A whorl ( or ) is an individual

circle A circle is a shape consisting of all points in a plane that are at a given distance from a given point, the centre. Equivalently, it is the curve traced out by a point that moves in a plane so that its distance from a given point is const ...

oval An oval () is a closed curve in a plane which resembles the outline of an egg. The term is not very specific, but in some areas (projective geometry, technical drawing, etc.) it is given a more precise definition, which may include either one or ...

, volution or equivalent in a whorled pattern, which consists of a

spiral In mathematics, a spiral is a curve which emanates from a point, moving farther away as it revolves around the point. Helices Two major definitions of "spiral" in the American Heritage Dictionary are:concentric objects In geometry, two or more objects are said to be concentric, coaxal, or coaxial when they share the same center or axis. Circles, regular polygons and regular polyhedra, and spheres may be concentric to one another (sharing the same center point ...

(including

s and arcs).

Whorls in nature

File:Photograph and axial plane floral diagram of Friesodielsia desmoides.jpg, Botanical whorls: sepals, petals, leaves, or branches radiating from a single point (photo and axial cross-section shown) File:Anisus septegyrus1pl.jpg, Mollusc whorls: Each complete 360° turn in the spiral growth of a mollusc shell. File:Baby hairy head DSCN2483.jpg, A

hair whorl A hair whorl is a patch of hair growing in a circular direction around a visible center point. Hair whorls occur in most hairy animals, on the body as well as on the head. Hair whorls, also known as crowns, swirls, or trichoglyphs, can be either ...

is a patch of

hair Hair is a protein filament that grows from follicles found in the dermis. Hair is one of the defining characteristics of mammals. The human body, apart from areas of glabrous skin, is covered in follicles which produce thick terminal and f ...

growing in a circular direction around a visible center point. File:Fingerprint Whorl.jpg, In a

fingerprint A fingerprint is an impression left by the friction ridges of a human finger. The recovery of partial fingerprints from a crime scene is an important method of forensic science. Moisture and grease on a finger result in fingerprints on surfac ...

, a whorl is each ridge arranged circularly around a central point on the finger. File:Bovine Bone Sample and 430 times Magnification.jpg, In

histopathologic architecture Histopathology (compound of three Greek words: ''histos'' "tissue", πάθος ''pathos'' "suffering", and -λογία ''-logia'' "study of") refers to the microscopic examination of tissue in order to study the manifestations of disease. Spec ...

, a whorled pattern consists of multiple

concentric objects In geometry, two or more objects are said to be concentric, coaxal, or coaxial when they share the same center or axis. Circles, regular polygons and regular polyhedra, and spheres may be concentric to one another (sharing the same center point ...

, or a spiral-shaped pattern.

Bone A bone is a Stiffness, rigid Organ (biology), organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red blood cell, red and white blood cells, store minerals, provid ...

tissue is shown. For mollusc whorls, the

body whorl The body whorl is part of the morphology of the shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk. In gastropods In gastropods, the b ...

in a mollusc shell the most recently formed whorl of a spiral shell, terminating in the aperture.

Whorls in human-made objects

> File:Spindle Whorl (Sulsultin), 19th century, 05.588.7382.jpg, A

spindle whorl A spindle whorl is a disc or spherical object fitted onto the spindle to increase and maintain the speed of the spin. Historically, whorls have been made of materials like amber, antler, bone, ceramic, coral, glass, stone, metal (iron, lead, lead ...

is a disc or spherical object fitted onto the

spindle Spindle may refer to: Textiles and manufacturing * Spindle (textiles), a straight spike to spin fibers into yarn * Spindle (tool), a rotating axis of a machine tool Biology * Common spindle and other species of shrubs and trees in genus ''Euony ...

to increase and maintain the speed of the spin.

Whorls in nature

Whorls in human-made objects

References

See also