ANS 42 - Midterm 1

wild

an animal living in its natural environment undomesticated

companion animal

a pet or other domestic animal

Give 4 examples of evidence for domestication

1) archeological

2) fossil

3) morphological

4) art

Describe the evolutionary history of dogs from a phylogenic perspective

Based on behavioral, morphological, and genetic evidence, the domesticated dog’s closest ancestor is a gray wolf which they genetically diverged from 27,000-40,000 years ago

Do domesticated dogs come from gray wolves?

no, they are sister taxa that come from a common ancestral wolf that’s now extinct and have two branches diverging from the same point on the phylogenetic tree

Understand the timeline of canine domestication in relation to the timeline of domestication of other species

Dogs were the first domesticated species

What chemicals change in humans with companion animal contact?

increase in dopamine and endorphins

decrease in cortisol and cholesterol

domesticated species

one that a human community maintains complete mastery over its breeding, territory organization, and food supply

domestication

a biological and cultural process that leads to the development of unique human-animal relationships

cultural control

wild animals are incorporated into the structure of a human community and they control where the animal goes and who they interact with

biological control

animals become reproductively isolated from the wild animals and change genetically; controlling diet and reproduction

are zoo animals domesticated?

no

Is control the only factor in domestication?

no, tameness and the ability of an animal to adapt to a human environment are also factors

semi-domesticated

species on its way to becoming domesticated

about how many generations does it take to be domesticated?

30

progenitor

wild ancestor

tame

tendency to flee from humans is decreased or gradually diminished

flight initiation distance (FID)

how close you can get to an animal before it flees

is tameness inherited?

no, it is a predisposition that is learned by observing a tame parent

what is the equation for predisposition?

P = G + E

P = G + E meaning

P: phenotype

G: genetics

E: environment

sister taxa

two groups in an evolutionary tree that share the most recent common ancestor

feral

an individual of a domesticated species that’s no longer living in the human community

four criteria to be own species?

1) reproductive isolation

2) genetically distinct from domesticated species

3) on own evolutionary path

4) different from its wild ancestor

what are the first steps of domestication

1) variation within a population

2) decreased FID

Compare and contrast natural selection and artificial selection

natural selection is the survival of a population based on their evolutionary fitness while artificial selection is the selection of specific traits desired by humans

Name three factors that helped facilitate canine domestication

FID, humans transitioning to farming, benefits to wolf (less energy spent hunting)

phylogeny

the history of the evolution of a species or group

what evidence are phylogenies based on

behavioral, morphological, and genetic evidence

speciation event

when an organism diverges into two different species

sister taxa

two species that are each other's closest relatives

how long ago were dogs domesticated

15,000-36,000 years ago

which was the first domesticated animal?

dog

genomic studies

analyzes an organism’s entire set of DNA to understand its evolution

what continent did dogs originate from?

Eurasia

interbreeding

individuals from two different populations are mating and mixing genetics

How many domestication events were there for dogs and where?

3 in Europe, China, and the Middle East

mitochondrial DNA

DNA only inherited from the mother that determines relatedness between organisms and how long they’ve been reproductively isolated from each other

introgression

long-term outcome where genes from one species are successfully incorporated and spread into another's gene pool through repeated interbreeding, leading to evolutionary change

which is short-term and which is long-term:

• introgression

• interbreeding

introgression is long-term, interbreeding is short-term

what are the three theories of canine domestication?

human selection hypothesis, mutual benefit hypothesis, self-domestication hypothesis

which of the three theories of canine domestication was the most likely to happen and why?

self-domestication because as humans turned to farming, the wolves found themselves a more stagnant food source (food scraps), with the more tame wolves getting naturally selected over time because it was more evolutionarily advantages to get closer to humans than it was to stray away from them

what is another word for self-domestication hypothesis

animal initiated hypothesis

explain the three main things that natural selection did to change wolves?

