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Canis familiaris evolutionary chameleon

April 28, 2018 | 10 Minute Read

The Environment is a collection of biotic and abiotic elements, natural and artificial, existing in a specific area through their mutual relations and associations. Similarly wild Canis lupus lupus same as domestic Canis lupus familiaris (two separate Canis lupus subspecies), come from a common ancestor living - averaging - 400 000 years ago, and the most probable reason of them both splitting up (circa 15 000 years ago) was an appearance of the ecological niche - a habitat established by humans who changed their way of life from nomadic (hunter-gatherer) into settled (agriculture, then animal husbandry). According to Coppinger’s theory, domestication process itself runs based on natural selection. Most confident and social pre-dogs, got used to living close to human settlements, eating garbage, bringing up safely their offspring (fire detered potential intruders, like wild cats living and hunting alone). In exchange, humans gained a warning about danger and deterring other predators (by mature pre-dogs). Smaller individuals adapted to a diet containing leftovers (low quality, less protein, less calories), then they gave up predation and hunting/living in packs for half-solitary scavenging. Domestic dog appeared the first domesticated animal entirely and certainly the first predator put through that process.

Jōmon hunt with dogs recreation, Niigata Prefectural Museum of History, Japan

At the beginning, “village dogs” were selected spontaneously, by choosing those which seemed to be least dangerous - predisposed to play, approaching confidently, not avoiding human touch and not reacting aggressively, thereby not preferring the fellow pack as social behavior manifestation. Most of all, chosen “village dogs” were supposed to not display typical predatory behaviors based on the predatory sequence. Those which used to expose play behavior even when matured (following an object, barking), became perfect guards. Dogs using the prey drive shortened by two unwanted final links were helpful on a hunt (or just served as an example on how to do it).

SEARCHING -> TRACKING -> STALKING -> CHASING -> GRABBING -> KILLING -> DISSECTING -> EATING

Another final link disappeared as a result of selection by feeding only “village dogs” which didn’t attack livestock, and allowing them to reproduce (afterwards their offspring was similarly selected).

SEARCHING -> TRACKING -> STALKING -> CHASING -> GRABBING -> KILLING

Consequently, by manipulation at the predatory sequence, human species achieved a fully functional companion. Domestic dog, less competitive, less predatory than its Canis lupus ancestor, primarily evolved into 3 types associated with human needs - hunting, herding and guarding. Siberian archaeozoological discovery confirms the earliest evidence for dog breeding taking place on remote Zhokhov Island, where Paleo Arctic dwellers were supposed to hunt polar bears, then pursued reindeer to survive frigid temperatures on vast territory in animal-skin tents. Researchers suggest that discovered remains belong to dogs bred to pull a sled (one of them could be a wolf-dog hybrid). A comparison of their skulls to wolf skulls and Siberian Husky’s ones coming from that region proved Canis familiaris subspecies affinity.[1]

Winter sledging on the coast of the Sea of Okhotsk, illustration by Bulychov Ivan Dmitriyevich (1856, St Petersberg, Russia), Scott Polar Research Institute, University of Cambridge, United Kingdom

