Dog domestication & biology

Question 1

dogs descent from wolves

Answer 1

• Middle eastern grey wolf (canis lupus)
• Domesticated for hunting skills ~33,000 yrs ago
• Selected friendliness & neotenous characteristics (retaining juvenile characteristics)
• Bred dogs to fit our lifestyles: hunting & gathering, herding, livestock guarding, urbanization

Question 2

Genetics & mutations

Answer 2

• Some genetics not selected for directly, instead occur due to relaxation of natural selection
• Some harmful mutations accumulate faster in populations where natural selection is relaxed = reduced fitness
  
  • Ex: when dogs start to live w/ humans, less fit individuals were more likely to survive and reproduce than they would in the wild
  • Increased disease & medical problems arising from exaggerated phenotypes (ex: pugs)

Question 3

paedomorphism

Answer 3

• retention of juvenile features
• Physical features: smaller size, shorter muzzle, domed head, larger eyes, smaller teeth, floppy ears etc.
• Behavior: increased care-soliciting behaviors such as begging, face-licking, reduced fear, curiosity, playfulness, reduced territoriality, increased social contact
• Other behavioral changes: earlier sexual maturity, relaxed estrous cycling, better social-cognitive skills
  
  • come intro estrous cycle at different times of the year => wolves depend on season

Question 4

dog social behavior

Answer 4

• highly social, function as family unit
• more similar to juvenile wolves
• show evolved social cognition compared to wolves
• can be trained using human attention (positive reinforcement) as a reinforcer, wolves cannot
• Need & enjoy play and social activities
• Benefit & enjoy being around other dogs and even other species
• Strong social bonds w/ humans => similar to parent-child relationships
  
  • dog & owner release oxytocin

Question 5

basic facts

Answer 5

• Diurnal activity patterns, match owner
  
  • 12-14 hrs sleep per 24 hr, breed & age differs
• spay/neuter 6-9 months of age (sexual maturity; depending on breed)
  
  • Negative health effects if done earlier for larger dogs

Question 6

puppy socialization

Answer 6

• sensitive period is 3-16 weeks
• Habituate to novel stimuli: people, places, noises, objects, etc.
• Slow intro, stop if signs of fear/stress
• Help develop them into a great pet: friendly, confident, show normal behavior, helps improve health
• Puppy socialization classes important!

Question 7

vision

Answer 7

• Function under low light
• Poor visual acuity in bright light (can’t see details far away, only 6ft away)
• Sensitive to motion: likely due to hunting, good at detecting fast moving things
• See only green-yellow & blueish hues
• Can’t see an image if its too close to eyes (<33-50 cm)
• Can’t detect detail if objects too far away

Question 8

olfaction

Answer 8

• Important method of communication (like can smell low glucose levels)
• Scent detection (can identify, categorize & match smells using memory)
  
  • 80% of dog-dog encounters involve sniffing
• Vomeronasal organ enables detection of species-specific chemical signals (like pheromones)

Question 9

hearing

Answer 9

• Adapted for hunting
• Mobile pinna to capture sound
• Hear ultrasound; 67-45,000 Hz

Question 10

vocalizations

Answer 10

• Barking - domestication
• High variability, context specific
  
  • Ex: low freq, short bark = strangers
  • Ex: high freq bark, slow pulsing = play, isolation
• selected for vocalization

Question 11

feeding behavior

Answer 11

• Carnivores but will consume other foods
• Large, infrequent meals b/c there are periods of feast-famine in wolves