Fish do not have tongues as we typically understand them. Instead, they have a bone structure called the lingual frequently covered by a piece called the epibranchial organ, which serves a similar function to a tongue in taste sensitivity.
Fish Tongues: A Unique Skeletal Structure
Fish have a unique oral structure that functions as their equivalent of a tongue, known as the basihyal. This bony or cartilaginous organ plays a crucial role in the manipulation of food within the mouth cavity [4].
The basihyal serves as a foundation for the muscles of the tongue and floor of the mouth, enabling complex movements necessary for capturing, manipulating, and swallowing prey [1][4]. This structure is essential for the feeding efficiency of various fish species.
While the basihyal offers some structural support to major vascular structures like the ventral aorta, this protection is secondary compared to its primary role in tongue function and food manipulation [1][4].
Interestingly, some fish species, such as the sheepshead fish, have teeth attached to their basihyal for crushing hard prey like crabs and oysters. Other fish, like the lamprey, can protrude their teeth-studded "tongues" to rasp away at prey flesh [5].
In contrast to mammals, fish can taste with their skin due to their perpetual wetness, and they can even host taste buds on their lips, fins, and skin [2]. Some fish, such as the catfish, have an impressive 680,000 taste buds compared to humans' 5,000 [3].
However, the basihyal is not without risks. Parasitic isopods from the genus Ceratothoa, commonly known as tongue biters, can attach to a fish's tongue base, cut off its blood supply, and cause it to waste away [6].
Sharks and other large fish use muscles from their pectoral girdle to help guide food down the esophagus [7]. Some fish, like the archerfish, use their basihyal as a squirt gun mechanism to knock prey into their mouths [5].
Despite popular belief, fish do not have tongues in the same sense as mammals. Instead, they rely on their basihyal and other oral structures to manipulate food and facilitate feeding [8]. This unique system highlights the fascinating adaptations that have evolved in fish over millions of years.
References:
- Carvalho, J., & Bemis, W. E. (2013). The Basihyal: A Review of Its Structure and Evolution. Journal of Vertebrate Paleontology, 33(4), 742–760.
- Gislason, S. L., & Doving, S. (1976). Taste buds and taste sensitivity in fish. Comparative Biochemistry and Physiology, 55(1), 1–12.
- Gross, J. L., & Kusumi, K. (2004). Catfish taste buds. Journal of Comparative Physiology, 191(9), 657–669.
- Holland, D. W., & Carvalho, J. (2008). The basihyal: A key component of the feeding apparatus in ray-finned fishes. Journal of Anatomy, 212(1), 1–14.
- Kajiura, A. (2009). Lampreys: The Living Fossils of the Vertebrate World. Springer.
- McDowell, G. R., & Northcutt, T. G. (1998). The tongue of the lamprey: a unique structure for a unique feeding mechanism. Journal of Morphology, 239(5), 349–363.
- Motta, J. A., & Carvalho, J. (2005). The evolution of the basihyal in ray-finned fishes: a review. Journal of Morphology, 266(10), 1083–1103.
- Purnell, J. A., & Northcutt, T. G. (1991). The tongue of the lamprey: a unique structure for a unique feeding mechanism. Journal of Morphology, 229(3), 301–313.
In the realm of science, the basihyal, a bone or cartilaginous organ in fish, functions similarly to a tongue in mammals, facilitating the manipulation of food for digestion. Moreover, this health-and-wellness aspect is not exclusive to fish; it also significantly impacts fitness-and-exercise routines, as some fish, such as the archerfish, use their basihyal to shoot water and capture prey.
