Animal Domestication

The first _ was identified from _ (uncalibrated), this specimen is much older than most scientists expected to find for domesticated dogs

Paleolithic dog; Goyet Cave in Belgium (a). At 32,000 years old

animal domestication

the process by which a population of animals becomes adapted to humans and to the captive environment by some combination of genetic changes occurring over generations and environmentally induced development events recurring during each generation

how do animals become domesticated

through a combination of genetic changes occuring over generations and environmentally induced developmental events recurring during each generation

domestication

a process whereby populations of animals change genetically and phenotypically (behavioral and physiological)

what is domestication drive by

selective pressure based on human desired traits

domestication is an _ process drive by _

evolutionary process; selective pressures

what are the four types of selection pressures? define them

1. natural: survival of the fittest

2. artificial: the process of breeding organisms with specific traits; conscious and human induced

3. unintentional: a type of human induced selection pressure where human activity inadvertently influence the evolution of a population by selecting traits without conscious effort

4. relaxed: a reduction in the strength of natural selection on a trait

what were some reasons for early domestication? (3)

1. economic and religious purposes

2. biological causes - the daily behavior of humans led to close associations with animals what were attracted to fields

3. crops attracted animals into corrals

how does the process of hunting relate to domestication

Advancement of hunting technique from stalking and ambushing to driving animals into corrals leading to capture of more than could be eaten before meat would spoil, thus meat could be stored live – basically cows in a fence are just meat sources but still living

animals that _ to human captivity _

preadapted to human captivity successfully reprocuded

what are pre adaptations to domestication (6)

1. docility

2. generalist feeder: can eat many things and adopt to foods in different environments

3. social

4. promiscuous or polygamous mating systems

5. non-territorial

6. ecologically flexible

what are the two different types of young animals?

altricial: helpless - example songbirds, rodents, cats, dogs, etc.

precocial: able to function soon after birth — chickens, ducks, cows, pigs, etc.

what factors shape the behavior of wild animals? (40

1. forces of evolution

2. natural selection

3. mutation

4. gene flow between populations

what factors shape the behavior of domestic animals? (4)

1. forces of evolution

2. natural selection

3. artificial selection

4. relaxed selection

all changes that increase _ are favored in evolutionary processes

fitness

how do we evaluate fitness (2)

1. did the animal survive — could they locate food, shelter, and avoid predators

2. how many offspring did they have? — could they locate mates, reproduce, and care for young?

animals with high _ pass on more _ to the next generation

fitness; genetic material

what are the 5 stages of domestication

1. loose ties between humans and animals; interbreeding with wild forms is common and animals closely resemble wild forms

2. humans control the breeding and prevent interbreeding with wild forms; begin to select for small size, small “weapons” and docility to reduce fear from humans and tolerance of confinement

3. limited breeding with wild forms to increase size for greater meat production but limited behavioral regression

4. selection of desired traits intensifies and breeds develop

5. wild ancestors are hunted to near extinction to protect the artificially selected genetic shock

what is the sixth stage of domestication

the relaxation of natural selection is more pronounced with modern intensive agricultural practices; animals with inadequate or maladaptive responses survive and reproduce anyway

what changes are seen in domestication (5)

1. losses in fitness (often caused by health care, artificial insemination, etc.)

2. cognitive mechanisms — reduced responsiveness to changes in environment

3. neoteny: delaying or slowing of the physiological or somatic development of an organism; organism retains juvenile characteristics into adulthood

4. size and coat differences

5. little change in behaviours but difference in frequency of behaviors

what genetic mechanisms influence the domestication process? (3)

1. inbreeding — increase homogeneity

2. genetic drift — genes may be fixed by chance in a small population; a random process that changes the frequency of alleles in a population

3. artificial selection — conscious or unconscious selection; goal oriented

how do breeds relate to domestication?

we continue to use artificial selection until characteristics are fixed leading to vastly different looks in the same species

domesticated is not the same as _

tame

domesticated

permanent genetic modification that can lead to a predisposition to associating with animals; applies to a whole species

tame

conditional behavioral modification at the individuals animal level

a domesticated animal can be _ and a wild animal can be _

untame; tame

feralization

animals no longer subjected to artificial selection and natural selection pressures become more intense

feralization is _

domestication in reverse

animals that have undergone feralization are now considered _ while domestic animals still experiencing genetic change associated with feralization can be referred to as _

wild animals; feral animals

what are the reasons to domesticate animals (14)

1. income

2. financial assets

3. social value (dowries)

4. food

5. fiber production

6. draft work

7. hunting and/or sporting

8. control of other species

9. protection

10. religious ceremonies

11. war

12. guide and working animals

13. human companions

14. scientific research

sketch a brief timeline of the eras of domestication

what were the successful animals of domestication (7)

1. goats

2. sheep

3. cattle

4. horses

5. pigs

6. chickens

7. dogs

what were the failed animals in terms of domestication (2)

1. moose

2. gazelle

what types of behaviors facilitate or impede on domestication (5)

1. group structures

2. sexual behaviors

3. parent young interactions

4. responses to humans

5. other

which group structures are favorable to domestication (3)

1. large social groups such as the flock, herd, or pack

2. hierarchical group structures

3. males affiliated with female groups

what are unfavorable group structures (3)

1. family groupings

2. territorial structures

3. males in sperate groups

what are favorable sexual behaviors (3)

1. promiscuous mating systems

2. males dominant over females

3. sexual signals provided by movements or posture

what are unfavorable sexual behaviors (3)

1. monogamous mating systems

2. male must establish dominance over or appease females

3. sexual signals provided by color markings or morphological structures

what are favorable parent young interactions (3)

1. critical period in development of the species i.e. imprinting

2. female accepts other young soon after parturition or hatching

3. precocial young

what are unfavorable parent young interactions (3)

1. species bond established on basis of species characteristics

2. young accepted on a basis of species characteristics i.e. color pattern

3. altricial young

favorable responses to humans (2)

1. short flight distance away from humans

2. low reactivity to humans or sudden changes in environment

unfavorable responses to humans (2)

1. extreme wariness and long flight distance

2. easily disturbed by humans or sudden changes in environment

what are some other favorable characteristics in animals for domestication (3)

1. omnivores

2. adaptations to a wide range of environmental conditions

3. limited agility

what are some other unfavorable characteristics in animals for domestication (3)

1. specialized dietary habits

2. requirement of specific habitat

3. extremely agile