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Course Web Site: www.cals.ncsu.edu/course/ans105/ DOGS 20.3 billion spent on pets care 11 billion spent of vet care 9 billion on food Close to 1 billion spent on toys & treats Over 65% talk to their pet as if it were a human Over 50% greet their pet before they great their “human family”
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Course Web Site: www.cals.ncsu.edu/course/ans105/
20.3 billion spent on pets care 11 billion spent of vet care 9 billion on food Close to 1 billion spent on toys & treats Over 65% talk to their pet as if it were a human Over 50% greet their pet before they great their “human family” Etc.
At least 38% of all American households have one (or more) dog. 46,000 veterinarians in the US (28,000 clinics) Dogs are fully integrated in the American society. They are part of the family and evidence has shown that they make people healthier and happier. Why are dogs so integrated into our society? (This is what today’s lecture will discuss)
The origin of the dog: TAXONOMY Kingdom: Animalia (cats and dogs both) Phylum: Cordata (cats and dogs both) Subphylum: Vertebrata Class : Mammalia (cats and dogs both) Order : Carnivora (cats and dogs both) Family: Canidae (this is where cats & dogs have split) Genus: Canis (Genus includes coyotes, jackals, and wolves) Species: Familiaris Therefore, commonly referred to as Canis familiaris!
What is a Carnivore (basically speaking)? Although animals in this order [canids, felids, ursids (bears), procyonidae (raccoons, pandas), mustelids (weasel, ferret), viverrids (meerkat, mongoose) & finally hyenids (hyena)] have a varied diet … their specialty is eating meat (and enjoying catching it!) They have enlarged carnassial teeth (Upper 4th premolar & the bottom 1st molar) ----These teeth are used to shear and tear meat. They also have small, sharp incisors to hold prey & Canine teeth for stabbing and tearing.
What is the history behind the dog? Miacids --- these are the first know canine ancestor, they lived 62 Million years ago and were tree dwellers; they were the first known animals w/ carnassial teeth; and they were plantigrade (therefore they walked on their palms and soles of their feet) --- much slower than the current dog! Viveravines --- branched off from the Miacids around 60mil years ago; became the first cat ancestors
The Canidae (family) of today: This includes 10 genera and 35 species One of these genera is canis. The genus canis includes the following species: grey wolf, red wolf, coyote, jackal and domestic dog. (Therefore these are the dog’s closest relatives) Foxes, African wild dogs, dholes, maned wolves, raccoon & bush dogs all belong to separate genera from the common dog (they are not as related to dogs as many people believe)
The immediate dog ancestor is not 100% certain … however popular thought and scientific evidence strongly points to the canis lupus (grey wolf) and it’s 32 different subspecies. Some of these subspecies are now extinct. The grey wolf subspecies range from the extremely small arabian desert wolf to the extremely large artic tundra wolf. What is the evidence that makes us believe our dog came from the grey wolf? The grey wolf is morphologically (how?), genetically (how?), and behaviorally (how?) similar to the domestic dog.
The domestic dog has 39 pairs of chromosomes just like wolves (grey & red), coyotes, & jackals. Therefore these species can freely interbreed. The social nature of the wolf (primarily grey wolf) is very similar to dogs. They both form social packs from which they live and hunt. In contrast, coyotes commonly live and hunt in pairs and jackals primarily hunt alone. Communication: The body posture (during dominance, aggression, and fear) is very similar between dogs & wolves. Facial expressions are similar Vocalizations are very similar (especially wolf pups to adult dogs)
How did the wolf become domesticated and lead to the development of the domestic dog? First of all, what does domestication mean? It is the breeding & containment of a species under human control. This involves animal changes (including genetic structure). Taming is not domestication. Know the difference between the two!
The primary theory is the one of: Neoteny (persistent infantile characteristics). That an animal is permanently immature in characteristics of importance. Physical features that are examples of neoteny include: decreased overall size, altered (decreased) jaw size & strength, decreased size and number of teeth, prominent foreheads, shorter limbs, & diminished (smaller) secondary sexual characteristics (in males) Behavioral examples of neoteny include: dog being highly curious like wolf pups, and the common easily subordinate nature of dogs to humans (much like a wolf pup to its pack members)
So … when did man meet the dog? Or when did all this happen? Although it is believed that man and dog’s lived together in a symbiotic relationship (helped each other) for around 100,000 years; The first fossil evidence of a pet dog comes from Israel around 12,000 years ago. (See the National Geographic article). Scientist do believe that people were starting to collect pets before this … around 15,000 years ago. In addition, some pet dogs remains were actually dated back 11,000 years from Idaho, USA!
The dog’s early role was to help man by hunting together. Sometimes man would eat wolf leftovers and vice versa. (Of course if the man got hungry enough he ate the dog!) Later---Pleistocene humans started “collecting” wild animals as trophies or as gifts. They quickly realized Grey wolves were the easiest to train and that once tamed they were good to have around. Wolves quickly were trained to guard children, homes, and food. As people began to breed different size wolves and different tempered animals --- people realized the value of herding animals and hunting animals. Gradually the wolf traits started changing and a whole new species was made that existed primarily under human control!
Wolf to Dog (Domestication) • Canis lupus is a widely diverse species; the size, environment, behavior & communication widely differs b/w subspecies of this group! • The large amount of genetic plasticity of the canis lupus gave humans a large “playing field” to develop different dog breeds.
Fertility & Sexual Maturity • Wolf females have 1 estrus cycle per year…dog females have 2 • Wolf males are fertile seasonally; dog males are fertile all year • The dog has social maturity later in life than sexual maturity; equal in the wolf • Wolf pups develop physically sooner than dog pups
Why all these changes? • Elimination of natural pressures • Breed to be easily kept as pets (whining, etc.) • Dog puppies have a longer socialization period than wolf pups… Why important? Survival!
Agnostic Behavior • Dominance is usually settled w/o a lot of trouble w/i wolves … harder w/ dogs sometimes! • Wolves do not want to fight … they need their energy simply to survive … dogs don’t! • The good thing is that most dogs are less dominant by nature compared to wolves and problems easier to handle! • Dogs do not have the full array of predatory behavior shown by wolves (not true w/ all breeds!)
Breeds of Dogs Spread of human population and increased numbers lead to a change in the demands for companion animals…People needed further selection and refinement of dog traits to meet their needs.
Selective Breeding • Definition: Discriminative selection based on presence of desired structural or behavioral characteristics • Used to weed out undesirable traits or to breed in desired traits
Selective Breeding Actually began at least 5,000 years ago but the extremes we see today did not occur until the last 200 years.
Subspecies v/s Breeds Subspecies: natural selection; differ morphologically (form/structure) from original; & geographically (example?) Breed: based on artificial selection by humans – common species – usually not isolated geographically (example?)
Dog Shows There are 370 – 400 dog breeds globally and over 1,000 recorded in history. Presently, the Crufts (largest dog show in England) has over 18,000 dog entries
Dog Shows The AKC currently has 7 breed groups that we will discuss: sporting, hounds, working, terrier, toys, herding, & non-sporting (153 breeds). A miscellaneous class also exists … but not with full recognition & not discussed in 105. In this course … we are only going to talk about the AKC breeds since they are the most popular US dog breed organization
