COSA, IT SEEMS THAN WHENEVER I BRING UP COTTON TO HUNTING PROFESSIONALS (GUIDES/OUTFITTERS) COTTON IS OUT. THE REASON IS SIMPLY, COTTON DOES NOT WICK WELL. IT RETAINS MOISTURE, THUS MAKING YOU A EASY TARGET OF HYPOTHERMIA. IN THE FIELD YOUR BODYCORE TEMPERATURE WILL DROP, IF NOT TREATED (YOU CANNOT WARM UP) MANY A OUTDOORSMAN HAVE PERISHED ON THE MOUNTAIN. THIS IS A LITTLE MORE CRITICAL WITH COTTON T-SHIRTS,PANTS..... LARGER GARMENTS. ITS VERY DIFFICULT TO GET WARM IN A SNOW, OR RAIN STORM ONCE WET. SWEAT IS ALSO A CULPRIT,...... KEEP YOUR POWDER DRY, YD.