Many professions and classes give some tracking ability: paladins can sense undead, warlocks can sense demons, hunters can track just about everything, miners can find ore nodes, and so on.
Unfortunately, it’s an all-or-nothing deal, and that’s never made sense to me – from a gameworld logic point of view, and from a usability point of view. If you can track big ogrey footprints and little goblin footprints with your ‘track humanoids’ ability, why can’t you choose to ignore the goblins and only locate the ogres?
And from a usability perspective, nothing’s more frustrating when you’re on a farming round than having your minimap cluttered with dots for things you don’t care about. Ask any herbalist how much fun it is(n’t), scouring Zangarmarsh for felweed only to be constantly stymied by little yellow dots for glowcap all over the place.