AniSci Exam #1 (Animal Domestication)

Definition of Domestication

A process whereby populations of animals change genetically and phenotypically (behavior & physiological), driven by selection pressure (natural, artificial, unintentional) based on human-desired traits

Reasons for early domestications. Why did humans utilize wolves, and then domesticate dogs?

Reasons:

• economic and religious purposes

• food, clothing, and labor

Utilized and domesticated dogs by adapting to the wolf’s way of hunting alongside them, then achieving too much meat, and would give it to the animals which led to domestication

Pre-adaptations- When starting the domestication process, what traits did they look for? Why?

• docility

• generalist feeder

• social

• promiscuous or polygamous mating

• non-territorial

• ecologically flexible

How does Animal Behavior correlate with wild animals and domesticated animals?

Wild animals: Forces of evolution

Domestic animals: Forces of evolution AND natural, artificial, and relaxed selection

How do we evaluate fitness? Why is fitness important?

Fitness is important because animals with high fitness pass on more genetic material to next generation

• did animal survive? (Locates food, shelter, avoids predation)

• how many offspring did animal have? (Locates males, reproduce, care for young)

Domestication successes & failures- Why did they or didn’t work?

Stages of Domestication : How many stages are there and what are they?

5/6

• didn’t care much about humans, interbreeding w/ wild was common, and animals closely resembled wild forms

• controlled breeding to prevent breeding w/ wild, selection for small size, docility, and reduced fear of humans and tolerance of confinement

• increase size of animal but not change behavior

• selection for desired traits increased and breeds were developed

• wild ancestors hunted to near extinction to protect the artificially selected stock 

• relaxation of natural selection is more pronounced with modern intensive agricultural practices

What changes have we seen in domestication? What hasn’t changed?

What has changed:

• Losses in fitness

• Cognitive mechanisms (reduced responsiveness to changes in environment) 

• Neoteny (retention of juvenile features in an adult animal) 

• Size and coat color differences

What hasn’t changed:

• Change in behaviors

How does Genetic Mechanisms influence the domestication process?

• Inbreeding (results in increased homogeneity) 

• Genetic drift (genes may be fixed by chance in small population)

• Artificial selection (concious selection-goal oriented)

What is feralization?

basically, the reversal of domestication

What are the differences between wild, domesticated and tame?

Domesticated: permanent genetic modification that can lead to predisposition to associating with humans

Tame: conditioned behavioral modification at the individual animal level

Wild: have not been altered by humans

What are the forces of evolution?

• Natural selection

• Mutation

• Random drift

• Gene flow between populations