Artificial Selection And Domestication

Question 1

Domestification definition

Answer 1

Breeding under human control
Provides a product or service useful to man
Tame
Has been selected away from the wild type

Question 2

What is a domesticated animal

Answer 2

The result of the domestication process

Question 3

Breed definition

Answer 3

A group of animals that has been selected by man to possess a uniform appearance that is heritable and distinguishes it from other groups of animals within the same species

Question 4

Taming definition

Answer 4

The behavioural manipulation of a wild animal to allow it to be confident around humans

Question 5

Pet definition

Answer 5

A domesticated species kept by humans for aesthetic reasons or for pleasure

Question 6

Feral definition

Answer 6

A domesticated species that has reverted to living in a semi-natural state

Question 7

How is domestication studied

Answer 7

Archaeology- bones
Archeological and historical records of human civilisation
Genetic evidence
Phylogenetic analysis

Question 8

Why did domestication take place

Answer 8

Climate change forced a more sedentary lifestyle
Settlement size of populations meant hunter-gathering was no longer a viable source of food

Question 9

Animal partners

Answer 9

species that have been completely moulded by humans and have changed their physical and behavioral characteristics in response to artificial selection by humans
Have undergone complete domestication from a Progenitor species
Have undergone selective breeding to develop distinct breeds

Question 10

What characterises animal partners

Answer 10

Being represented by numerous breeds, each selectively bred for certain characteristics that are enhanced to increase their value to human society

Question 11

Exploited captive mammals

Answer 11

Have been enfolded into human society
Have not experienced a lot of selective breeding- so are very similar morphologically to their ancestral species

Question 12

Key centres for domestication

Answer 12

Central and South America
South-western Asia
Far east Asia

Question 13

Small mammals

Answer 13

Include fur-bearing species or those providing a product or service

Question 14

Classification of domesticated mammals

Answer 14

Animal partners
Exploited captive mammals
Small mammals
Experimental domestications and game farming of mammals

Question 15

Husbanded birds

Answer 15

Equivalent to animal partners- selected and modified into breeds
Eg pigeons or song birds

Question 16

Ranched and game birds

Answer 16

Equivalent to exploited captives

Question 17

Galliforms

Answer 17

Fowl
Turkey
Guinea fowl
Partridges
Pheasant
Quail

Question 18

Anseriformes

Answer 18

Goose
Chinese goose
Muscovy duck
Mallard

Question 19

Ratites

Answer 19

Ostrich
Emu
Rhea

Question 20

Ratites

Answer 20

Ostrich
Emu
Rhea

Question 21

Progenitor species

Answer 21

The ancestor of the animal partner

Question 22

Biological process of domestication

Answer 22

Founder group becomes habituated to humans
Changed with successive generations by natural selection- those able to survive in the man-made environment survive and breed
Changed by artificial selection of traits valued by humans for economic, cultural or aesthetic reasons

Question 23

Conditions that predispose animals to domestication

Answer 23

1 – animals should be “hardy”: must be able to survive removal from its mother before weaning and to adapt to a new diet and environment.
2 - behavioural structure of the species should be allied to that of humans: normal behaviour pattern based on a dominance hierarchy (can accept a human leader)
3 – species should be “comfort-loving”: not adapted to instant flight when threatened.
4 – fast rate of growth.
5 – animals should be “useful”: provide food in an easily accessible form.
6 – breed freely in captivity.
7 – easy to control: placid, versatile in feeding habits and gregarious so that a herd or flock sticks together

Question 24

Home range definition

Answer 24

A restricted area within which individual groups of animals live
Usually the area around a home site over t which the animals search for food

Question 25

Home range definition

Answer 25

A restricted area within which individual groups of animals live
Usually the area around a home site over t which the animals search for food

Question 26

Territory

Answer 26

An area defended from others of the same species
Usually by males

Question 27

Domestication of sheep/goats vs gazelle/deer

Answer 27

Sheep and goats have a social system based around a single dominant leader and have a home range
Gazelle and deer are territorial animals that live in herds without any social structure based on dominance hierarchies

So sheep and goats more easily kept in captive conditions as social leader replaced with a human

Question 28

General effects of domestication

Answer 28

Reduction in body size
Changes in body proportions and appearance
Internal characters and dentition
Neoteny
Behavioural changes
Castration

Question 29

Body characteristics in domesticated animals

Answer 29

Dwarf and giant varieties
Piebald coat colour
Wavy or curly hair
Rolled tails
Floppy ears
Shortened tails- fewer vertebrae
Changes in reproductive cycles (all species except sheep)

