Basics:

behavior, morphology, appearance, reproduction, productivity

reduced sensitivity to environmental changes

reduced aggression

increased tolerance toward conspecifics

domestic behavior is inherited through generations

rooted in wild ancestoral behavior

Process whereby an animal is transformed from a life in the wild to a life under human control, involving complex genetic adaptations (behaivior, morphology, reproduction, productivity) and is a process involving transformation through many generations

in case of dog probably took thousands of years

very little genomic change (dog species 78 chromosomes)

archeological data

historical records

molecular data (mitochondrial DNA vs Nuclear DNA)

greatly increased their numbers

wolves: 400,000 worldwide

dogs: 400,000,000

cow

pig

horse

sheep

goat

"if it is domestic"

ancestral species: wild cat

Near East

9500-1550 BP

majority of breeds in last 50-75 years (dont need that many different traits to be a mouser)

Aurochs Europe Asia and North Africa: extinct, gave rise to two species before domestication occured

Bos tarus taurus - humpless, Europe, northern Asia, West Africa and Americas (fertile crescent) ~10,000 BP

Bos taurus indicus- Humped, arid climate (Indus valley) India and migrated to Asia, China and Southeast Asia~9500 BP

~800 breeds

Wild Boar: in multiple places at the same time

Asia and Europe

~10,000 BP

~200 BP Asian pigs breed with European breeds = phenotypic selection

Fertile Crescent

Domestication of more than one Ovis species

O. orientalis

O. ammon

~13,000 BP

multi domestication events (atleast 3) at different places and different times

~10,500 BP southeaster Anatolia

~9,500 BP Zagros mountains

Wild Horse extinct species

4-5,000 BP

multiple domestication events

mediterranean region ~3,000-5,000 BP for food early ~10,000 BP

350 breeds

Julius Cesar used for communication and into 20th century

racing utility and domestic species have high drive to come home

genomes are extremely similar

function in very similar ways

behavior repertoires of domestic species rooted in those of their progenitors

Process in which individuals with a particular trait tend to leave more offspring in the next generation than do individuals with a different trait.

underlying principles

trait variation (alleles), Heredity, Differenctial reproduction

genes increasing reproductive success are promoted

natural selection is measured after reproduction- by individuals contributing to next generation

artificial selection is measured before reproduction

coat color etc.

have relatively simple genetic architecture

(dog coat color across species is governed by variants in 3 genes)

IGF1 allele = size

(six gene varients explains half dog sizes, 83% of size variation in horses is at 4 loci)

causative alleles which are present in the ancestral species

then there are mutations that are not from ancestral lineage

usually complex architecture: differ in genetic complexity

milk, meat, food efficiency, etc.

~8,000 BP in South Asia

Red jungle fowl

a large phenotypic variation withing a species but this selects for phenotypes which would reduce animal fitness in the wild

selection for performance of narrow specialized tasks

hard to say, it was so long ago

it is also hard to test scenarios for domestication

behvior selection

morphological feature selection

selection for productivity

self selection...

just dont know

Goal: reconstruction of animal domestication in an experiment

hypothesis: selection for behavior was the main driving force of dog domestication

began 1959

close relative of the dog

bred in captivity since second part of 19th centry

had a large population to start with

behavior

morphology

appearance

physiolgy

development

floppy ear/curled tail

formed genetically centered view of animal domestication

showed that selection for tameness causes behavioral, physiological, developmental, and appearance changes

showed the paralles between behavior, physiology, and development changes observed between domestic animals and their wild progenitors

cross-breeding from tame and aggressive strains

cross-fostering pups from tame and aggressive moms

transplantation of embryos

233 rats

tame rats

had decreased anxiety-related behavior

lower levels of corticosterone

increased frequency of white spotting

height, weight, milk yield, time lenght of an exploratory activity, exit speed

(quantitative traits)

can be measured

number of offspring, number of attempts to find a maze exit

(Quantitative traits)

can be counted

genetic variation

environmental variation

gene-environment interation (GEI)

13-year long study of 5 dog breeds (Basenji, Beagle, Cocker spaniel, Shetland Sheepdog, and Wire-haired Fox terrier) from birth to ~1year

measured emotional reactivity (significant differene between breeds)

maze test, trainability, and aggression

MAOA is linked on X chromosome

MAOA breaks down seritonin

MAOA knockout mice more aggressive

ZZ-male

ZW-female

thought to be linked to Z chromosome

Cornish hens = broody

White Leghorn hens = not broody

cross Cornish M with Leghorn F is only way to get brood progeny

dull and bright rats raised in...

• standard lab environment: bright outperforms
• impoverished environment (no stimuli): poor performance of both
• enriched environment: same level of performance

behavior are complex phenotypes usually controlled by many genes

three sources of behavioral variation (genetics, environment, gene-environment interaction)

gene environment interactions may lead to unexpected results

(identical handling may have different effects on different genotypes (dogs))