"The equivalent fundamental unit in DNA is the nucleotide base. Since there are 4 possible bases, the information content of each base is equivalent to 2 bits. The common gut bacterium Escherichia coli has a genome of 4 mega-bases or 8 megabits. The crested newt, Triturus cristatus, has 40,000 megabits. The 5,000-fold ratio between crested newt and bacterium is about the same as that between my present computer and my first one. We humans have 5,000 mega-bases or 6,000 megabits. This is 750 times as great as the bacterium (which satisfies our vanity), but what are we to make of the newt trumping us sixfold? We'd like to think that genome size is not strictly proportional to what it does: presumably quite a lot of that newt DNA isn't doing anything. This is certainly true. It is also true of most of our DNA."