It was also developed “iteratively” under extremely harsh selection criteria over a time scale that is so long it is almost impossible to reason about. An old geology textbook I had used the analogy of a geologic timeline that stretched from LA to NYC. Life appears really early (in CA somewhere IIRC) and human existence is about the width of a crack in the pavement just before you hit the Atlantic Ocean.

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zmgsabst 10 hours ago | parent [-]

Using a timeline from LA to NYC, since you made me curious:

- life formed 3.7B of 4.5B years ago, which is 700km towards NYC from LA; or about Colorado

- proto-humans formed 2M of 4500M years ago, which is about 1.7km “from” NYC; a distance hard to compare with the whole way

- human lifespans are about 70 of 4.5B years, which is about 6cm “from” NYC; a distance hard to compare with either 1.7km, 700km for life to form, or the whole 3966km.

	▲	cogogo 6 hours ago \| parent [-]
		Ha! thanks! My memory of this was way off. But I guess I liked the idea at the time if I remembered it at all decades later. Life has been evolving for a LONG time.