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Domestic Dog
When we refer to "
primitive dogs" in these essays what we mean are those
breeds which are thought to be little altered from the
ancestral wolves in both body form and behavioral
attributes. It is pretty obvious that the first changes
that domestication had on wolves were behavioral,
selecting for animals that accepted the presence of
humans without continually challenging in a pecking
order situation. In addition there would be stronge
selection against predatory behavior towards human
infants and children. Much of current speculation on the
domestication of the dog is concerned with what the
first steps in changing a wolf to a domestic animal may
have been.
Primitive Breeds other than Spitz Breeds
Primitive Dogs of the species Canis familiaris
documented to live as feral populations. The primitive,
non-spitz dogs physically are thirty to forty pound
smooth coated dogs with tails that lack the tight curl
of the spitz. In general they have erect ears, sometimes
with a slight turn over at the tip. The Dingo, Carolina
Dog and New Guinea Singing Dog are a sandy red to
cinnamon color.
The Canaan dog is included in some lists as a primitive
dog, here we discuss him among the herding group, he is
often presented as a redomestication of the mid-east
pariah dog. They have been extensively selected as a
herding (drover's) dog and are also used in police work.
Simple changes in appearance such as tail carriage and
coat color might be retained as soon as the mutations
producing them appeared since humans are attracted to
novelty. Another theory concerning changes of coat color
with domestication is based on possibility that changes
in coat color could be directly associated with changes
in the nervous system associated with tameness. This
seemingly unlikely correlation has a good basis in
developmental biology because color is produced by cell
lineages that are derived from the early differentiation
of the central nervous system and many of the
biochemical pathways that produce pigments are also
involved in the production of neurotransmitters.
Similarly embryonic factors that influence the migration
of pigment bearing cells may also influence the
migration of proto-neurons. Before this statement is
taken as something to be extrapolated to humans a
caution is necessary. The commonest change in markings
seen in domestic mammals is the appearance of spotting
(piebald), this is very rare in humans although it is
often associated with sensory disability.
During the early stages of the process of domestication
humans are more likely to have controlled breeding by
elimination of undesired individuals from the breeding
herd rather than by confining fertile females and only
breeding them to selected males.
One of the still unanswered questions in the
domestication of the dog is wether our modern dogs are
derived from different episodes of domestication or only
one episode. If there were mutiple episodes separated in
time and space then some of the disparities we see in
various perceptions of dog domestication could be due to
workers studying animals that are descended, at least in
part, from different founding populations.
Wolves themselves are fairly recent species, some
paleontogists have put the differentiation of wolves
from their coyote/jackal ancestors to be as late as thhe
Pleistocene (the last million years).
When speaking of un-owned animals the term wild is used
for animals that have never been subjected to human
selection (that is, domesticated) while feral is used
for animals that are currently living independently of
human care but whose ancestors were domesticated. As an
example, the free ranging mustangs of the American west
are feral horses, not wild horses, since they are
descended from domestic animals that escaped from their
owners. Animals that are not actively domesticated by
humans but that have become associated with human
habitats and have even shown some adaptation to this
association are called commensals. A good example is the
Norway (brown) rat. Often the presence of these
commensals is undesired and they are then called vermin.
Throughtout the equatorial and temperate regions of the
world we see medium sized dogs that live in conjunction
to human communities yet are not owned. Many writers
such as Dr Lehr Brisbane have suggested that the dogs
found throughout the middle east called "pariah" dogs
are not actually domestic dogs that have returned to an
ownerless state but are actually dogs that were never
really owned, that is they are not feral but commensals.
This theory would have the village scavenger dog be
strongly selected to supress active predatory behavior
towards domestic animals and humans, large and small, as
an adaptation for being allowed to scavenge the wastes
of a human settlement. Such dogs would be expected to
come into existance with the founding of agricultural
settlements. The ecological niche would not be as well
developed for them with nomadic herding people.
Throughout much of the world, with developement, these
dogs are vanishing (this is an observation was pointed
out to me by John Burchard, a mammalogist who has worked
in the middle east) so we may never be able to properly
study them and their relationships with village culture.
Two factors come in to play here. (1) They are often
victums of public health based campaigns to get rid of
such vermin. (2) Their unique gene pool is being changed
by cross breediing with domestic dogs introduced into
the area. One the domestic dog genes are introduced, a
lot of the pariah dog adjustments are lost and the
hybrids can become dangerous to children and domestic
animals which then triggers another round of strategy 1.
Some attempt is being made by fanciers to maintain these
as unique and now domesticated breeds. The Carolina Dog,
and the Canaan Dog are some examples.
The Dingo and the closely related New Guinae Singing Dog
are even more primitive dogs. At times Dingos are
treated as pets and hunting partners by the aborigines
but at other times they are ignored and obtain their own
living. Unfortunately Dingos now have had some European
domestic dog genes brought into their population since
European settlement of the Australian continent.
Attempts are currently being made to rear New Guinea
Singing Dogs as domestic pets in addition to maintaining
them in zoos. |
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