Well, there's a bit of a differentiation between civ and race, there, though...
The antman civ, if you were to encounter it, and trade with it, without changes to the way the civs are handled, would never be able to build anything they couldn't build beforehand. If you are trading with that civilization, you could sell them steel weapons, build your forges right next to their villages, let them watch you make the steel, and they would never learn to make steel for themselves.
An antman itself (I believe that most antmen technically have no gender to prevent them from breeding), if it joins your civilization, however, is basically just a dwarf with somewhat different attributes. (Toady really only went into serious detail on the attributes and characteristics of the big five races, so all the foo-men have basically human default stats, so would basically just be slightly smaller humans with funny abilities like flight and swimming.) If they "grow up dwarf", then they aren't much different from a dwarf, as far as things currently stand.
There isn't really anything in the game right now to make ability in most jobs really give any particular races an advantage, with the exception of any race that has a bonus to agility or speed, since that just plain makes you do everything faster. This means that any differences in being a "lesser civ" have to be modeled on the civ side of things. Basically, it would require some sort of trafficking of ideas, and ability for civs to adopt jobs (and clothing styles and other odd things) from other cultures they encouter if they were to show any sort of impact from meeting another civ at all.