Unit 3-Lesson 2

Question 1

What is the concept of survival of the fittest?

Answer 1

• The concept was introduced by Herbert Spencer
• This phrase “Survival of the fittest” has been used to describe Darwin’s theory

Question 2

What are 4 types of selection?

Answer 2

• Directional Selection
• Stabilizing Selection
• Disruptive Selection
• Sexual Selection

Question 3

Describe directional selection

Answer 3

Selection that favours an increase or decrease in the value of a trait from the current population average

• study diagram -

Question 4

Describe stabilizing selection

Answer 4

Selection against individuals exhibiting traits that deviate from the current population average

• study diagram -

Question 5

Describe disruptive selection

Answer 5

Favours two or more variations of a trait that differ from the current population average

Question 6

What is a human example of disruptive selection

Answer 6

Human Example: some population have adapted to living at extreme heights that are able to survive despite lox oxygen levels

Question 7

Describe the sexual selection

Answer 7

The favouring of any trait that specifically enhances the mating success of an individual

Question 8

List the characteristics artificial selection

Answer 8

• A controlled, captive breeding process
• Occurs in captivity rather than in wild
• Human chose which individuals to breed that demonstrate a favourable trait

Question 9

What is the process of artificial selection

Answer 9

• Choose a species that can be bred in captivity
• Breed a large number of individuals
• Choose a trait that you wish to favour
• Identify individuals that exhibit this trait most strongly
• Breed only these individuals to produce the next generation
• Repeat steps 4 and 5 over many generations

Question 10

What is artificial selection in plants?

Answer 10

• Domestic crops are bigger and heartier than wild
• Selection process takes over thousands of year - beginnings in the fertile crescent

Question 11

What is artificial selection in animals?

Answer 11

• In animals, there are a number of features we may consider
  
  • Size
  • Muscle mass
  • Fattiness
  • Temper