Lesson 4 - New evidence for evolution

Question 1

how can you use the mutation rate as a ‘molecular clock’

Answer 1

the more mutations there are in the DNA from 2 individuals, the longer the time since they had a common ancestor, so you can estimate how long ago the common ancestor lived

Question 2

what is the issues of using mutation rates for evidence for evolution

Answer 2

DNA starts to degrade immediately after death. Also, the rate at which different parts of the DNA mutates can vary, so the evidence has to be viewed under caution

Question 3

why has human evolution always been difficult to investigate

Answer 3

there’s only limited fossil evidence

Question 4

why is it important to use evidence from traditional studies (appearance, behaviour) as well as evidence from modern DNA and protein studies

Answer 4

as the same evidence can be interpreted differently

Question 5

describe how peer review is used to make a submitted article reliable

Answer 5

the article is read by a number of experts, who could potentially carry out the same evidence to validate its conclusion

Question 6

describe how scientific conferences are useful

Answer 6

• helps promote the development of new techniques in research
• provides opportunities to challenge the validity of results
• helps the exchange of ideas, data and techniques between scientists