1. Many of us associate wool with sheep, but other mammals — including alpacas, camels and goats — also produce fibers that can be twisted into yarn and then textiles.
2. It’s possible humans started making wool after noticing that, as the fibrous hairs were scraped from the hide of an animal, they twisted together easily into lengths.
3. Wool fibers — made mostly of alpha-keratin, which is found in all mammalian hair as well as horns and claws — stick together easily. The cells of their outer layer, or cuticle, have evolved to overlap like tiny shingles, creating spots for one fiber to catch on another as they are twisted.
4. Clothing and other items made of wool have been found throughout much of the ancient world, from 3,400-year-old Egyptian yarn to fragmentary textiles unearthed in Siberian graves dating from the first century B.C.
5. The process of making wool fabric from fibers was rough going at first — literally. Wild and early domesticated sheep have a bristly overcoat called the kemp and a fine undercoat of wool called the fleece. Over time, animals were selected for more fleece, with finer fibers, and less kemp. The more than 200 domesticated sheep breeds today are mostly kemp-free.
6. Modern wool fibers range from a fine 16 microns in diameter, from merinos, to 40 microns.
7. That itch from your warm winter woolies? Most likely it’s sensitivity to thicker (and coarser) fiber diameter or fiber ends, not a wool allergy, which is practically unknown.8. Less lush pastures — such as in a drought — can produce finer fibers, with smaller diameters.
9. Wool has been a valuable commodity across cultures and centuries. When Richard I (the Lionhearted) was captured in 1192, Cistercian monks paid their part of the ransom to the Holy Roman emperor in 50,000 sacks of wool (a year’s clip).