Sensory ecology: olfaction

Comparative anatomical and genomic data suggest that primates vary considerably in their olfactory abilities. Strepsirrhines have well‐developed main and accessory olfactory systems that differ little from the presumed ancestral condition for crown primates. By comparison, haplorhines have lost or reduced a number of key olfactory structures in the nasal cavity and also lack a rhinarium—a hairless collecting surface on the tip of the nose that is functionally linked to the vomeronasal organ. Catarrhines have further lost all functionality of the vomeronasal organ, although most species still express a small number of vomeronasal receptors in the olfactory epithelium of the nasal cavity. These observations reinforce the impression that olfaction plays an enhanced role in the behavioral ecology of lemurs and lories, and that the importance of olfaction in catarrhine behavioral ecology is greatly diminished.