Fish fin
Appendages that generate thrust and lift for fish swimming.
Last updated
Fish fins are appendages that can be median or paired, with most fish having both kinds.[1] Fins are supported by bony structures such as spines and soft rays in more evolutionarily advanced fish.[1] The caudal fin acts as a primary appendage for locomotion in many fishes.[1]
Quick Facts
- Field
- Ichthyology, Evolutionary Biology
- Known for
- Diverse anatomical structures and functions in fish locomotion
- defense
- and reproduction
Facts from the source article.
Key facts and history
Ray-finned fishes form a class called Actinopterygii and their fins contain spines or rays.[2] Within the group of bony fishes, two subdivisions exist: those with ray-like fin supports and those with fleshy, lobed fins.[3] The class Sarcopterygii comprises lobe-finned fishes, which are characterized by paired fins that are fleshy and lobed, attached to the body through a sequence of bones.[4] In sharks, the fin skeleton is elongated and gets its support from soft, unsegmented rays called ceratotrichia.[5]
A heterocercal tail, where the upper section is typically bigger than the lower, is a common feature among sharks, most of which have a total of eight fins.[6][7] Rays have pectoral fins that are highly flexible and are attached to the head.[6] A row of small fins that lack rays and cannot be retracted, called finlets, is present along the posterior edge of the body in scombrid fishes.[8]
What the research sources say
The Exploring Our Fluid Earth account notes that median fins can function like a boat's keel and aid in stabilization.[1] The same source describes that paired fins are most commonly used for maneuvering, like oars on a rowboat.[1] The Wildlife Journal Junior account states that bony fish have a swim bladder that helps keep them buoyant.[9] According to the Humane Society International, approximately 100 million sharks are killed each year for their fins in an act known as shark finning.[10]
Research by Nauen and Lauder indicated that finlets have a hydrodynamic effect on local flow during steady swimming.[8] Researchers using volumetric imaging in 2011 found that continuous tail beats resulted in a linked chain of vortex rings.[11]
References
- "Structure and Function - Fish", Exploring Our Fluid Earth: Teaching Science as Inquiry. facts only, no text reused. manoa.hawaii.edu
- Wikipedia, "Fish fin" (CC BY-SA 4.0), which cites: "Chapter 2 Lesson 2 Fins: Form and Function", Fishing: Get in the Habitat! Leader's Guide, 2010; "Structure and Function - Fish", Exploring Our Fluid Earth: Teaching Science as Inquiry; Lindsey, "Fish Physiology", Academic Press, 1978, p. 1–100 (we also read that source) en.wikipedia.org
- Wikipedia, "Fish fin" (CC BY-SA 4.0), which cites: Nelson, "Fishes of the World", John Wiley and Sons, 1994 (we also read that source) en.wikipedia.org
- Wikipedia, "Fish fin" (CC BY-SA 4.0), which cites: Clack, J. A. (2002) Gaining Ground. Indiana University (original not read by us) en.wikipedia.org
- Wikipedia, "Fish fin" (CC BY-SA 4.0), which cites: Hamlett 1999, p. 528 (original not read by us) en.wikipedia.org
- Wikipedia, "Fish fin" (CC BY-SA 4.0), which cites: Function of the heterocercal tail in sharks: quantitative wake dynamics during steady horizontal swimming and vertical maneuvering - The Journal of Experimental (original not read by us) en.wikipedia.org
- Wikipedia, "Fish fin" (CC BY-SA 4.0), which cites: Michael, "Jaws: The Natural History of Sharks", Columbia University (original not read by us) en.wikipedia.org
- Wikipedia, "Fish fin" (CC BY-SA 4.0), which cites: Nauen, "Locomotion in scombrid fishes: visualization of flow around the caudal peduncle and finlets of the Chub mackerel Scomber japonicus", Journal of Experimental Biology, 2001a, p. 2251–63; Nauen, "Three-dimensional analysis of finlet kinematics in the Chub mackerel (Scomber japonicus)", The Biological Bulletin, 2001b, p. 9–19; Nauen, "Locomotion in scombrid fishes: morphology and kinematics of the finlets of the Chub mackerel Scomber japonicus", Journal of Experimental Biology, 2000, p. 2247–59 (original not read by us) en.wikipedia.org
- "Osteichthyes - Bony Fish", Wildlife Journal Junior, 2023. facts only, no text reused. nhpbs.org
- Wikipedia, "Fish fin" (CC BY-SA 4.0), which cites: Shark Finning. Humane Society International. (we also read that source) en.wikipedia.org
- Wikipedia, "Fish fin" (CC BY-SA 4.0), which cites: Flammang, "Volumetric imaging of fish locomotion", Biology Letters, 2011, p. 695–698 (original not read by us) en.wikipedia.org
Each numbered sentence above was checked against the source it cites before publication. Sentences citing Wikipedia adapt text from the English Wikipedia article Fish fin (contributors), used under CC BY-SA 4.0; this entry is available under the same licence. Other sources were used for facts only; no text or images are copied from them.
More in Animal Physiology & Morphology
Sources
Compiled from Wikipedia and the sources listed below. Text from Wikipedia is available under CC BY-SA 4.0; this entry is adapted from it.
- Wikipedia: Fish fin (CC BY-SA 4.0).
- Word definitions: the Codexery glossary, each quoted from its Wikipedia article.
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