Many humans despise winter, blaming the season for their blues and inactivity. But I suspect that a true "fear of winter" resides within the collective human psyche. Appropriately called the "Naked Ape" by Desmond Morris, man evolved in the Tropics and spread across the globe before his body changed in any significant way. Rather, the power of the human brain intervened, giving us the ability to fashion warm clothing long before any fur-bearing, northern subspecies evolved.
Humans are equipped with efficient cooling mechanisms (primarily through the skin and lungs) but our heat generating capacity is limited (via shivering, muscular activity and the metabolism of food and stored nutrients). Given adequate fluid and nutrition, a naked human is able to maintain his vital core temperature across a fairly broad environmental range (generally between 55 and 130 degrees F). Hypothermia is of no concern in the Tropics and a naked human could survive in the Temperate Zone for much of the year. But without adequate shelter and clothing, he would quickly succumb to winter conditions.
In this modern industrial and technological age, we seldom consider the limitations and environmental threats that our species once faced. But deep inside, we remember.
