Normal and abnormal development of the antennal lobes in M. sexta
Behaviors critical to survival and reproduction are supported by the sense of smell in Manduca sexta males and females. Females use odor cues to locate and identify acceptable plants on which lay their eggs, and males use female emitted sex-pheromones to locate the female for mating. Both sexes use the scent from night-blooming flowers to help them locate nectar-rich flowers for feeding. In all these cases the moth is responding to these specific odor cues while it is flying. 
The part of the moth's brain that decodes the odor information in the environment is called the antennal lobe. The antennal lobe of Manduca (and most other insects) is built in a very similar way to the part of the human brain that decodes odors for us; the olfactory bulb. Because the odor processing centers of moths and humans are so similar, it is easy to study the moth brain to increase our understanding of the general principles of how brains decode odor information. The most striking similarity between moth antennal lobes and human olfactory bulbs is that many of the neurons in these brain centers are organized into spherical knots of neuronal processes called glomeruli |