Santa and Those Reindeer

(Page 5: Rudolph the Red-Nosed Reindeer)

Long before 1949, when that perennially popular Christmas hit "Rudolph the Red-Nosed Reindeer" was launched, the myth of the reindeer was already well established. English texts from the Renaissance mention the display of antlers during Christmas dances centuries before any belief in Father Christmas, much less the development of his legend.

Rudolph himself first appeared in an illustrated booklet written by Robert May in 1939 for the Montgomery Ward department stores to hand out to children at Christmas, and was used as the theme for the popular song written by Johnny Marks a decade later. It was first performed by Gene Autry, the "Singing Cowboy."

One commonly held view is that Rudolph's nose was red due to a cold. Others claim that the song has saddled Rudolph with the red-nose slur—the implication being that while Santa consumes the milk and cookies left out for him, Rudolph helps himself to the strong stuff. The unexpected triumph of the drunken, inefficient Rudolph over his sober companions chimes with the relaxation of social conventions that has long taken place during winter festivals.

Recent research conducted in Norway, however, offers a more convincing explanation. Unfortunately for Rudolph, reindeer noses provide a welcoming environment for bugs. They have elaborately folded turbinal bones covered with blood-rich membranes, which warm the air as they breathe in and cool it as they breathe out, thereby reducing the loss of both heat and water. (Even when there are icicles and frost on Santa's beard, his faithful reindeer have dry muzzles.) Odd Halvorsen of the University of Oslo suggested some years ago in the journal Parasitology Today that the "celebrated discoloration" of Rudolph's nose is probably due to a parasitic infection of his respiratory system. Even today, he is awed by the response that followed this revelation. "This paper brought me more fame than anything else I have published," he admits.

Despite living in such chilly conditions, reindeer not only share many of the same parasites that plague other ruminants, such as the warble fly, but also are preyed upon by around twenty different parasites that are specific to them. The pentastomid Linguatula arctica, one of a group of creatures called tongue worms, can be found in reindeer sinuses; larvae of the fly Cephenemyia trompe wriggle in the nasal cavity; and nematodes of the genus Dictoyvaulus squirm in the lungs, as do vast numbers of Elaphostrongylus rangiferi larvae. "We have not been able to quantify the combined effects of these parasites, but it is no wonder that poor Rudolph, burdened as he is by parasites, gets a red nose when he is forced to pull along an extra burden like Santa Claus," Halvorsen notes.

Rudolph notwithstanding, it remains something of a puzzle why reindeer are so embedded in modern Christmas culture. They were only one among many kinds of grazing and browsing mammals that once roamed the forests and plains of Europe, northern Asia, and North America. Indeed, ancient reindeer remains suggest that they ranged as far south as Spain and Italy.

They had been established for around a million years by the time humans came on the scene. People hunted reindeer, along with bison, mammoths, wild horses, and many smaller mammals. Reindeer meat is delicious, the fur is light and warm, and the antlers and bones are handy for making tools and ornaments. No wonder the beasts are featured in cave art and rock carvings, such as one found in Sagelva, Norway, that dates back to 2000 B.C.

But reindeer are badly misrepresented during Christmas festivities, according to Caroline Pond of the Open University in England. Pond is a biologist who has studied reindeer with other biologists from the University of Tromso, Norway. Take the depictions of the beasts typically found on cards, for example. True, reindeer are the only deer species for which both sexes have antlers—bone, often branched, that is covered with a thin layer of skin, or "velvet," rich in blood vessels. But the males actually lose their crowning glory around the time that the holiday is celebrated. The reason has to do with sex.

Antlers of mature male reindeer are usually larger than those of females, with the most impressive found in caribou and Norwegian reindeer. They probably evolved as a secondary characteristic of males under sexual selection: they depend on the sex hormone testosterone; are larger, more elaborate and heavier in older males; and are at their biggest during the breeding season, when they are essential for ritual combat and fighting. Afterward, the males are "rutted out" (even Rudolph), exhausted by the loss of body weight and fat reserves. It comes as no surprise that studies have found that male reindeer suffer greater mortality than females.

Changes in the concentration of sex hormones promote bone reabsorption at the base of the antlers in adult males. Eventually the antlers fall off, and there is a delay of up to four months before new ones grow in the spring. Perhaps the inaccurate depictions of Rudolph sporting his antlers wish to deny this seamy side of reindeer life.

The reindeer Lapps, or Sami, an ethnic group living in northern parts of Sweden, Norway, Finland, and Russia, acknowledge this link between virility and antlers by selling powdered reindeer "horn" to the Japanese with the claim that it increases potency. The Sami are unusually virile, but the reason, according to a study by Ilpo Huhtaniemi of Finland's Turku University, is not due to this horny folk medicine but to a genetic mutation.

The mutation is found in 40 percent of Sami men (compared with 25 percent of other men in Finland and 20 percent of Swedes) and apparently maintains a high level of testosterone in older men. It seems that the farther south you go, the lower the incidence of the mutation. "The frequency of the mutation is 15 percent in men from southern Europe, 10 percent in Asian men, and 5 percent in American Indian men," Huhtaniemi says.

The very fact that Christmas card artists show Rudolph with his antlers in place may underscore another unfortunate fact, one drawn to my attention by Odd Halvorsen: the Sami mostly use castrated male reindeer to pull or carry loads. Without their equipment, males have an abnormal antler cycle, so they keep their headgear longer than functional males. To keep his antlers for the sake of the Christmas card, Rudolph would have had to be castrated. "This introduces another sad aspect to the story," Halvorsen says.

The more we know about reindeer, the worse the problems faced by card illustrators become. While the males are squandering their energy on sex and violence, the females are piling on fat, Caroline Pond notes. By the time Christmas arrives, the only adult reindeer with antlers and enough energy to drag around a sleigh full of presents are females. That is why Marks's song should have been about Rosie the Red-Nosed Reindeer.

Reindeer are well adapted to living in a snowy landscape, though one that is more barren than the kind found on Christmas cards. In winter they dig through snow to feed on the plants underneath. Fine, powdery snow is easy enough for them to handle, but if the snow is too deep or too hard, feeding becomes difficult. Snow that melts and refreezes to form a crust of ice can be so firm that the reindeer cannot dig through it to reach the food underneath.

Other reindeer behavior is also misleadingly depicted on Christmas cards. The animals' fur is an efficient insulator; outer hairs are long and hollow, supporting a fine, dense undercoat. Together they trap a layer of warm air. Insulation is so effective that snow does not melt on the backs or heads of reindeer. Rudolph, Dasher, Prancer, and the rest of the crew are so well adapted to the cold that they would probably find loafing around chimneys and firesides with Santa too warm to be comfortable.

For more answers to burning Christmas questions—e.g. What are the likely celestial candidates for the Star of Bethlehem? Is the concept of a virgin birth scientifically feasible? How does snow form? How does Santa manage to deliver all those presents in one night?—check out the full book, The Physics of Christmas.

Copyright © 1998 by Roger Highfield. All rights reserved. Posted with permission of http://www.twbookmark.com. Click here for ordering information for "The Physics of Christmas" at Amazon.com.