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If Humans Die Out, Octopuses Already Have the Chops to Build the Next Civilization, Scientist Claims
(www.popularmechanics.com)
Do we need to die for this to happen? 
It's real sad to me how all the other intelligent lifeforms on this planet are biologically limited in one way or another. Rats? Live a few years. Octopi? Live a few years. Dolphins? The fuck they gonna do with those flippers? Ravens? Ditto, but wings. They can't even masturbate. Humans hit the evolutionary jackpot.
I think the raven's bigger problem is that they are just too weak. Humans aren't very strong by animal standards but we are strong enough to break wood and rocks. How would a raven ever get past the stone age. You'd need an entire flock of ravens with stone axes to fell a tree.
To be fair, I feel like ravens would probably need a lot less wood than humans do, so branches & young trees would likely suffice.