Well, this is a really long shot. When your memory flings up a story you’ll never forget just because of bits in a description only sorta match its details but memory nonetheless throws it in your face, it happens.
Because, sometimes, memory jumbles details from several different stories, or we wouldn’t have these question boards, eh?
Even more odd, it’s a novel series I haven't read, expanded from the short story I’ll never forget.
I keep wondering how
“Evolution's Shore” by Ian Mcdonald might match a vague title recollection (not quite “Genesis”), and how the the alien life that begins not terraforming, but xenoforming, Earth by changing it an the nanometer level, might match “hyper-evolving”.
Mismatch: it occurs in Kenya, not the Americas.
Mismatch: and since it will keep on changing all living matter on Earth, going to Europe would only delay the inevitable. No escape. It’s worse than The Pods.
“Evolution’s Shore” was titled
"Chaga" outside of the USA. It was part of the
"Chaga Saga" by McDonald.
Why carry on about a novel I haven’t yet read: it is an expansion of McDonald’s unforgettable story “Recording Angel” in the anthology completely about nanotechnology,
"Nanotech" edited by Jack Dann and Gardner Dozois in 2000.
(Which also contains "Blood Music". And yeah I had to answer with this in another long shot on another SF forum.)
The “recording angel” refers to the journalist named Gaby.
It is such a long shot that I only answered because of
(1) the vagaries of memory on the part of those asking “what story is this?” and
(2) the very slight matches walloped my memory with an unforgettable story.