2,500 Arabia For the other four domesticated large mammal species— reindeer, yak, gaur, and ban-teng—there is as yet little evidence concerning the date of domestication. Dates and places shown are merely the earliest ones attested to date; domestication may actually have begun earlier and at a different location. of ancient humans. Europeans today are heirs to one of the longest traditions of animal domestication on Earth—that which began in Southwest Asia around 10,000 years ago. Since the fifteenth century, Europeans have spread around the globe and encountered wild mammal species not found in Europe. European settlers, such as those that I encounter in New Guinea with pet kangaroos and possums, have tamed or made pets of many local mammals, just as have indigenous peoples. European herders and farmers emigrating to other continents have also made serious efforts to domesticate some local species. In the 19th and 20th centuries at least six large mammals—the eland, moose, musk ox, zebra, and American bison—have been the subjects especially well-organized projects aimed at domestication, carried out modern scientific animal breeders and geneticists. For example, eland, argest African antelope, have been undergoing selection for meat quality and milk quantity in the Askaniya-Nova Zoological Park in the I 6 8 •GUNS,GERMS, AND STEEL Ukraine, as well as in England, Kenya, Zimbabwe, and South Africa; an experimental farm for elk (red deer, in British terminology) has been operated by the Rowett Research Institute at Aberdeen, Scotland; and an experimental farm for moose has operated in the Pechero-Ilych National Park in Russia. Yet these modern efforts have achieved only very limited successes. While bison meat occasionally appears in some U.S. supermarkets, and while moose have been ridden, milked, and used to pull sleds in Sweden and Russia, none of these efforts has yielded a result of sufficient economic value to attract many ranchers. It is especially striking that recent attempts to domesticate eland within Africa itself, where its disease resistance and climate tolerance would give it a big advantage over intro-1 duced Eurasian wild stock susceptible to African diseases, have not caught;; on. Thus, neither indigenous herders with access to candidate species ove thousands of years, nor modern geneticists, have succeeded in making ful domesticates of large mammals beyond the Ancient Fourteen, were domesticated by at least 4,500 years ago. Yet scientists today couJdB undoubtedly, if they wished, fulfill for many species that part of the defini*! tion of domestication that specifies the control of breeding and food ply. For example, the San Diego and Los Angeles zoos are now subjecting the last surviving California condors to a more draconian control of ing than that imposed upon any domesticated species. All individual cc dors have been genetically identified, and a computer program determir which male shall mate with which female in order to achieve human go (in this case, to maximize genetic diversity and thereby preserve endangered bird). Zoos are conducting similar breeding programs many other threatened species, including gorillas and rhinos. But the ; rigorous selection of California condors shows no prospects of yielding|0 economically useful product. Nor do zoos' efforts with rhinos, althou rhinos offer up to over three tons of meat on the hoof. As we shall see, rhinos (and most other big mammals) present insuperable obstacles I domestication. inall, of the world's 148 big wild terrestrial herbivorous mammals the candidates for domestication—only 14 passed the test. Why did other 134 species fail? To which conditions was Francis Gallon re when he spoke of those other species as 'destined to perpetual wildnessl ZEBRASAND UNHAPPY MARRIAGES • 169 The answer follows from the Anna Karenina principle. To be domesti-ated a candidate wild species must possess many different characteristics. Lack of any single required characteristic dooms efforts at domestication, just as it dooms efforts at building a happy marriage. Playing marriage counselor to the zebra / human couple and other ill-sorted pairs, we can recognize at least six groups of reasons for failed domestication. Diet. Every time that an animal eats a plant or another animal, the conversion of food biomass into the consumer's biomass involves an efficiency of much less than 100 percent: typically around 10 percent. That is it takes around 10,000 pounds of corn to grow a 1,000-pound cow. If instead you want to grow 1,000 pounds of carnivore, you have to feed it 10,000 pounds of herbivore grown on 100,000 pounds of corn. Even among herbivores and omnivores, many species, like koalas, are too finicky in their plant preferences to recommend themselves as farm animals. As a result of this fundamental inefficiency, no mammalian carnivore has ever been domesticated for food. (No, it's not because its meat would be tough or tasteless: we eat carnivorous wild fish all the time, and I can personally attest to the delicious flavor of lion burger.) The nearest thing to an exception is the dog, originally domesticated as a sentinel and hunting companion, but breeds of dogs were developed and raised for food in Aztec Mexico, Polynesia, and ancient China. However, regular dog eating has been a last resort of meat-deprived human societies: the Aztecs had no other domestic mammal, and the Polynesians and ancient Chinese had only pigs and dogs. Human societies blessed with domestic herbivorous mammals have not bothered to eat dogs, except as an uncommon delicacy (as in parts of Southeast Asia today). In addition, dogs are not strict carnivores but omnivores: if you are so naive as to think that your beloved pet dog is really a meat eater, just read the list of ingredients on your bag of dog food. The dogs that the Aztecs and Polynesians reared for food were efficiently fattened on vegetables and garbage. Growth Rate. To be worth keeping, domesticates must also grow quickly. That eliminates gorillas and elephants, even though they are vegetarians with admirably nonfinicky food preferences and represent a lot of meat. What would-be gorilla or elephant rancher would wait 15 years for his herd to reach adult size? Modern Asians who want work elephants find it much cheaper to capture them in the wild and tame them. Problems of Captive Breeding. We humans don't like to have sex under watchful eyes of others; some potentially valuable animal species don't 17o' GUNS, GERMS, AND STEEL like to, either. That's what derailed attempts to domesticate cheetahs, the swiftest of all land animals, despite our strong motivation to do so for thousands of years. As I already mentioned, tame cheetahs were prized by ancient Egyptians and Assyrians and modern Indians as hunting animals infinitely superior to dogs. One Mogul emperor of India kept a stable of a thousand cheetahs. But despite those large investments that many wealthy princes made, all of their cheetahs were tamed ones caught in the wild. The princes' efforts to breed cheetahs in captivity failed, and not until 1960 did even biologists in modern zoos achieve their first successful cheetah birth. In the wild, several cheetah brothers chase a female for several days, and that rough courtship over large distances seems to be required to get the female to ovulate or to become sexually receptive. Cheetahs usually refuse to carry-out that elaborate courtship ritual inside a cage. A similar problem has frustrated schemes to breed the vicufta, an Andean wild camel whose wool is prized as the finest and lightest of any animal's. The ancient Incas obtained vicuna wool by driving wild vicunas into corrals, shearing them, and then releasing them alive. Modern mer– | chants wanting this luxury wool have had to resort either to this same method or simply to killing wild vicunas. Despite strong incentives of|f money and prestige, all attempts to breed vicunas for wool production in captivity
