1.  Stress and fatigue are the main causes for experiencing déjà vu.

2.  Baby hummingbirds know from birth to poop OUTSIDE of the nest.

3.  The earliest known site of human habitation in North America is a short drive from Pittsburgh.  (???)  It’s an archaeological site called Meadowcroft Rockshelter, and it was discovered in 1955 because of a groundhog hole.  It claims to have evidence of human presence as early as 19,000 years ago.

4.  Wood frogs in Alaska can hold their pee for up to eight months during the region’s long winters.  They relieve themselves once temperatures increase.  The urine actually helps keep them alive while they hibernate, with special microbes in their gut turning it into nitrogen.

5.  The fax machine was invented in 1843 . . . way before the telephone was invented.  The initial patent for a “facsimile machine” was for a “chemical telegram.”