"Fungii evolved" - says nothing about presence, only ability for the context.

And the coal being laid down for the next 200 million years of profligacy? Er- the message is: it will be concrete, tarmac (which could be used as fuel) and plastic are the layers they will find.

Tell you what, lets wait for that time and we will see if predicting the future is a viable sport - eh?

Just an outside thought, but (should we achieve) massive amounts of fusion generation means appreciable amounts of alpha particles.
Spots before yer eyes, anyone?