If it works so well, why are these sheep wearing jackets?
I don’t know why it is so warm but I do know if one is wearing wool and one gets caught in the rain and gets wet, the wool will still keep you warm. Something cotton cannot do, not to mention synthetic materials. This is the main reason wool is preferred by outdoorsy type people over cotton.
Wool fibers create a lining of still air, one of the best insulators found in nature. These little pockets of air create a dry layer of air next to your skin to hold in heat during colder months and cool your body as outdoor temperatures rise.
Evaporation of moisture is our body’s natural way of keeping cool. Wool helps this process along by drawing moisture from the body during sleep, absorbing it into cells, and reducing skin temperature. When you’re cooler, you toss and turn less often, and sleep more soundly in a deeper REM state.
In summer, outdoor heat is kept away from your skin because of wool’s insulating barrier of air pockets. Sleeping with a lightweight wool comforter acts like an air conditioner.
Where does all that moisture go? The average sleeper gives off nearly a pint of water vapor in an eight-hour sleep period. Wool can absorb up to 30% of its own weight without feeling damp or clammy. The cells of wool fibers are porous, so they quickly and efficiently absorb and evaporate moisture — unlike down, which actually holds moisture and can create mildew.
While cotton fabrics can soak up water wool fibers do not.
So while you can drop a wool blanket in a tub of water it will weight a ton, but you can wring the out. While it will feel damp the crinckly nature of the hairs/threads/fibers will be full of air pockets that insulate you.
If you think wool is exciting, try buying a silk shirt. I find them warmer and less scratchy when I ski.
Have you tried asking a sheep?
Big government liberals hate wool.
If it works so well, why are these sheep wearing jackets?
Would you pardon me while I expound on a theory?
When I was young there was no synthetic bedding.
One had two to three wool blanket on the bed over a sheet. One then had one or two comforters made of heavy cotton batting with duvet covers. Weighed pounds!
If it was really cold parent used to put a crotchet woool blanket or two on top of the whole mound.
Kids were pressed as tightly as pancakes.
When I was ten the family switched to synthetic “puffs”. Boy it was hard to sleep without all the pressure.
My ADD kids sleep best with heavy blankets, woollies when I can get them. Many ADD and ADHD kids use weighted blankets to sleep well.
My theory is that northern cold weather kids have had an increase in behavioral issues due to the lack of pressure while they sleep. Aspberger kids even more so.
I lived in a Filson wool vest most of last winter, and it was great. I didn’t need a jacket sometimes.
A lot of what makes wool and mohair warm is that, when wet or moist, it still insulates. This may be due to polar amino acids holding the water molecules within the helix rather than having water continuous from inside to outside of the fabric, permitting conduction and (liquid) convection.
Also, wool and mohair don't burn and melt easily like artificial fibre, additional reasons that the military use it. I think that for mountaineering, wool is old school. Synthetics are more convenient but not better. If it is your survival, use wool.