How in the world did horses get their hooves? What in the world is the difference between their feet and ours? And when in the world did tiny dog-sized horses roam the earth? Join Guy Raz and Mindy for a little trot through the latest Who, What, When, Where, Why, How and Wow in the world of horse hooves! *And be sure to check out this episodes conversation starters at www.wowintheworld.com !