Olfactory system
The part of the brain which deals with olfaction is the rhinencephalon, a small part in the human brain, but much more important in other vertebrates. The piriform cortex is probably the area most closely associated with identifying the odor. The medial amygdala is involved in social functions such as mating and recognising animals of the same species. The entorhinal cortex pairs odors with memories. The exact functions of these higher areas is still being researched.