You might be interested in this book: http://www.worldwithoutus.com/about_book.html http://www.worldwithoutus.com/about_book.html It uses both pre-human condit

You might be interested in this book: http://www.worldwithoutus.com/about_book.html http://www.worldwithoutus.com/about_book.html It uses both pre-human conditions and conditions in places humans have avoided (e.g. Chernobyl) to paint a picture of "What if all the humans disappeared all at once" in both short and long term. One hot nugget: The lower-NYC subways would flood almost immediately, and the streets above them would quickly convert into canals (from saltwater erosion), but the bridges would last longer without maintenance than they would under normal human use (because the biggest damage to the bridges is from road salt).