Grade 11 University Biology Unit 3 Evolution

Grade 11 University Biology – Unit 3 Evolution Dogs and More Dogs Nova Films – Classic Video Section 7.2 Artificial Selection

All species, including humans, exhibit genetic variation. Mutations are the primary source of genetic variation. Mutations create new genes that offer a supply of new genetic information. There are three general types of mutations: 1. Neutral mutation is a mutation that does NOT result in any selective advantage or disadvantage 2. Harmful mutation is any mutation that reduces the reproductive success of an individual, and therefore, it is selected against. Harmful mutations do NOT accumulate over time. An example is a mutation resulting in a genetic disorder such as cystic fibrosis. 3. Beneficial mutation is any mutation that increases the reproductive success of an individual (i.e., they give an individual an advantage). Beneficial mutations are favoured by Natural Selection and accumulate over time.

Artificial selection is directed breeding in which individuals that express a particular trait are chosen as the parents of the next generation. Artificial selection is used to produce new breeds or varieties of plants and animals. Artificial because it occur in a controlled setting. Selection because humans choose the traits that are desired and the parents that are bred.  The most unexpected result of artificial selection was the production of individuals exhibiting traits far beyond natural variability  Artificial selection can reduce genetic diversity within a population. If it is desired to eliminate a trait, artificial selection may offer a solution.  Artificial selection CANNOT produce traits that do not already exist in some form within a population.  Harmful mutations can be controlled (i.e., breeders would not select for a harmful trait)

Watch the movie and answer the following questions. 1. When the dog first domesticated?

2. What animal is the ancestor of the domestic dog?

3. Roy Coppinger thinks the “Adoption Theory” is unlikely. This theory suggests you could bring a wild animal into a domestic situation and raised as it is a pet. What is Coppinger’s alternative theory regarding the domestication of wolves?

4. What was the desired trait that was selected for according to Coppinger?

5. Why would this trait give wolves an advantage? Explain.

6. What is unusual about the patchy coats and curly tails of modern dogs?

7. How did these unusual traits appear? Explain

8. According to the fossil record, when were dogs and humans found together?

9. When were different sized dogs (breeds of dogs) first seen?

10. What is the theory of the development of the Saluki breed?

11. What is REGULATORY DNA?

12. What are the consequences of having purebred dogs?

13. Why did doge become so popular in the 1800s in England?

14. How did appearance become more of a focus (i.e., important traits to be selected for) over behavioural traits?

15. How has studying dogs that have been highly inbred been helpful to humans?

16. List some “jobs” humans have given to dogs Answers 1. When were dogs first domesticated? 15,000 years ago

2. What animal is the ancestor of the domestic dog? Wolf (Canis lupus)

3. Roy Coppinger thinks the “Adoption Theory” is unlikely. This theory suggests you could bring a wild animal into a domestic situation and raised as it is a pet. What is Coppinger’s alternative theory regarding the domestication of wolves? Wolves “chose” domestication as a source of “easy food”

4. What was the desired trait that was selected for according to Coppinger? Being less afraid of humans

5. Why would this trait give wolves an advantage? Explain. Access to food...with more food, more offspring...results in the reproduction of more tame offspring

6. What is unusual about the patchy coats and curly tails of modern dogs? Trait was human selected...conscious selection. Wolves do not exhibit this trait

7. How did these unusual traits appear? Explain Less adrenaline --- production of other hormones that controlled the tail trait

8. According to the fossil record, when were dogs and humans found together? 10,000 years ago 9. When were different sized dogs (breeds of dogs) first seen? 5,000 years ago

10. What is the theory of the development of the Saluki breed? Breed / “reward” the dog that catches the “rabbitt”

11. What is REGULATORY DNA? It tells the DNA what to do

12. What are the consequences of having purebred dogs? Genetic disorders

13. Why did doge become so popular in the 1800s in England? Status

14. How did appearance become more of a focus (i.e., important traits to be selected for) over behavioural traits? Once everyone in England had dogs, the rich needed a way to set their dogs apart

15. How has studying dogs that have been highly inbred been helpful to humans? Identify genes that cause anxiety

16. List some “jobs” humans have given to dogs Herding Tracking Hunting Support (guide dog; landmine / bomb detection) Labour (sled dog) Identification (drug sniffing; chemical sniffing)