About 386 million years ago, a forest stretched from what is now New York State to Pennsylvania, and part of it got itself fossilized, in a place just discovered
near a Catskillls town called Cairo. The oldest known fossil forest in
the world! (What had been the oldest known before, a few million years
younger, is just a few miles away, also in New York.) The trees were not like ours today but closer to tree ferns, one with a conifer-like trunk, and reproduced by spores rather than seeds. Remarkable are their extensive root systems - one is 11 meters across! It is these long-lived woody roots, with multiple levels of branching and small, short-lived perpendicular feeder roots, that transformed the interactions of plants and soils and were therefore pivotal to the co-evolution of forests and the atmosphere
Long long before the human story began but indispensable to that story, since it was the scaling up of carbon dioxide processing effected by trees' verticality which made an atmosphere hospitable to animal life.
