How Lucky We Are To Exist

The story below about my great-grandmother has a certain "Holy Crap" quality to it. Shari mentioned in the comments that it is by pure luck that any of us happened to be. In that vein, I'm now going to plagiarize my favorite passage from Bill Bryson's book A Short History of Nearly Everything. It was what I was thinking about when I selected that story, since I knew I wanted to write about Viola, but had planned on talking about the things I inherited from her. But then the digital camera battery was dead, and it wouldn't have worked as well.

The average species on Earth lasts for only about four million
years, so if you wish to be around for billions of years, you must be as
fickle as the atoms that made you. You must be prepared to change everything about yourself -- shape, size, color, species affiliation, everything -- and to do so repeatedly. That's much easier said than done, becuse the process of change is random. To get from "protoplasmal primordial atomic globule" (as Gilbert and Sullivan put it) to sentient upright modern human has required you to mutate new traits over and over in a precisely timely manner for an exceedingly long while. So at various periods over the last 3.8 billion years you have abhorred oxygen and then doted on it, rown fins and limbs and jaunty sails, laid eggs, flicked the air with a forked tongue, een sleek,, been furry, lived underground, lived in trees, been as big as a deer and as small as a mouse, and a million things more. The tiniest deviation from any o tese evolutionary shifts, and you might now be licking algae from cave walls or lolling walruslike on some stony shore or
disgorging air through a blowhole in the top of your head before diving sixty feet for a mouthful of delicious sandworms.

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 -- forturnate 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 forbear on both sides has been attractive enough to find a mate, healthy enough to reproduce, and sufficiently blessed by fate and
circumstance to live long enough to do so. Not one of your pertinent ancestors was squashed, devoured, drowned, starved, stranded, 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 in order to perpetuate the only possble sequence of hereditary combinations that could result -- eventually, astoundingly, and all too briefly -- in you.