Along with advancement of civilization, dog breeds[2] were shaped consistently by selection related to their utility - together with exemplary appearance and behavior - required for particular tasks. In harmony with their own standard, some offspring were picked out from every litter in order to let them survive and pass their genes to next generations. Among them ‘ancient breeds’[3] kept the genome almost unchanged (in comparison to gray wolf’s genome); they’re considered to come directly from a common ancestor.
In association with their utility, dogs were divided into
assisting humans during hunting -> sight-hounds, scent-hounds, gun dogs (pointers, retrievers, flushing dogs);
dedicated/specialized working types -> sled dogs, guardian dogs, livestock guardian dogs, herding dogs.
The rest of them became companion animals. Moreover, solidified by generations “infantile” behavior of mature dogs (motivation to play, eye contact tendency) correlated with human focused behaviors and a chance for mental adaptation to varied habitat conditions. An experiment conducted in France, on 36 dogs (contrastively 18 shepherds and 18 molossoids) confirmed their synchronization of the walking pace with the handler, what can reflect on evolutionary adaptation. Tested dogs where unleashed and their owners didn’t look at, talk to nor recall them, walking in pairs whereas humans in random order changed conditions into - normal-walk, fast-walk and stay still (in 10-seconds intervals).[4] All of them synchronized their pace closely with their handlers, speeding up when they started to walk faster - walking at a normal pace is daily routine, also the owner suddenly stopping is nothing unusual. It was significant that they spent more time gazing at the handler fast-walking than in both other conditions, and that shepherds focused longer than molossoids. Shepherds have been selected (and are trained during their life experiences) to work with their owner, to wait for instructions from the owner, on what to do, where to go, whereas molossoid dogs have been selected (and are trained) to be more autonomous, and are thus checking less with their owners.[5] - Charlotte Duranton says, one of authors.
Currently, Canis familiaris counts around 500 breeds (excluding crossbreeds and mongrels), which differ from one another by look, size, mentality or utility itself (in its present meaning). All of them are completely dependent on humans (if they’re not stray, feral or half-wild); their previous functionality changed (or just disappeared). Domestic dog doesn’t have to work (as before), even if it’s contrary to its primal predispositions or inherited tendencies. It supposes to be not a useful by its utility animal, but a family member, house mate, friend; to behave like a tolerant, obedient and patient pet. Potential dog persons travel, change a dwelling place (companion animal habitat), require endurance for their irregular daily rhythm, many-hours absence, stimulus bombardment. More and more frequently it happens that support of a behaviorist is necessary, or an aware dog owner tries to recompense lacks of activity by long, proactive dog walks, interactive dog toys, dog tricks teaching, clicker training. Impulsivity can be described as the inability to delay reward gratification, and in dogs this may sometimes relate to problems such as aggressive behaviour. Historically, Border Collies and Labrador Retrievers have been selected for working purposes requiring different levels of impulse control – livestock herding and gundog work respectively. - Fernanda Fadel says, lead author of the other study conducted on data collected exclusively from pure breed border collies and golden retrievers.[6] - Of course, it would be inappropriate to make predictions about an individual dog’s behaviour only based on its breed, but our findings are extremely interesting. They highlight the varying temperaments of different breeds and also point to the impact that breeding for work or breeding for show can have on the personalities of our pets. We also saw a large variation among individuals of the same breed.[7]
According to domestic dog subspecies primal utility (and because of its lack), dog sports came to existence.
– nosework / tracking -> widely understood activity related to scentwork in closed space or on open area (searching for markers, objects, persons).
– sled dog racing / bikejoring / canicross / dogtrekking -> activities which rely on pulling a sled/bike/human by a single dog or a group of dogs, or just on orienteering.
– coursing -> dedicated to sight-hounds (greyhounds, saluki, whippets), a dog racing serving realization of natural passion of running by chasing a decoy.
– dummy -> dedicated to scent-hounds and the rest of hunt assisting dogs, as a sport which serves realization of their natural fetch tendency (or official dog instinct test).
– sheepdog trials -> dedicated to herding dogs, as a sport which serves realization of their natural herding tendency (or official dog instinct test).
– ipo -> dedicated to guardian dogs (or other dogs predisposed to K9), as a sport strictly associated with absolute obedience and direct protection (including attack on command).
– obedience / rally-o -> a course proceeded by a dog-human team using learned obiedience commands, with the dog mostly in heel position.
– frisbee -> a playing form using a dog - natural or awoken - fetch motivation to make it catch a flying disc thrown by a human.
– flyball -> running of two teams consisting of 4 human-dog pairs each one, based on complete fetch mechanics (every dog in team starts to machine fetching a ball after its spring-loaded pad is pressed, and returns running past the next one waiting at the start line).
– agility -> an obstacle course run by a dog led by a handler using hand points or verbal tips.
Raymond Coppinger once called Canis familiaris the chameleon of evolution. As a subspecies it relatively easily adapts (socialization, habituation) and learns (obedience, puppy school) during its whole life. Education and training are simplified thanks to developed dog senses (scent, sight, hearing), memory (especially olfactory), intelligence and human contact stance regardless type or breed. Lasting hundred years sympathy to breeds creation with emphasis on desired appearance (sometimes at the expense of health) made domestic dog genome limited to relatively shrunken population of specific range (i.e. breed), being a reason to risky decisions about dangers because of genetic diseases present in pedigree lines - matings, or even inbred[8] option. Anyway, only a fraction of counting nearly 400 mln dog population lives close to humans. Some of that fraction are in hands of passionate breeders who still appreciate utility and their domesticated dog primal destination.


[1] Archaeological dogs from the Early Holocene Zhokhov site in the Eastern Siberian Arctic (2017), Institute for the History of Material Culture (Russian Academy of Sciences), research by Vladimir V. Pitulko, Aleksey K. Kasparov.
[2] Breed means a group of individuals within the species, being characterized by a set of mutual, shared, noteworthy attributes, inherited - and solidified - by generations.
[3] Genetically divergent from the modern breeds - Basenji, Saluki, Afghan hound, Samoyed, Canaan dog, New Guinea singing dog, Chow Chow, Chinese Shar Pei, Akita, Alaskan malamute, Siberian husky, American Eskimo dog and Canis lupus dingo. Genome-wide SNP and haplotype analyses reveal a rich history underlying dog domestication, via U.S. National Institutes of Health’s National Library of Medicine, study by collective work (2004).
[4] Pet dogs synchronize their walking pace with that of their owners in open outdoor areas (2017), via Animal Cognition journal, research by Charlotte Duranton, Thierry Bedossa, Florence Gaunet.
[5] citation after the article by Barbara J. King
[6] Differences in Trait Impulsivity Indicate Diversification of Dog Breeds into Working and Show Lines (2016), via Scientific Reports, study by collective work
[7] citation after the article via University of Lincoln, United Kingdom
[8] Inbreeding relies on mating animals cognate to each other, what helps to strengthen favored traits and allows to detect unfavored recessive genes (if carrier individuals are immediately removed from reproduction). Inbreed side effect is so called inbreeding depression causing lifespan decline and fertility regress.
references:
Raymond Coppinger, Lorna Coppinger „Dogs. A Startling New Understanding of Canine Origin, Behavior, and Evolution” (2002), What is a dog? (2015), How Dogs Work (2016)s