Considering that there are a billion times more copies of bacterial genes than any other, I'd say that "upwards" isn't a better way to propogate the gene: http:

Considering that there are a billion times more copies of bacterial genes than any other, I'd say that "upwards" isn't a better way to propogate the gene: http://www.stephenjaygould.org/library/gould_bacteria.html http://www.stephenjaygould.org/library/gould_bacteria.html