GED

Question 1

What three sets of rule did Darwin set for natural selection?

Answer 1

· Heritable characters (realising this was not simple!)
* Characters vary between individuals
* Differential fitness= survival and better adaptation between individuals

Question 2

Define Evolution

Answer 2

Genetic change over time in a population

Question 3

What does natural selection operate on, phenotypes or genotypes?

Answer 3

Natural selection operates on phenotypes, not genotypes

Question 4

Describe and explain the results of the experiment in the culture shown on the right.

Answer 4

· Selection pressure at 1 (antibiotics), large part of bacteria population dies
· Some mutate due to selection pressure and adapt to 1% antibiotic level
· Majority of population is dead due to antibiotic so less competition for mutated bacteria which have more resources so quickly reproduce and pass on alleles to future generations
· Increase in allele frequency over time
Process repeated as antibiotic percentage increases

Question 5

What characteristic of a whale may suggest that it evolved from a animal on the land?

Answer 5

Whales= Whales are mammals and also breathe air ‘among fishes’. Normally mammals are found on land, however, whales are mammals that live in the deep seas which strongly suggest they evolved from mammals on the land.

Question 6

• How did whale’s ancestors adapt to live in the seas?

Answer 6

· Whales closest relative e is a hippo which lives on land/ponds but is clearly a terrestrial mammal
· Common ancestor starts going back in the water
· Overtime they start losing limbs adapting to seas to swim better, better adapts more likely to survive and pass on gene

Question 7

Explain in details what the missing link is and how it proves evolution.

Answer 7

Explain in details what the missing link is and how it proves evolution.

Question 8

What is an example of bad design of evolution and how does this prove evolution?

Answer 8

· Left recurrent laryngeal nerve
· Branches from the vagus nerve in the brain to larynx
· By going from the vagus nerve in the brain all the way down to aorta just to come up back again (pointless if seen from an engineer point of view?)
· Controls voice box
· By supplying all the intrinsic muscles for the larynx

· Distance from brain to larynx= 30 cm
· Length of laryngeal nerve= 100 cm

So why so long and a long route when it could have been way shorter?
· We descend from fishes/amphibians which didn’t have necks for example, so it was looped around their ‘aorta’ which was nearby
· Larynx evolved from branchial arch, innervated by 4th branch of vagus nerve
* Left recurrent laryngeal nerve maintained its position while the function of the branchial arch changed over time