Domestication Domestication production of new species of plant

Domestication • Domestication = production of new species of plant and animals by human intervention and co-evolution – interference in the life cycles of plants and animals so subsequent generations are of greater utility for and in more intimate contact with humans – domestication demands increased dependence on humans, and vice versa – Domesticate defined as new species, having undergone some morphological change from wild species, but domestication as process more complicated than this

Domestication and Management • Management and casual tending • Domestication: biological process that involves changes in the genotypes and phenotypes of plants and animals as they become dependent on humans for reproductive success (intentionality and co-evolution) • Cultivation: intentional preparation and management of planting areas • Herding: intentional changes in relations between humans and gregarious animals • Agriculture: commitment to this relationship between humans and plants and animals. Production of food and goods through farming and forestry. Agriculture was the key development that led to the rise of human civilization, with the husbandry of domesticated animals and plants (i. e. crops) creating food surpluses that enabled the development of more densely populated and stratified societies. • Population and Landscape domestication

Canis lupus 12/05 Canis lupus familiaris

Was domestication actually “selfdomestication, ” the colonization of new ecological niches by animals such as wolves? Or did it result from intentional decisions by human beings? A little of both: Co-evolution (a) Goyet Dog (Belgium, ca. 3231 k); (b) captive wolf; (c) wolf Natufian human and dog burial (14 -12 k); Dogs came to Americas, Australia, and Africa with humans

Paleolithic Dog DNA, 15 -100 k Geographic range of Canis lupus Although considerable variation occurs in the fossil canid isotope signatures between sites, the Belgian fossil large canids preyed in general on horse and large bovids. J. Archaeological Science (2/09)

Camp followers, new niche Dingos in Australia with humans

9 -7, 000 BP 3 -2, 000 BP 2, 100 BP

Dimitry Belyaev (late 1950 s) behavioral experiment: From a farm breed population of Silver Foxes (20 -30 generations to domesticate; 10 to usable levels) “To evaluate the foxes for tameness, we give them a series of tests. When a pup is one month old, an experimenter offers it food from his hand while trying to stroke and handle the pup. . The pups are tested twice, once in a cage and once while moving freely with other pups in an enclosure, where they can choose to make contact either with the human experimenter or with another pup. The test is repeated monthly until the pups are six or seven months old. At seven or eight months, when the foxes reach sexual maturity, they are scored for tameness and assigned to one of three classes. The least domesticated foxes, those that flee from experimenters or bite when stroked or handled, are assigned to Class III. (Even Class III foxes are tamer than the calmest farm-bred foxes. Among other things, they allow themselves to be hand fed. ) Foxes in Class II let themselves be petted and handled but show no emotionally friendly response to experimenters. Foxes in Class I are friendly toward experimenters, wagging their tails and whining. In the sixth generation bred for tameness we had to add an even higher-scoring category. Members of Class IE, the “domesticated elite, ” are eager to establish human contact, whimpering to attract attention and sniffing and licking experimenters like dogs. They start displaying this kind of behavior before they are one month old. By the tenth generation, 18 percent of fox pups were elite; by the 20 th, the figure had reached 35 percent. Today elite foxes make up 70 to 80 percent of our experimentally selected population. Now, 40 years and 45, 000 foxes after Belyaev began, our experiment has achieved an array of concrete results. The most obvious of them is a unique population of 100 foxes (at latest count), each of them the product of between 30 and 35 generations of selection. They are unusual animals, docile, eager to please and unmistakably domesticated. ” from L. Trut, American Scientist (1999)

Darwin noted in chapter 1 of On the Origin of Species, “not a single domestic animal can be named which has not in some country drooping ears”—a feature not found in any wild animal except the elephant. • In a wide range of mammals— herbivores and predators, large and small — domestication seems to have brought with it strikingly similar changes in appearance and behavior: changes in size, changes in coat color, animals’ reproductive cycles, docility. • Of 148 large terrestrial herbivorous mammals, only 14 have been successfully domesticated

Among wild mammal species that were never domesticated, the six main obstacles proved to be a diet not easily supplied by humans (hence no domestic anteaters), slow growth rate and long birth spacing (for example, elephants and gorillas), nasty disposition (grizzly bears and rhinoceroses), reluctance to breed in captivity (pandas and cheetahs), lack of follow-the-leader dominance hierarchies (bighorn sheep and antelope), and tendency to panic in enclosures or when faced with predators (gazelles and deer, except reindeer). J. Diamond, Nature (2002)

Years before present

Sus scrofa domesticus

Eurasian wild pig (Sus scrofa)

Geographic positions of European and Near Eastern pig haplotypes over the past 13, 000 years Larson G et al. PNAS 2007; 104: 15276 -15281

Landscape domestication and management of non-domesticated plants and animals and incipient or semi-domesticates

J. Diamond, Nature (2002)

Top agricultural products, by individual crops (million metric tons) 2004 data Sugar Cane (grass) 1, 324 Maize (grass) 721 Wheat (grass) 627 Rice (grass) 605 Potatoes (tuber) 328 Sugar Beet (tuber) 249 Soybean (legume) 204 Manioc/Cassava (2002) (tuber) 184 Oil Palm Fruit (tree) 162 Barley (grass) 154 Tomato (fruit) 120 Source: Food and Agriculture Organization (FAO)