Lip muscles also tighten against the elements, to keep the mouth closed and to pull the Caucasian's soft pink lip away from the sun. Indoor people take lip balm with them, because they are not tight-lipped from long practice. Our faces are gray-white from the shade, so we must also throw some sunburn lotion into the pack before an extended outing. Inner and outer weather go together not only in affecting one's spirits of the day, but one's lasting social visage, for there is a large environmental component to social organs. Size and shoulder breadth are alterable by exercise, as the Charles Atlas advertisements dramatize.
Nutrition affects body size and hair luxuriance.
But this particular phenomenon is not limited to human beings. Deer raised on high mineral diets grow larger antlers than do deer raised on minerally deficient diets. Lions in excessively hot areas grow shorter manes than lions in cooler regions. Each population has evolved a potential for social organs depending on the interaction with its surroundings. Deer populations which have lived at low density on highly nutritious browse for millennia maintain their greater potential for developing large antlers even when moved to new habitats.