Alpacas evolved in the Andes mountains up to 15,750 feet (4,800 meters) high where the temperatures varied drastically. During the day the harsh sun would beat them down and overnight it would be freezing cold. Alpaca wool developed to protect alpacas against the extremes which is why it offers exceptional warmth.
Alpaca fibers have “semi-hollow” cores, trapping heat in between each fiber, as well as in the “hollow” areas.