANbbabcAOcaabc-[3] = 6 NAAbaacONaaacc-[3] = 4
AOAbabacbcaaba-[4] = 7 AOAbabacbcaaba-[4] = 7
AabcaccAONaabc-[5] = 6 AabbbbcAONaabb-[5] = 6
AOAccbaAbaabbc-[6] = 6 AOAbabacNcabba-[7] = 7
AObcabaAbNcaba-[7] = 6 AOAccbaAbaabbc-[6] = 6
NAAbbacONOacca-[8] = 3 NAAbbacONOacaa-[8] = 4
AONbabacbcaaba-[9] = 5 AObbabaAAcaabc-[9] = 7
Figure 3.12.
An initial population and its later descendants created via mutation in
order to solve the Majority(
a
,
b
,
c
) function problem. The chromosomes encode
sub-ETs linked by OR. Note that none of the later descendants are identical to their
ancestors of the initial population. The perfect solution found in generation 6
(chromosome 1) and one of its putative ancestors (chromosome 0 of generation 5)
are shown in bold. Note that chromosomes 1 and 3 of generation 5 are also good
candidates to be the predecessors of this perfect solution; in both cases, two point
mutations would have occurred during reproduction.
identical sub-ETs, due to the fact that both mutations occurred downstream of
the termination point of ORF
2
. As we have seen, mutations occurring in the
noncoding region of a gene have a neutral effect, as they have no expression in
the “organism” itself. But let's not forget that they play nonetheless an impor-
tant role in evolution, because these noncoding sequences might become
active in the blink of an eye due to the actions of the modification operators
(see a discussion of The Role of Neutrality in Evolution in chapter 12).
