Fish Designs

Pectoral & Pelvic Fins

• Used to turn, brake and balance the fish

Dorsal and Anal fins

• Vertical fins used as stabilizers

Adipose Fin

Caudal fin

• Used in propulsion in high speed fish

Caudal Fin

• Can increase vertically to increase surface area to develop thrust

Increased Surface Area

• Although increases Thrust, it also increases Drag

• The efficiency of the design represented by:• Aspect ratio = fin height2/fin area

Heterocercal tailAR=7 to 10Gives lift (no swim bladder) and thrustBad at maneuvering

AR=5good for propulsion and fast maneuvering

AR=1At slow speeds good for maneuvering

AR=7 to 10Good for fast cruising bad for maneuvering

AR=3good for fast speeds and maneuvering

Lateral Line

• The lateral line is a system of sense organs found in aquatic vertebrates, mainly fish, used to detect movement and vibration in the surrounding water.

Operculum

• a flap of the bony fish covering the gills