(The following article is part of A Layman’s Guide to Ancient Life)
Skins are the hides of animals that have been cleaned of meat and fat, although the fur is often left on to provide insulation. Untreated skins are susceptible to rot and quickly decay in moist climates. Animal skins are usually dried to make rawhide or tanned to make leather, which is more supple and durable.
Wool is an animal fiber that can be obtained from sheep, goats, rabbits, muskox, and camels, most of which have been selectively bred to for long hair and a wooly coat. True wool is distinguished from hair and fur in that it is crimped and elastic, but wool can generally refer to any fiber from long-haired animals (such as cats, dogs, wolves, horses and yak). Wool can be plucked out by hand, combed out, or clipped off with shears.
Wool must first be washed to remove oil and dirt; it is then carded to disentangle the fibers with dried spiky plants (teasels) or wooden/metal combs. Wool lends itself well to felting and can also be spun into yarn, and wool textiles are more durable and elastic than most plant textiles. Wool is a good insulator and can protect from both heat and cold; it can repel water droplets and wick away body moisture, but absorbs environmental moisture and dries slowly. Light-colored wool takes well to dye and can be cleaned by washing with water and/or soap.
Down with long strands (such as those from Ostrich or Turkey) can be cleaned, separated and spun into yarn. Most yarns made with feather down incorporate other longer fibers as a binder.
Silk is a protein fiber produced by insects to build cocoons and webs. Moths, spiders, bees, wasps, and ants all produce silk, but commercial silk is produced almost exclusively from the cocoons of moth larvae which have been bred and reared in captivity. Such larvae can be cultivated in great numbers and are harvested before hatching, leaving the fiber undamaged. The cocoons are dissolved in boiling water, after which the fibers can be unwound and spun. Silk from moth larvae is slightly reflective and has a soft sheen, and is one of the strongest natural fibers. Spider silk is stronger than that of silkworms and can also be spun into yarn, but is much more difficult to mass-produce – it must be harvested from living spiders, and spiders cannot be bred in captivity as easily as larvae. Sea silk is not an insect silk, but refers to the fibers made by mollusks to attach themselves to the seabed. Fibers which are long enough can be spun into a durable yarn finer than larval silk.
Bast fibers are derived from the skin or inner stem layers of select plants such as flax, hemp, jute, reed, nettle, and kudzu. Stems are soaked or exposed to moisture for up to several weeks to soften their outer stalk (retting), after which they are dried and cured for up to several months. The dried stalks are then beaten or crushed and the fibers separated from the woody stem (scutching). The fibers can be combed to remove the shorter strands (heckling), after which the longer strands can be spun into yarn.
Seed fibers are collected from plants which produce bolls ( fluffy protective capsules around their seed) such as cotton and kapok. Originally intended to help disperse seeds through the air, the bolls can be harvested, cleaned of seeds, and carded or combed straight. Seed fiber is more difficult to spin into yarn than bast fiber and is not as durable, but is softer and more flexible.
Dried grasses, reeds and straw from cereal plants can be flattened, peeled, or split into thin strips, softened by steam or hot water, and woven together. Stalk fiber is stiff and best suited for items such as hats and shoes.
The soft bark of certain trees (such as mulberry or cypress) can be soaked, pounded and felted, producing soft strips which can be woven into a rough cloth.
Asbestos is a silicate mineral that forms naturally-occurring fibrous crystals which can be spun into yarn. Asbestos is fire-resistant, and cloth woven from asbestos yarn does not burn when exposed to flame. When mined and worked small asbestos fibers break off, and inhalation of those fibers can cause respiratory conditions.