page_title: Bonnethead
section_title: Pectoral fins and swimming
hierarchical_section_title: Bonnethead / Morphology / Pectoral fins and swimming
caption_attribution_description: Sphyrna tiburo (Atlanta aquarium)
context_page_description: The bonnethead shark or shovelhead is a small member of the hammerhead shark genus Sphyrna, and part of the family Sphyrnidae. It is an abundant species on the American littoral, is the only shark species known to display sexual dimorphism in the morphology of the head, and is the only shark species known to be omnivorous. Sphyrna derives from the Greek word for "hammer", referring to the shape of this shark's head; tiburo derives from the Spanish word "tiburón", meaning "shark".
context_section_description: The pectoral fins on most fish control pitching (up-and-down motion of the body), yawing (the side-to-side motion), and rolling. Most hammerhead sharks do not yaw or roll and achieve pitch using their cephalofoils. The smaller cephalofoil of a bonnethead shark is not as successful, so they have to rely on the combination of cephalofoils and their large pectoral fins for most of their motility. Compared to other hammerheads, bonnethead sharks have larger and more developed pectoral fins and are the only species of hammerhead to actively use pectoral fins for swimming.
caption: Dorsal view showing the pectoral fins
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