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If you want an up-to-date, authoritative, useful guide to geological history, you want the International Chronostratigraphic Chart. I'm impressed that this is kept updated and is so well done.
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If you want an up-to-date, authoritative, useful guide to geological history, you want the International Chronostratigraphic Chart. I'm impressed that this is kept updated and is so well done.
This seems like a anthropocentric view of the world. Planets moved immense distances, there were generation after generation of bacteria, mountains rose up and crumbled, seas were made and disappeared again.
A lot happened before we showed up. A lot will happen after we're gone, also.
Humans are special because our constructs are orders of magnitude more complex than anything that came before. Opposable thumbs and large wrinkled brains and a lottery ticket combination of environmental factors allowed us to happen. We're a fundamentally different type of thing than anything that we know of that came before. It isn't an anthropomorphic conceit, it's a matter of physical evidence and computational theory. Nothing else does what human brains do. It's a little silly to dismiss it as somehow not real. It's as real as fusion producing light from the core of a sun, or pulsars blazing with energies that outshine entire galaxies.
If you look at a timeline, you might see:
- 3.5 bya: First prokaryote
- 2.5 bya: FIrst eukaryote
- 0.6 bya: Cambrian explosion
- 0.44 bya: First terrestrial life
All the text you see is about change. But 99.99999...% of that time, there is no such event. We write about and think about the changes, not the vast eons when nothing changes (except excruciatingly gradually). After the Cambrian Explosion, trilobytes multiplied and took over the world, but that was (I'm guessing) over millions years; if you were there, you wouldn't see a vast herd (school?) of them advancing across the landscape one day. Short of a few big extinction events (at least the K/T that killed the dinosaurs), I don't think you would notice any such change at all if you lived at any time in history. But now I'm thinking about whether one of those events could be sudden and dramatic.I think that's an important perspective, but I am not seeing how it applies in this case: We're talking mostly about evolutionary changes. For example, right now evolution is happening but it's unlikely that you or I will ever notice it in our relatively short lifespans. And the chance of an event as big as the first eukaryote or the K/T extinction event (the one that killed the dinosaurs) is very, very tiny.
For around the first billion years of earth's history, there was no life at all (as best we can tell right now) - nada, zilch, 'nothing' happening evolutionarily, for most intents and purposes (afaik).