How did dogs get to be dogs? What do our four legged friends dream about? And - most importantly - are dogs really smiling at us when we think they are? All these questions (and a whole lot more)are answered by our intrepid science reporters, Jeanna and Mindy.
- Dogs diverged from wolves — Canis lupus — at least 20,000 and perhaps as long as 40,000 years ago
- A 14,700-year-old jawbone is the oldest undisputed fossil from a domesticated dog (Canis lupus familiaris)
Mystery #2: What Do Dogs Dream About?
- In 1977, scientists studied 6 pointer dogs, studied electrical brain activity for 24 hours: They spent 44% of time awake; 21% drowsy; 12% in REM sleep; and 23% in the deepest stage of non-REM sleep (slow-wave sleep).
- For whatever reason, the size of the dog may determine the size of the dream. Smaller dogs have more frequent but shorter dream periods; large dogs have less frequent but longer dreams.
Guest editor report with Rafi Letzer: Tibetan Mastiffs Bred with Mountain Wolves to Survive at Super-High Altitudes
- We have a special bond with our dogs and when humans and dogs stare into each other's eyes, both experience a rise in levels of oxytocin
- Very few other animals in the world actually make eye contact with humans