Question 30

Why does domestication cause a reduction in body size

Answer 30

Poor nutrition limiting growth
Selection for smaller, more manageable animals

Question 31

Changes in appearance and body proportions due to domestication

Answer 31

Variation in colouration
Thickness of wool coats
Self-shedding wool has been bred out of modern sheep

Question 32

Changes in internal characters as a result of domestication

Answer 32

switch from storage of fat around the visceral organs to subcutaneous locations and as bands within muscles.
—-Fat may be less desirable now from a nutritional perspective but in early societies it was valued as a key food stuff and so there was selection for increased fat deposition

Decrease in brain size

Question 33

Neoteny

Answer 33

Retention of juvenile characteristics in sexually mature adult animals

Question 34

Why are neotenous changes advantageous in domestication

Answer 34

Ensures dominance over domesticated animals due to juvenile behaviour

Question 35

Why is castration important in domestication

Answer 35

Bones grow in length rather than girth
More fat laid down in body tissues
Placating effect on make animals- useful for potentially aggressive species

Question 36

Importance of livestock breeds

Answer 36

Historical value fuels interest in old breeds
Breed differentiation provides genetic variability within the population of any species as a whole.
Loss of any breed type leads to a reduction in the genetic pool.
Maintenance of ancient breed types is critical to ensure that relatively unselected animals, genetically relatively close to the wild progenitor, are available for modern breeding programmes
Conditions that favour human population growth also favour breed diversification
Breed diversification is more likely in remote or difficult areas of the globe

Question 37

Mutation

Answer 37

A sudden heritable change in the genetic material (duplication, replacement or deletion of a gene)

Question 38

Cline

Answer 38

A gradation of measurable characters that are unidirectional and pass into each other without discrete breaks in sequence
- non-discreet mutation produces a subtle change and due to interbreeding a cline is produced

Question 39

Inbreeding

Answer 39

Mating of individuals more closely related than average pairs in the population

Question 40

Process of breed differentiation - biological

Answer 40

1:- A type of animal is defined that is more useful and desirable than the ordinary type but it is not differentiated in pedigree. This distinction may reflect recognition of a cline or the development of a mutation

2:- Some of the best animals of that type are gathered into one or a few herds, which then cease to introduce much outside blood. This population then undergoes inbreeding so that the animals become distinct from other animals in other captive populations.

Question 41

Process of breed differentiation - biological

Answer 41

1:- A type of animal is defined that is more useful and desirable than the ordinary type but it is not differentiated in pedigree. This distinction may reflect recognition of a cline or the development of a mutation

2:- Some of the best animals of that type are gathered into one or a few herds, which then cease to introduce much outside blood. This population then undergoes inbreeding so that the animals become distinct from other animals in other captive populations.

Question 42

Types of variability

Answer 42

Discrete mutations
Clines

Question 43

Types of variability

Answer 43

Discrete mutations
Clines

Question 44

Process of breed differentiation- sociological

Answer 44

3:- If this process is successful then the breed becomes more popular and more herds are established from the original inbred population. Marketing of the breed is crucial in getting accepted and expanding its numbers.

4:- Once the breed becomes numerous, a herdbook is established to record the numerous pedigrees.

5:- A breed society is formed to safeguard the breed and to advance the interest of the breeders.

Question 45

What did domesticated cattle descend from

Answer 45

Aurochs

Question 46

Where did wild aurochs originally survive

Answer 46

1300- NE Europe

Question 47

3 main types of British cattle

Answer 47

Beef
Dairy
Dual-purpose

Question 48

Why are beef cattle chose

Answer 48

Yield
Hardiness
Rate of maturing
Eg Lincoln red, Aberdeen angus

Question 49

Why are dairy cattle chosen

Answer 49

Buttermilk content
Yield
Eg Ayrshire
, jersey

Question 50

Why are dual purpose cattle chosen

Answer 50

Yield of milk and meat
Location
Eg south Devon, belted Galloway

Question 51

Progenitor species of guinea pigs

Answer 51

Cavia aperea
Cavia tschudii

Question 52

Progenitor species of domestic cat

Answer 52

African wild cat- Felis sylvestris

Question 53

Self-domesticated cats

Answer 53

Cats probably ‘self-domesticated’ because they were attracted to human habitation by rodent pest of food stores. Killing mice and rats would have endeared cats to early humans.