This reminds me of a bit from the introduction to "A Short History of Nearly Everything", by Bill Bryson. To wit: "Not only have you been lucky enough to be at

This reminds me of a bit from the introduction to "A Short History of Nearly Everything", by Bill Bryson. To wit: "Not only have you been lucky enough to be attached since time immemorial to a favored evolutionary line, but you have also been extremely — make that miraculously — fortunate in your personal ancestry. Consider the fact that for 3.8 billion years, a period of time older than the Earth's mountains and rivers and oceans, every one of your forebears on both sides has been attractive enough to find a mate, healthy enough to reproduce, and sufficiently blessed by fate and circumstances to live long enough to do so. Not one of your pertinent ancestors was squashed, devoured, drowned, starved, stuck fast, untimely wounded or otherwise deflected from its life's quest of delivering a tiny charge of genetic material to the right partner at the right moment to perpetuate the only possible sequence of hereditary combinations that could result — eventually, astoundingly, and all too briefly — in you." That said, the calculation is exactly as meaningful as the Drake Equation: you can plug in wild variations in equally "probable" values for the several steps in the equation, yielding staggeringly divergent end results, all of which mean precisely fuck-all, because nearly every number is little better than a wild-assed guess. It's an interesting thing to think about, certainly, and a great way to remind yourself how stupendously fortunate you are to have been given the incredible, inestimably valuable gift of being, but in the end, it's naught more than sophistry dolled up in an equation that passes muster as well as a 16-year old kid using an fake ID saying he's 35.