Evolution

Question 1

evolution

Answer 1

change in allele frequencies in populations over successive generations

Question 2

gene

Answer 2

“locus” (region) of DNA

Question 3

Alleles

Answer 3

alternative forms of the same gene

Question 4

Biological fitness

Answer 4

ability of an organism to produce surviving offspring

Question 5

Adaptation

Answer 5

heritable trait that increases the fitness of an individual in a particular environment compared to other individuals that don’t have this trait

Question 6

the 5 key mechanisms of evolution

Answer 6

• mutation
• genetic drift
• natural selection
• sexual selection
• gene flow

Question 7

what is the ultimate source of all genetic variation?

Answer 7

mutations

Question 8

effects of mutations

Answer 8

by changing the genetic code new alleles are generated which can…
- change amino acid sequences or alter gene expressions

Question 9

most mutations decrease

Answer 9

fitness

Question 10

genetic drift

Answer 10

random changes in allele frequency

Question 11

genetic drift is stronger in

Answer 11

smaller populations

Question 12

example of genetic drift

Answer 12

walking and randomly stepping and killing a bunch of bugs

Question 13

when do you expect strong effects of genetic drift?

Answer 13

population bottlenecks - when species go close to extinction

Question 14

when do you expect strong effects of genetic drift?

Answer 14

founder effect: new island - first few animals arrive on island and repopulate

Question 15

Natural selection was discovered by

Answer 15

Charles Darwin and Alfred Wallace

Question 16

Natural selection is the idea that

Answer 16

traits that improve survival/reproduction should increase in frequency through time

Question 17

Example of natural selection in nature

Answer 17

Daphne Major drought

Question 18

Daphne major drought

Answer 18

• drastic ecological changes led to a decrease in seed abundance
• little soft seeds dried out and only the hard large seeds were left
• high mortality of darwin finches because all their food was gone
• finches with larger beaks were more likely to survive
• traits are heritable: relationships between beak size of parents and off spring

Question 19

intra-sexual

Answer 19

male-male competition

Question 20

inter sexual

Answer 20

female choice

Question 21

natural and sexual selection often act in…

Answer 21

opposition to each other

Question 22

Gene flow

Answer 22

movements of genes among populations

Question 23

gene flow tends to oppose divergent

Answer 23

natural selection