ANS 282 - Domestic Dogs

What is one muscular change of domestication and why?

The levator anguli oculi medialis whichich is responsible for the upward eyebrow movement to make dogs appear more juvenile

What is the retention of juvenile characteristics called?

Neotenisation

What changes have resulted from neotenisation?

Floppier ears, shorter muzzles and larger eyes

What are the seven sequences of the hunting sequence?

Search, eye stalk, chase, grab bite, kill bite, ingestion and postprandial quiescence

How has the hunting sequence changed for pointers?

They have a exaggerated search and eye stalk but don’t have the chase, grab bite, kill bite, ingestion and postprandial quiescence 

How has the hunting sequence changed for herders?

They have a exaggerated search, eye stalk and chase but don’t have the grab bite, kill bite, ingestion and postprandial quiescence

How has the hunting sequence changed for retrievers?

They have a exaggerated search and grab bite, intact eye stalk and chase and no kill bite, ingestion and postprandial quiescence

How has the hunting sequence changed for terriers?

It hasn’t

What is a breed?

A homogenous group of animal within a species

What are breed standards?

Selection for certain physical characteristics to ensure animals produced conform to specifics for the breed

What have breed standards inadvertently caused?

Biological and behavior problems

How many breeds does the American Kennel Club recognize?

Over 200

What are the 7 types of dogs that the kennel club recognizes?

Non-sporting, sporting, herding, working, hounds, terriers and toys

What are the pros of breeds?

Predictable physical and behavioral traits

What are cons of breeds?

Working behaviors aren’t always compatible with owner lifestyle and there are hereditary problems

What is inbreeding?

The breeding of closely related individuals, particularly over generations

What is a closed studbook?

Dogs from a breed can only be bred within their breed which can lead to inbreeding

What can inbreeding cause?

Physiological and anatomical problems

What are some breed problems of boxers?

Respiratory problems from their short snouts: nostrils and trachea are too small and the soft palate often droops to obstruct the larynx

What are some breed problems of the Pekinese?

Eyes are shallow and may protrude due to their flat faces

What are some breed problems which Dachshund?

Their long backs may lead to ruptured spinal discs which can cause paralysis and/or chronic pain

What are some breed problems which chihuahuas?

There large heads in relation to their bodies means puppies are often born by c-sections and have open fontanels called ‘molera’ which is considered acceptable in the breed standard, may also have congenital hydrocephalus

What are some other problems of purebred dogs?

Heart disease, coronary disease, blood disease, endocrine disorders, eye disease, skin disease, nervous system disease, digestion disorders, joint disorders, and immunological disease

What are feral/free-living dogs?

Dogs that live mostly outside and free-range though some may be owned by a person or community

What are some common appearances of feral dogs?

Semi-upright ears, narrow faces, short coats, curled tails, medium sized

What is the area centralis?

Area with an extra concentration of photoreceptors; location varies between dog breeds

What is a visual streak?

Where the area centralis is less pronounces and instead, photoreceptors of the retina are more dense alonga horizontal band spanning the middle of the eye

Which dogs are more likely to have an area centralis and why?

Short nosed dogs because they were primarily bred for companionship and this helps them focus and connect with us

Which dogs are more likely to have a visual streak?

Long nosed dogs because they are usually bred for watching and hence need to be able to see larger spaces

At what distance is a dog’s visual acuity best at?

20 feet

What colors can dogs see?

The same as use but they are red/green color blind

Do dogs have relatively good vision in low light? How does it compare to a human or a cat?

Yes, better than a humans but worse than a cat

What is a dogs hearing range?

Up to 60 kHz

What external anatomy helps with dogs superior hearing?

18 different muscles that control ear position

True or false: Dogs middle and inner ear anatomy is similar to humans?

True

What dogs may have worse hearing?

Floppy eared dogs

How are dog’s brains designed for superior olfaction?

Their brains have 300 million olfactory receptors and their portion of the brain dedicated to olfaction is 40x larger than ours

Do dogs have a vomeronasal organ?

Yes, for pheromone detection

What is so special about dog’s nostrils?

Different parts of the nostril inhale and exhale allows for continuous sniffing and the aerodynamic reach of the nostril is smaller than the distance between nostrils so they can determine the odor location by nostril

How can dogs breath and smell?

Air gets separated into two paths, one for olfaction and the other to the pharynx

How do some dogs use their ears to smell?

They can waft scent towards their nose with their ears

What can happen to some brachycephalic dogs’ noses?

Stenotic nares

True or false: The degree of changes exhibited by domestic dogs is greater than any other animal impacted by domestication

True

When were dogs domesticated?

30,000 to 100,000 years ago

What is “alpha dog”/”dominance” training?

Training ideology based on observations of captive, unrelated wolves that competed for resources that asserts that humans must always assert alpha status by force and eat, walking through door, etc first

Is “alpha dog” training a good idea?

No, it’s dangerous, especially to the HAB

What is normal wolf pack structure like?

A family based hierarchy where only the breeding pair mate and is reinforced by subtle behaviors (not aggression)

Can you completely extrapolate dog behavior from wolves or even feral dogs?

No, domestic dogs are far removed from wolves and there is no evidence that they see us as other dogs or think of us as their “pack”

What is the social structure of feral dogs

Largely solitary as they do not live in stable family packs and are more successful scavenging alone than with others

How do people impact dog socialization?

We often force social groupings and mess with their ability to communicate

How do dogs mostly communicate?

Through their body language

What is the acronym to read dog body language?

PET-B

What are signs of a relaxed dog based on PET-B?

Relaxed posture with weight evenly distributed over their legs and no muscle tension, neutral and forward ears, relaxed tail anywhere from level with the dogs back to almost straight down and a tongue lolling out the side of the mouth

What are signs of a fearful/stressed dog based on PET-B?

Submissive posture by trying to make themselves look smaller, ears are pulled back with tension in the forehead and around the eyes, tail is hanging straight down between the back legs, the tongue may be tense and may stick straight out of the mouth or even curl upwards, may be panting, yawning, licking their lips and avoiding eye contact or even moving their body away

What are signs of an extremely fearful dog based on PET-B?

They may bend their legs into a crouched or cowering posture, their ears may be pinned back against the head, the tail may be tucked up towards the dog’s belly

What are signs of a aroused/alert dog based on PET-B?

May try to make themselves appear larger, standing tall and upright as if on their toes, their back may slope upwards towards the head and there may be piloerection of the hair, they may also have an upright tail raised above the line of the dogs back

Does a wagging tail always indicate happiness?

No, it could indicate excitement, aggression and fear

True or false: Dogs and puppies follow pointing and our eye gazes to find treats

True, chimpanzees and wolves don’t preform better than chance

Do dogs pay attention to our facial expressions? How do we know?

Yes, dogs will approach people with their eyes open to beg and will steal treats when their eyes are closed and many studies suggest that dogs can distinguish between happy and sad faces

What do we mean when we say dogs are left gaze bias?

Dogs look primarily at the right side of the face only when looking at people because people show emotion better on the right

Can dogs ask for help?

Yes, studies have shown when giving dogs an impossible task, they will often “look back” at a human to try to communicate seeking human assistance

Can dogs understand human speech?

Yes, dogs can understand 100(0) of human words, equivalent to a 3-4 year old child in some cases, and they may understand the emotion behind it as regions in the brain light up when hearing speech which is similar to the region in humans that recognizes who is speaking and how they are feeling

How have dogs adapted to communicate with us?

They have a larger vocal repertoire than wolves