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Similarly, I have a number from the back of the envelope in my back pocket that roughly 2.2 trillion person-years have been lived (by modern humans), roughly on
by saalweachter 4y ago
Similarly, I have a number from the back of the envelope in my back pocket that roughly 2.2 trillion person-years have been lived (by modern humans), roughly one third before agriculture and one third after the industrial revolution.
World War 2 was roughly one percent of history, weighted by person-years.
- jbaber 4y agoWhat interval is the remaining third?
- Infernal 4y agoUnless I'm misunderstanding, the remaining third would be between the advent of agriculture and the industrial revolution.
- 988747 4y agoSo the first third took millions of years, second third took roughly 6-7k years, and the last third took 200 years?
- tomjakubowski 4y agoLike everything on the prehistoric timeline, the dawn of agriculture keeps getting pushed back. I think that's believed to be older than 10k years ago now.
- Tuna-Fish 4y agoWith the caveat that the intensity of the increasingly older agriculture is increasingly low. There are clearly agricultural societies, where >90% of calories come from cultured plants, and there are clearly hunter-gatherer societies that predate them, where ~0% do. We used to believe in a relatively sharp cutoff between these, where once people learned to grow food, they quickly moved to mostly grow their food. This is no longer thought to be the truth, and there was likely a "transitional period" of many thousands of years as people very slowly hunted and gathered less and planted more. (Why believe in a sharp transition? Because there is a lot of archeological evidence for it, so it clearly happened in lots of places. It's just that this doesn't represent people inventing agriculture, but it spreading to a new area and displacing older lifestyles, either by migrations of people or of ideas.)
- saalweachter 4y agoThe first is only hundreds of thousands, starting with anatomically modern humans and not all of our precursors who lived for millions of years before that. Though that may not change much -- depending on your estimates, Neanderthals probably spanned 3-30 billion person-years, as little as 0.1% of modern humans. All human precursors (5-10My worth) might be margin of error on the modern humans' totals. On the other end of things, if we plateau at around 10 billion humans, it will only take about 75 years to accumulate the next third (well, quarter) of human existence.
- OkayPhysicist 4y agoMy favorite framing of that is that in homo sapiens, life has only been proven to have a mortality rate of 93%.
- pavlov 4y agoMy personal mortality rate is 0% so far. Not sure what the fuss is about.
- andrewmutz 4y ago> World War 2 was roughly one percent of history, weighted by person-years. Do you mean history since WW2 has been about one percent of history?
- saalweachter 4y agoThe population during the ~decade WWII covered was 2.3 billion, so about 23 billion person-years were lived, about 1% of the total. You can argue that total down considerably -- other stuff happened during that decade, and while something like 10% of the population fought in the war, it wasn't truly global -- but it's still impressive on the scale of history. The US Revolutionary War was probably only 1/1000th of that.