drones = trilobite/crabs zerglings = frog/lizard/raptors hydralisks = mantis/cobras defilers = silverfish/centipedes ultralisks = mammoths lurkers = ?? etc., etc.
Lurkers are like those underground spiders that make a hole and pop up when they feel movement on the surface. Lol now all they need is to shoot spikes through the ground.
Hydralisks are more like those dinosaurs that opened their "ears" and shot thingys in the jurassic park video games Mutalsisks are more like flying cobras
zerglings are birds without wings. Pinguins anyone? LOL (a T-rex, just much smaller) dragons are hmm eagle? defiler is lizzard lurkers are those spiders who dig into the sand and attack people who come across them http://www.youtube.com/watch?v=PuPStWFnHmY Infested terran are people who has succombed to the overmind Overlords are like flying blue whales. The blue whales can fly because they carry light weighted gas inside of them. broodlings are like a 24 hour fly, just they cant fly. parasite counts as a unit?
