A shark’s sense of smell ties closely to the shape of its nasal olfactory organ. This finding was reported by the press service of Florida Atlantic University.
Traditional beliefs hold that sharks possess an extraordinarily keen sense of smell, allowing them to detect prey from great distances. Unlike most fish, a shark’s respiratory system operates separately from its olfactory apparatus, with odor detection achieved as water is pumped through the nostrils. The distinctive olfactory systems of sharks intrigue researchers not only because of their remarkable scent detection but also due to their ancient lineage; sharks have inhabited the oceans across numerous geological eras, long before the age of dinosaurs.
American researchers conducted a morphological study of numerous olfactory rosettes found in shark noses, documenting their size and shape. To visualize these structures, they performed MRI scans in which tissues were filled with MRI contrast-enhanced iodine. The results showed that the olfactory organ maintains its shape and the number of olfactory plates throughout the animal’s life, underscoring the importance of this sensory system from the earliest days of life.
Additionally, the study noted more lamellae in the longitudinal rosettes compared with the shorter, broader stamens. A greater number of lamellae equates to improved odor perception, indicating that the internal nose structure directly influences scent detection capabilities for sharks.
Among the species examined, small-headed hammerhead sharks (S. tiburo) displayed narrow, long rosettes, while ordinary sea foxes (Vulpinus) and mako sharks (Isurus oxyrinchus) showed rosettes whose length nearly matches their width, with plates that are smaller and less densely arranged. In contrast, blacktip sharks (Carcharhinus limbatus) and American long-nosed sharks (Galeorhinus terraenovae) exhibited rosettes of moderate size and shape relative to the earlier two groups. This variation suggests differences in olfactory sensitivity among species, linked to the internal nose architecture (Source: Florida Atlantic University press service).