Nose is an alteration of the angle of skull following human skeletal Changes.

http://en.wikipedia.org/wiki/Human_nose

Humans
An article published in the speculative journal Medical Hypotheses suggested that the nose is an alteration of the angle of skull following human skeletal changes due to bipedalism. This changed the shape of the skull base causing, together with change in diet, a knock-on morphological reduction in the relative size of the maxillary and mandible and through this a "squeezing" of the protrusion of the most anterior parts of the face more forward and so increasing nose prominence and modifying its shape.