providing she keeps up with my reading speed, she doesn't need to turn over the pages herself. Currently re-reading The Emerald Planet by David Beerling about the contribution plants make to the atmosphere and cycles of various chemical compounds involved in keeping the earth a stable environment in which to live. There have been hiccups, during the Carboniferous Era, oxygen levels went up to 35% which was the cause of large leave plants and very large winged insects. It's a fascinating book full of facts and evidence for how the climate has changed.