The Role of Body Shapes in Fishes

Many people do not think twice about the way a fish is shaped, the placement of their eyes, and how it applies to the fish's natural habitat. But in fact, these are key aspects highlighting the special ability of these creatures. Body shape plays a number of roles in the life of fishes. Castro & Huber (2007) note that the shape of the many species of fish varies greatly from dorsoventrally flattened, to streamlined, to shorter bodies, just to name a few (p. 161). The shape is typically connected to the way in which the fish live their life under the sea (Castro & Huber, 2007, p. 161).

The shape of a fish's body helps them to live in an area of the ocean that is not accessible to fishes that have another distinctive body structure. Castro & Huber (2007) explain the advantages of these specific body shapes to each species of fish as a means of self-defense (p. 161). They continue by noting the differences in ocean environment (i.e. dense green plants, bright coral reefs, or open rocky areas) and how the uniquely shaped fish take advantage of these oceanic characteristics by concealing themselves inside things like coral or other plant life to catch unsuspecting prey for nourishment (Castro & Huber, 2007, p. 161). Some fish have such unique shaped bodies that when they align or reside near particular items, such as rocks or seaweed, they become masked (Castro & Huber, 2007, p. 161). These fish are concealed so well in fact, that they are hard to see even by humans in the ocean (Castro & Huber, 2007, p. 161).

The body shape of fish also has to do with the speed and way a fish swims; some fish swim extremely fast and need a shape that allows them to cut through the water at amazing speed (Castro & Huber, 2007, p. 161). Castro & Huber (2007) also note that some fish's body shape changes over time in order to adapt to their environment effectively (p. 161). The body shape in each particular species of fish plays an extremely important role in their survival in the ocean. Likewise the placement of a fishes eyes is also an important key to survival. Flat fish, such as the Halibut has it eyes located in such a way that accommodates the shape of the fish, allowing it to view its prey and predators from its flattened position.

References:

Castro, P. & Huber, M.E. (2007). Marine biology (6th ed.). New York: McGraw-Hill Higher Education.