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Domesticated Animals and their Wild Ancestors
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This article is about the ancestors of domesticated species and the history of their domestication, for the theory of domestication see Domestication.

Domestication is the controlled breeding of wild animals, and ancestors are defined as a plant, animal or person that is related to one having lived previously a considerable amount of time ago. A biological species is a group of organisms that interact and can reproduce with each other, producing fertile offspring. Within a species there are different breeds, and they are considered the same species because they can produce viable offspring, selectively bred for particular characteristics. Evolution is how an entity (e.g. an object, patriarchy, element, organisation) changes over time, and biological evolution is how organisms have grown and changed throughout history. The theory of evolution proposed by Charles Darwin theorised that the evolution of species occurs by descent with modification, natural selection. This is the theory that there is variation within the population and changing external environmental factors can eliminate variation with less favourable characteristics. Darwin used finches within his experiments with various phenotypic differences, such as beak length. He observed that when the weather favoured trees with large seeds, then finches with large beaks had a larger population number then those with small beaks, and if the environment favoured the large seed trees for long enough, the finches with small beaks could risk extinction.

The Wolf Ancestor
The domestic dog is recognised by Canis lupus familiaris and there are currently 208 dog breeds recognised within Australia however, the American Kennel Club recognises 193 dog breeds. In a study completed in 1997 by Robert K. Wayne and a team of international researchers at the University of California, Los Angeles, they supported their hypothesis that the domestic dog has a single common ancestor, the wolf (Canis lupus), with DNA analysis. This study used the DNA from 162 wolves, 140 pure breed dogs of 67 breeds, 5 coyotes and 8 Simian jackals, providing considerable evidence that the domestic dog doesn’t share DNA with the coyote or jackals, sharing DNA with one common ancestor, the wolf.

Domestication of the Wolf
Excluding any precursors to the current domestic dog species, archaeological evidence suggests that dog was the first animal species to be domesticated, likely domesticated to aid in hunting and gathering. As the domestication of the wolf took place, the predecessors underwent many phenotypic changes to arrive at the species of domestic dog present today. The muzzle became wider and shorter, subsequently causing crowding of the teeth and eventually the teeth also became smaller, the skull bone thinner and the eyes rounded.

Wild Cat Ancestor
The domesticated cat present today is referred to the Felis catus which has approximately 50 breeds of cat recognised by the Australian Cat Federation, whereas The International Cat Association recognises 71 breeds of cat. The current Felidae family consisted of three genera, Panthera (big cats such as lions, tigers, leopards, snow leopards, clouded leopards, and jaguars), Acinonyx (Cheetah) Felis (all other ‘small’ cats). The Felis catus is theorised to be descent from Felis silvestris, which diverges into the F. s. silvestris originating in Europe, the F. s. ornata in the Middle East and Central Asia, the F.s. lybica in Africa and Near East and the F. s cafra in South Africa. There is also the possibility of a Chinese Wildcat divagation, the F. s. beiti. The domestic cat has sequence variation within its genome, which can be traced back to its early domestication and breed development. Using DNA analysis of 979 Felis catus and its wild cat predecessors F. s. silvestris, F. s. ornate, F.s. lybica, F. s. beiti, F. s. cafra concluded that each of these wild cat groups are subspecies of Felis silvestris.

Domestication of the Wild Cat
Cats were domesticated in China to harness their skills of hunting and killing small rodents, and this hypothesis is supported by the discovery of a shared grave of a feline and human buried underneath an ancient home in China. The skeletons were dated 9,500 years ago and were surrounded by carved seashells indicating the intrinsic value of the cat within society. There is however, no other evidence for the domestication of cats until 5,500 years after this when cats began to appear in Egyptian paintings. However, a recent discovery of a Felis silvestris skeleton found in a cemetary in Hierakonpolis in upper Egypt, suggests that Egyptians began the domestication of wild cats as early as 3,700 BC, when this skeleton has been theorised to have been buried. It is hypothesised that Egyptians began the domestication of cats due to their religious significance within their culture.

Aurochs Ancestor
The species of the domesticated cow is the Bos taurus which has three major subspecies the Asian indicine, Eurasian taurine, and African taurine. By using both modern and prehistoric DNA markers, findings that Taurine cattle (Bos taurus) and zebu (Bos indicus) descended from the extinct aurochs (Bos primigenius). By analysing medium density Illumina Bovine SNP (single nucleotide polymorphisms) array (approx. 54, 000 loci) across 3,196 individuals (these individuals representing 180 taurine and indicine populations), comparative analysis supports the hypothesis that the rise of the domestic cattle from the aurochs happened through two domestication events. African indicine shares a considerable amount of genetic variation with the Asian indicine, suggesting more recent divergence then the Eurasian taurine.

Domestication of Aurochs
Cattle began to be domesticated when the hunter-gatherer lifestyle began to shift to a farming society, because the relative assurance of food regularly allowed for population growth and settlements. In the past approx. 10,000 years, five species of wild cattle have been domesticated for multiple reasons including meat, milk and transportation. It is also hypothesised that cattle were domesticated in Western Asia for heavy labour such as transport and religious purposes such as sacrifices.

Red Junglefowl Ancestor
The common domestic chicken Gallus gallus domesticus is a known descendant of the Red Junglefowl Gallus gallus which still occurs in the wild. Although several species of the Red Junglefowl may have contributed to the rise of the domestic chicken, the Southeast Asian Red Junglefowl was found to be the most genetically similar and therefore considered the primary ancestor. The Red Junglefowl is one of the only wild ancestors of a domesticated species that is still alive and prominent within their natural habitat, clearly distinguishable from their decedent, the domesticated chicken.

Domestication of the Red Junglefowl
The domestication of the chicken began approximately 10,000 years ago, and it is theorised that the primary reason for the initial domestication was for cock fighting. Successful cock fighters were encouraged to stay close to the human settlement, this encouraged hens to also reside close. This was initially beneficial to the chickens, (protection, leftovers etc) until they became a food source. The earliest evidence found for chicken domestication was found in Northern China, at this time (approximately 10,000 ybp). Using mitochondrial DNA sequences as supporting evidence, it is theorised that these early domesticated chickens contributed to the gene pool of modern domesticated chickens. The domestication of chickens in the last 100 years has further diversified the species, now having different bred chickens for meat and egg production.