1) new diet of scraps was less nutritionally dense, thus leading to smaller body size

2) pack behavior replaced with semi-solitary scavenging behavior

3) more adapted to reproducing/breeding near humans, causing them to learn more tameness over generations

how did artificial selection change wolves?

humans chose for small size, docile nature, and working traits so that the wolves could be of use to them in their agarian society (village dogs)

what is the scientific name for a domesticated dog

canis lupus familiarus

what is the scientific name for a wolf

canis lupus

what is the scientific name for a cat

felis catus

what is the scientific name for the african wildcat

felis silvestris lybica

3 main phases of dog domestication

1) self-domestication

2) early selection for “village dog” traits

3) intense breeding practices over the last 200 years, mostly for neotenous traits

neoteny

the retention of juvenile traits into adulthood

4 examples of neotenous traits in dogs

1) large eyes

2) round face

3) large head

4) less prominent nose

breed

group of animals within a species having a distinctive appearance

phenotype

similar physical appearance

3 examples of physical changes due to breed development and their issues

1) floppy ears: more prone to ear infections

2) chondrodysplasia: growth plate turns from cartilage to bone too early, causing stunted legs and luxating patellas

3) skin wrinkling/excessive skin folds: dermatitis

explain the difference between dolichocephalic and brachycephalic

dolichocephalic: long, narrow skull which is often associated with speed and accompanied by a long neck and forward center of gravity

brachycephalic: short, compact skull that increases jaw strength and the inability to breath properly

what issues arise with brachycephlics

• stenotic nares- nose cartilage is displaced and makes nostril opening more narrow

• elongated soft palate due to excess tissue that blocks the airway

• tongue too big for mouth

• hypoplastic trachea- smaller tracheal lumen (opening) making it harder to breathe

• heat stroke

• BOAS

what is the meaning of BOAS

brachycephalic obstruction airway syndrome

what are 3 symptoms of BOAS

1) snorting, snoring, or grunting noises

2) reluctance to exercise

3) clear nasal discharge

how is BOAS worsened

heat, being over weight, being over exercised

what is the treatment for BOAS

surgery to shorten soft palate, widen nostrils, and trim the laryngeal saccules (sac that lubes vocal chords)

Describe nine traits that favor domestication

• living in groups

• social hierarchy reduces confrontation (human maintains the “leader” role)

• males dominate females so easier to breed

• less reliance on physical ornamentation to breed

• promiscuous breeding so they can breed with multiple different mates

• tolerance for human environment

• decreased FID

• flexibility in diet

• ability to be confined

Describe seven consequences that resulted from the process of domestication

• improved fertility and fecundity

• earlier puberty so quicker to breed

• improved production (especially in agriculture)

• decrease in deleterious traits

• decrease stress because we provide everything for them

• decrease brain size since they don’t have to thing to survive because we provide everything for them

• they read humans very well

Explain five pieces of evidence that dogs evolved from wolves

• pack social structure

• same number of chromosomes (78)

• similar mitochondrial DNA

• great genetic diversity

• similar behavior

Explain some key differences between dog and wolf development

• critical period (wolf = 2 weeks; dog = 4 weeks)

• behavioral differences (dogs are more obedient, less impulsive, rely on humans)

• communication (wolves lack empathetic skills; dogs have diverse barks and empathy for humans)

Name the five simplified steps of the predatory sequence

1) reactive stage (pup observes the world)

2) play stage (plays with objects)

3) stalking stage (stalks “prey”)

4) heeling stage (assists on hunts and nips heels of prey)

5) kill stage (mature, proficient killer)

Explain how an understanding of canine domestication helps facilitate better interactions with and care of domesticated dogs

Domestication rewired how dogs interact with us meaning they have specific biological, behavioral, and medical needs. Therefore, through understanding their domestication, we can:

• decode their behavior and better their training

• find relevant outlets for their natural drives

• meet their dietary needs

• understand their medical susceptibilities

Compare and contrast canine and feline domestication

compare:

• self-domestication due to commensalism

• provided a use to humans

• changes in coat types and colors

contrast:

• simpler domestication

• fewer changes in structure and size

• semi-domesticated since they still have the ability to hunt and survive independent from humans

