Dog Domestication
Dogs will become dogs: Domestication
Human hunter-gatherers and wolves experienced several overlaps as both are social
species, they shared habitat and hunted the same prey. There are several theories to
explain possible routes for domestication of the dog:
1. Orphaned wolf-cubs: Studies have shown that some wolf pups taken at an early
age and reared by humans are easily tamed and socialized. Once these early adoptees
started breeding amongst themselves, a new generation of tame "wolf-like" domestic
animals would result which would over generations of time, become more dog-like.
2. Early wolves would, as scavengers, be attracted to the bones and refuse dumps
of human campsites. Dr. Raymond Coppinger of Hampshire College, Massachusetts,
argues that those wolves that were more succesful at interacting with with humans
would pass these traits onto their offspring, eventually creating wolves with a greater
propensity to be domesticated. Coppinger believes that a behavioral characteristic
called "flight distance" was crucial to the transformation from wild wolf to the
ancestors of the modern dog. It represents how close an animal will allow humans
(or anything else it perceives as dangerous) to get before it runs away. Animals ith
shorter flight distances will linger, and feed, when humans are close by; this
behavioral trait would have been passed on to successive generations, and amplified,
creating animals that are increasingly more comfortable around humans. "My
argument is that what domesticated-or tame-means is to be able to eat in the
presence of human beings.
That is the thing that wild wolves can't do."[a] Hypothetically, wolves separated into
two populations - the village-oriented scavengers and the packs of hunters. The next
steps have not been defined, but selective pressure must have been present to
sustain the divergence of these populations.
3. As a beast of burden: North American Indians used dog-sized travois before
adapting the horse for this purpose, and huskies are famous for pulling sleds for Inuit
communities. It is very probable that the dog was the original beast of burden before
the domestication of the horse or ox.
4. Dogs as a source of food and fur: Whilst Westerners have difficulty thinking of
dogs (or wolves) as a source of meat, wolf fur is a highly prized commodity.
Archaeology has placed the earliest known domestication at potentially
12,000 BCE-10,000 BCE and with certainty at 7,000 BCE. Domestication of the wolf
over time has produced a number of physical changes typical of all domesticated
mammals. These include: a reduction in overall size; changes in coat colouration and
markings; a shorter jaw initially with crowding of the teeth and, later, with the
shrinking in size of the teeth; a reduction in brain size and intelligence and thus i
cranial capacity (particularly those areas relating to alertness and sensory processing,
necessary in the wild); and the development of a pronounced “stop”, or vertical drop
in front of the forehead (brachycephaly). Behaviourally, the wagging of tails and
barking are behaviours only found in wolf puppies, retained via neoteny throughout
the dog's life. Certain wolf-like behaviours, such as the regurgitation of partially
digested food for the young, have also disappeared.
As an experiment in the domestication of wolves, the "farm fox" experiment of Russian
scientist Dmitry Belyaev [b] attempted to reenact of how domestication may have
occurred. Researchers working with selectively breeding wild silver foxes over
thirty-five generations and forty years for the sole trait of friendliness to humans,
created more dog-like animals.
The "domestic elite" foxes are much more friendly to humans and actually seek human
attention, but they also show new physical traits that parallel the selection for
tameness, even though the physical traits were not originally selected for. They
include spotted or black-and-white coats, floppy ears, tails that curl over their backs,
and earlier sexual maturity. It was reported "On average, the domestic foxes respond
to sounds two days earlier and open their eyes one day earlier than their
non-domesticated cousins. More striking is that their socialization period has greatly
increased. Instead of developing a fear response at 6 weeks of age, the domesticated
foxes don't show it until 9 weeks of age or later. The whimpering and tail wagging is a
holdover from puppyhood, as are the foreshortened face and muzzle. Even the new
coat colors can be explained by the altered timing of development. One researcher
found that the migration of certain melanocytes (which determine colour) was
delayed, resulting in a black and white 'star' pattern."[1]
Looks like wolves ruled until they became dogs
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Dogs and Human relationships | Dog Domestication | Ancient Dogs | Canis lupus familiaris
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