Grasslands are its job! By necessity, not by choice. Today’s horse is indeed the current stage of an evolutionary process devoted to speed: long legs and just a single hoof touching the ground. But its story is one of small, forest-dwelling ancestors who, being less speed-obsessed as in the case of Mesohippus, would instead touch the ground with three toes. As their safe forests disappeared in favor of open grasslands, they were pushed to increase their speed by lengthening their legs and reducing toe support.