This is an important and engrossing book written by a New Yorker columnist who focuses on the environment and climate change.  From her home in Williamstown, Kolbert travels the world to visit important sites doing work on acidification of the oceans, loss of coral reefs, loss of forest biodiversity, invasive species, and both the history as well as the future of extinctions.  Dubbing the current period the Anthropocene because of man’s impact on the earth and the effective recreation of Pangea, Kolbert adds our current period to the five major past extinctions (Ordovician 440 MYA due to glaciation; Late Devonian 350 MYA; End of Permian 250 MYA due to volcanism, Late Triassic 200 MYA, and End Cretaceous 66 MYA due to the meteor which struck the Yucatan). The key to our present period is the rate at which change is occurring, over decades rather than eons, which she describes as ‘running geological history backwards at high speed.”   In all of this catastrophism vs. uniformitarianism debate, the big idea which I have an impossible time keeping in mind is that, as she quotes Jan Zalasiewicz, a stratigrapher from the University of Leicester, “….a hundred million years from now, all that we consider to be great works of man—the sculptures and the libraries, the monuments and the museums, the cities and the factories—will be compressed into a layer of sediment not much thicker than a cigarette paper.”  Great comfort, huh!  (Another pearl is the mnemonic for the geological periods:  Camels Often Sit Down Carefully.  Perhaps Their Joints Creek, representing the Cambrian (540-485), Ordovician (485-443), Silurian(443-419), Devonian (419-359), Carboniferous (359-299), Permian (299-252), Triassic (252-201), Jurassic (201-145), and Cretaceous (145-66).