• spiritual purposes in Egypt

• tortured and killed due to Christian fears

Give some examples of how cats have been viewed and utilized historically by humans

egypt: physical embodiment of goddess Bastet and highly revered/protected; used as mousers

christians: negative religious views and fears of cats while being tortured and killed

middle ages: used to hunt rats during black death

pre-1800s: used as barn cats; tolerated but not really considered pets

mid-1800s: valued as pets; victorian era started intensive breeding

fertility

the actual number of offspring the animal produces

fecundity

the biological potential to produce offspring

deleterious traits

traits we don’t want or are harmful (ex: predispositions)

oxytocin gaze loop

eye contact between dog and human that results in an increase of oxytocin for both

critical period

when socialization and exploration is most learned/active

Of the five steps of the predatory sequence, which stages are dogs in

1-4, not 5 because of neoteny

what would be an example of a dog breed in stage 1 of the predatory sequence

livestock guardian dogs like great pyrenees

what would be an example of a dog breed in stage 3 and 4 of the predatory sequence

herding dogs like heelers

what would happen to a dog unable to perform part of the predatory sequence that they are

frustration and behavioral issues

define visual communication and provide examples

nonverbal form of communication that includes body postures, facial expressions, and body positions

example: rolling on back to show submission

define olfactory communication and provide examples

communication through odor

example: marking/urinating

define vocal communication and provide examples

communication through vocalizations

example: trapped prey screams to attract another predator so that both predators fight and prey can escape

define tactile communication and provide examples

communication through physical touch

example: allogrooming when animals groom each other

stereotypic displays and example

consistent visual exhibition of a behavior

example: “halloween cat” means ‘I’m scared’ to other cats, but means ‘I’m big and aggressive’ to other species

stereotypy displays and example

a once normal behavior for the species that has turned abnormal due to repetition

example: often seen in zoo animals; big cats pacing

ARB meaning

abnormal repetitive behaviors

Define anthropomorphism and relate that to how we interpret animal behavior

Anthropomorphism is applying human characteristics to a non-human thing. This often leads to us attributing human emotions to animal behavior.

example: we anthropomorphize a dog giving whale eyes after doing something bad as guilt when it is likely just an appeasement/submissive behavior

Give examples of how similar behaviors have species-dependent meaning

a cat slow blinking at a cat means “i’m not a threat,” but a dog may see this and not know what it means

Describe different indicators of emotional state in dogs

positive/relaxed:

• ears forward/relaxed

• relaxed eyes

• alert and interested

• low, wagging tail

• all feet on floor

negative:

• whale eye

• lip curl

• airplane ears

• forehead/eye wrinkles

• paw up

• yawning when not tired

• tail tuck

Give examples of different forms of olfactory communication in different species

skunk: spray to ward off predators

cats: scratch surfaces to spread scent through interdigital scent glands

rabbits: release pheromones that indicate age and reproductive status

conspecific

animals of the same species

ethologist

scientist that studied animal behavior

why are stress signals through body language helpful

it calms the situation by diffusing aggression during greetings, meaning energy doesn’t have to be spent fighting

pheromones

chemical signaling used in communication

Give some examples of tactile communication and their purposes

tactile communication: allogrooming, head butt, kneeding

purposes: social bonding, hygiene/parasite control, spread scent, decrease stress

Describe three different purposes of vocal communication

1) used to alert others of danger or territory

2) used in mate selections

3) aids in escape

Describe 4 functions of the skeletal system for cats and dogs

1) protection of organs

2) support

3) attachment sites for muscles (movement)

4) storage for calcium and phosphorus in bones

Note three characteristics of the feline and canine skeletal systems and how the characteristics benefit the animal

• floating clavicles to aid in shock absorption and extra flexibility (just cats)

• extra vertebrae to aid in flexibility and increase spine mobility (both)

• digitigrade feet bc predators need speed and stability (both)

what is the reflex called that cat’s have that allow them to land on all fours? what are the 4 steps?

righting reflex:

1) turn head toward direction of gravity (down)

2) twist/turn legs and body in same direction (down)

3) arch back to inc drag and slow fall

4) relax body to absorb shock of impact

what two senses does the righting reflex use and how?

vision: see that they’re in wrong orientation

vestibular apparatus (inner ear): fluid inside inner ear responsible for balance

what are the three foot forms, their characteristics, and some animals that have them?

1) plantigrade: flat foot, stable and suitable for walking, all bones touch ground (human, bear, rabbit)

2) digitigrade: walking on balls of foot, only phalanges touch ground and form foot, compromise b/w stability (less) and leg length (more) when stagnant (dog, cats, birds)

3) unguligrade: greatest leg length but not very stable (prey need to run away), walking on tips of toes (end of phalanges), reduction in foot bones (cows, goats, deer)