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.
