In the ultimate canine ancestral story, National Geographic explores the genetic journey from wolf to dog. Travel back 100,000 years to meet the "mother of all dogs" and trace the evolution of her descendents over the eons, even as we evolved ourselves - from cave dwellers to modern humans. Find out what scientists are learning about dogs' unique ability to communicate with humans, and how powerful brain chemicals work to cement our affection for each other. Delve into the history of selective breeding and see how man created dogs to serve our needs as laborers, companions, hunters, herders, and warriors, as well as to suit our aesthetic fancy.  From immense Great Danes and diminutive Chihuahuas to curly-haired poodles and streamlined greyhounds - it's no coincidence that dogs are in fact the most diverse mammals on the planet.This product is manufactured on demand using DVD-R recordable media. Amazon.com's standard return policy will apply.This product is expected to play back in DVD Video "play only" devices, and may not play in other DVD devices, including recorders and PC drives.