Spine

Spine or Spinal may refer to:

Science

Biology

Medicine

Bookbinding

Bookbinding is the process of physically assembling a book from an ordered stack of paper sheets that are folded together into sections or sometimes left as a stack of individual sheets. The stack is then bound together along one edge by either sewing with thread through the folds or by a layer of flexible adhesive. For protection, the bound stack is either wrapped in a flexible cover or attached to stiff boards. Finally, an attractive cover is adhered to the boards and a label with identifying information is attached to the covers along with additional decoration. Book artists or specialists in book decoration can greatly expand the previous explanation to include book like objects of visual art with high value and artistic merit of exceptional quality in addition to the book's content of text and illustrations.

Bookbinding is a specialized trade that relies on basic operations of measuring, cutting, and gluing. A finished book depends on a minimum of about two dozen operations to complete but sometimes more than double that according to the specific style and materials. All operations have a specific order and each one relies on accurate completion of the previous step with little room for back tracking. An extremely durable binding can be achieved by using the best hand techniques and finest materials when compared to a common publisher's binding that falls apart after normal use.

Spine (zoology)

In a zoological context, a spine is a hard, needle-like anatomical structure. Spines are found in a wide range of animals both vertebrate and invertebrate.

In most spiny mammals, the spines are modified hairs, with a spongy center covered in a thick, hard layer of keratin, and a sharp, sometimes barbed, tip.

Occurrence

Mammals

Spines in mammals include the prickles of hedgehogs and the quills of porcupines as well as the prickly fur of spiny mice and Tenrec. They are also found on Echidna, a monotreme.

The ancient precursor to mammals, Dimetrodon, had extremely long spines on their backbone that were joined together with a web of skin to form a sail-like structure.

Many mammalian species also have penile spines.

The Mesozoic eutriconodont mammal Spinolestes already displayed spines similar to those of modern spiny mice.

Fish

Spines are found in the rays of certain finned bony fishes including scorpion fish. The sting that is found in a stingray is a type of barbed spine.

Invertebrates