Pleistocene Epoch: Facts About the Last Ice Age (LiveScience)
"There have been at least five documented major ice ages during the 4.6 billion years since the Earth was formed - and most likely many more before humans came on the scene about 2.3 million years ago. The Pleistocene Epoch is the first in which Homo sapiens evolved, and by the end of the epoch humans could be found in nearly every part of the planet."
Winter Is Coming, So Why Not Get Yourself A Real Life Dire Wolf? (IO9)
"The Dire Wolf Project, started by the American Alsatian Breeders Association, is trying to breed new dire wolf-like dogs - not genetically identical to their forebears, of course, but a large, somewhat shaggy canine that looks like the dire wolves of old, but is still domesticated and calm."
Dire Wolf: Taxonomy and Nomenclature (San Diego Zoo)
"Two extinct dire wolf subspecies probably exist based on clear size differences and earlier appearance of eastern subspecies. The modern Canid family originated in North America diverging into many species beginning about 10 million years ago (Miocene) from ancestral dogs."