Don't you know that 'big' hair is a genetic trait of redneck Southern women, especially those who host programs on Christian broadcasting networks! Sheesh!! (LOL in case anyone thinks I'm serious).
The so-called "hairy" Ainu were given the name because they have abundant body hair like some Europeans and often have long, flowing beards in contrast to the Japanese people. If they're the "hairiest people on earth" I haven't been able to find a citation to that effect. Here's a comment from a site I just located:
"The Ainu are somewhat taller than the Japanese, stoutly built, well proportioned, with dark-brown eyes, high cheek-bones, short broad noses and faces lacking length. The hairiness of the Ainu has been much exaggerated. They are not more hairy than many Europeans. Never shaving after a certain age, the men have full beards and moustaches, but the stories of Ainu covered with hair like a bear are quite unjustified by facts. Men and women alike cut their hair level with the shoulders at the sides of the head, but trim it semicircularly behind."
Their origin is indeed mysterious but there's abundant evidence that shows they've been in the Japanese islands much longer than the Japanese themselves. Hokkaido and Honshu have many Ainu place names. Even the sacred volcano Fujiyama, is named for their fire goddess Fuji.
Ainu definitely have skins as light as Europeans and lack the Mongoloid epicanthic eyefold which gives Asians the appearance of slanted eyes. Yet to date no one knows where they came from originally. Their language is unlike any other and contains no clues so far as I can tell. DNA tests will probably tell the story some day. Some experts say they definitely have Mongoloid origins but it's unknown whether they may have Caucasoid genes.
Then there's WWF's George "The Animal Steele". You couldn't see his back at all.