Having been bandying around numbers big and small for the past two days, I'll run some more past you that are mind-blowing.
The first and simplest forms of life on earth appeared somewhere around 3.8 billion years ago as the late heavy bombardment came to an end. The appearance of life is a miracle. How we got from 'non-life' to 'life' - the latter being able to reproduce, passing on information to the next generation - science still hasn't determined. It's one thing to pass electricity through a chemical soup to create amino acids, its quite another to make something that can spontaneously breed. Science merely makes educated guesses. But somehow living organisms did emerge, a mere 700,000 or so years after our Planet formed.
Between that earliest life and you are - and here's the mind-blowing fact - trillions of individual ancestors, each one of which must have reproduced successfully. Indeed, an unbroken chain of reproduction links you all the way back to the last universal common ancestor.
Every one of your antecedents managed to dodge death long enough to reproduce. Your bloodline has survived five massive (and numerous smaller) extinction events that killed off most of life on earth - but somehow spared your ancestors.
Evolution was slow - for a billion years there was no change. Then multicellular slowly evolved. A distinction emerged between animals and plant life. Then came the Cambrian Explosion. Over the subsequent aeons, your ancestors transitioned from aquatic to terrestrial life, made it into mammalian form - four-legged at first, then bipedal - with ever-bigger brains and opposing thumbs that could fashion and use simple tools.
Intelligence begat greater intelligence. Once hominids had worked out how to control fire, they learned to cook food; no longer did they have to put in so much effort to chew raw meat. This led to the jaw muscles that girdled the skull becoming weaker and weaker, which in turn allowed the cranial cavity to expand along with an expanding brain.
In time, hunter-gatherers turned into part-time gardeners and later full-time farmers - with agriculture came towns and cities - and with them, civilisation.
Our reality is no longer mud and straw and dust and frequent hunger. Our reality is built - bricks and glass and plastic and steel. No longer do we hunt or farm - we shop. We exchange the fruit of our labour - money - for goods. Those with more money utilise the surplus to display their superior status in our mammalian hierarchy.
OK - so here we now are. Marvel at the miracles that have been present at every stage of your evolutionary path from protozoan life; you sit warm and comfortable (I hope!) and reading these words on a technology that our species has developed with the span of two generations.
But the real marvel - the one that biology - physics - philosophy even - have yet to grasp is central to your reality. Consciousness. I will return to this throughout my Lenten series, for this phenomenon is at the heart of the great mystery of life - and what comes after.
Lent 2022: Day four
The Ego: what is it good for?
Lent 2021: Day four
Would the Universe exist without God
Lent 2020: Day four
Conscious Life after Death
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