As a way of getting around, flying has a lot to offer. …Only three kinds of creatures that exist in the modern world have evolved as true flyers: birds, insects, and bats. But the benefits of flight are huge, and dozens of living things have evolved ways to get some of those advantages for themselves.  …With its big dark eyes and round ears, our own Northern flying squirrel (Glaucomys sabrinus macrotis) is about the cutest of such “flying” animals. …Once a common sight in the northern tier of Pennsylvania, the Northern flying squirrel is now endangered in our state (although it is secure nationally). A detailed survey from 2003 – 2007 found only 33 individuals, all but two of them in the Poconos.Habitat destruction is the culprit.The rich old-growth hemlock and spruce forests that once swept across Pennsylvania have been lost to development, or reduced to small fragments.