LECTURE 5

Question 1

What did Darwin learn from artificial selection?

Answer 1

1. breeders selected individuals with desirable traits
2. only selected individuals allowed to breed
3. selected individuals offspring showed desirable traits in greater proportion than the previous generation

Question 2

What is Darwin’s theory of evolution by Natural Selection?

Answer 2

1. individuals within a population differ from one another
2. variation is inherited
3. individuals vary in their success at surviving and reproducing
4. survival and reproduction are non-random
   - if all of these points occur, evolution should occur

Question 3

What was Darwin’s take on survival of the fittest?

Answer 3

Not those who were physically fit, rather those who were the best at adapting to environments

Question 4

How does natural selection operate?

Answer 4

1. natural selection acts on phenotypes, but changes observed in population
2. natural selection consists of changes in allele frequencies
3. natural selection does not anticipate future events
4. selection acts on existing traits
5. Natural selection does not to perfection, it leads to adaptation
6. natural selection is non random & not progressive natural selection increases environmental adaptations
7. selection acts on individuals not for the good of the species

Question 5

Can new traits not evolve under natural selection

Answer 5

false,
1. random mutations produces new alleles during reproduction in all species
2. meiosis & fertilization recombine existing alleles into new genotypes during reproduction in sexual species