Origin of Mutations 
so excessive as to be positively injurious; then 
natural selection will step in and eliminate the 
species. But before this happens, something 
may cause a rearrangement of the biological 
molecules in the fertilised egg, and thus a muta- 
tion may arise, which, so to speak, strikes out a 
new line. 
Finally, on this conception there may be some 
sort of connection between fluctuating variations 
and mutations. We can picture the fluctuating 
variations being piled up, one upon the other, 
until there results a rearrangement of the atoms 
in one or more of the biological molecules which, 
in turn, causes a mutation. 
Occasionally this remodelling, as it were, of 
one biological molecule may affect certain of the 
other molecules, and thus lead to correlated 
mutations. 
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