It seems like there's a whole lot of nothing going on for the first 2 billion years. But what I think we miss is during that time, a lot of the complex biochemical and organic pathways were being developed--without which none of the other classifications of lifeforms would have appeared--and none of these bio pathways manifest themselves in the fossile record.
If we were somehow able to classify organisms biochemically instead of by their physical features, I wonder how different the picture would look?
That's true, many of those pathways are shared between all current species, so they must have evolved in that early period. I wonder how (for lack of a better word) inefficient organisms must have been before they evolved the modern citric acid cycle, for example.
This has always been the best explanation of why we don't see evidence of aliens. Any detectable species is less than a pixel on that timescale. Combined with likelyhood of getting wiped out by natural (comet/asteroid) or technological(nuke, pollution/climate, custom disease, etc).
I think this timeline tells a different story: Intelligent life is very rare. Typically, life doesn't evolve beyond single-celled or primitive multi-celled organisms before the star goes red giant.
The chances of general intelligence evolving are so small that we're probably the first.
Umm... no? Life on Earth started about 4 billion years ago. The universe is about 13 billion years old. Also, earlier stars had lower metallicity, which made it less likely for rocky planets to form. Population I stars (like the sun) are probably the first generation of stars with high enough metallicity to make rocky planets and life likely.
Any anyway, how do you explain going from single-celled creatures to working organisms with a trillion cells? Darwin claims species are driven by their environment to better compete - is that not something like perfecting them?
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[ 5.5 ms ] story [ 46.4 ms ] threadIf we were somehow able to classify organisms biochemically instead of by their physical features, I wonder how different the picture would look?
The chances of general intelligence evolving are so small that we're probably the first.
Calling anything the 'pinnacle' of evolution implies some sort of progress towards perfection. Evolution does not work that way.
You're conflating biological evolution with creationism / 'intelligent design'.
We compete for spaces in a niche, we don't compete to be all round "better".