If you are using Poser 5, set the Ambient channel in the material to a negative for both. If you are using poser 4, Artist, ProPack, or even 5, you can also download "nostril glow" props from www.runtimeDNA.com in the freestuff section.

thou and I, my friend, can, in the most flunkey world, make, each of us, one non-flunkey, one hero, if we like: that will be two heroes to begin with. (Carlyle)