The mechanics of evolution are measured in generations. With each generation, there may be a slight mutation, not always one that can be measured, and not always one that is visibly applicable to the process of evolution. However, slight mutations there are, because of the imperfection of DNA reproduction, and a competitive selection process there is, both in logic and in evidence. If there is a trend towards a certain direction, these distinctive products can be called subspecies. Scientists have set a high bar, however, for the definition of species, which is something which can reproduce with itself, but not with another different species. Given the short history of the scientific process, is it surprising that we have not yet observed, under laboratory conditions, something which takes so long to happen?
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