Certain living objects and fabrics have a unique shape very similar to the old spindles used in spinning. The shape of these bodies is characterized by an elongated appearance where the front and back are narrow and the central part wider. Bodies with this feature are called fusiform bodies .
Among them, we can highlight certain muscles, some projectiles, submarines, airplanes, the bodies of some aquatic animals and birds.
This form has a specific function in each case.
Some aquatic species are fusiform or ellipsoid as a result of a long evolutionary process . Thus, the shark and the dolphin have this characteristic in their morphology because in this way they glide better through the water. This phenomenon is typical of evolutionary convergence, that is, two different species evolve in a similar way in order to better adapt to their natural environment. fusiform bodies
Airplanes and submarines are fusiform bodies because with this type of structure they achieve a more effective displacement. In the case of an airplane, the shape of the ellipsoid is what facilitates the movement of air through the fuselage . Submarines have a cylindrical shape in order to avoid friction with water. Both planes and submarines are fusiform bodies for aerodynamic reasons. fusiform bodies
The muscles of the human body have several structures: flat, circular, fan-shaped, orbicular or fusiform. In the latter case, it is a type of muscle that is thick in its central part and thin in its extremities. The biceps of one arm is fusiform and thanks to it intense and voluntary movements of force are performed.
The flight of birds is related to their morphology
The body of birds is spindle-shaped in its central part. Its morphology is structured in four parts: head, neck, trunk and tail. Its epidermis is formed by feathers and scales on the feet. Birds’ wings are embedded in their ribs because their body’s spindle shape is designed to fly aerodynamically. This same structure of birds is presented by planes, since the wings are inserted in the fuselage. fusiform bodies
Birds make three movements to fly, as they first take off, then flutter and finally soar. In physical terminology, this equates to the thrust, lift, and effect of gravity. For all this to be possible it is necessary that the body structure of the birds is similar to that of a traditional spindle .