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The Mitochondrial Eve Hypothesis suggests that the mitochondrial DNA of all living people can be traced back to a few women in Africa - VCE - SSCE Biology - Question 7 - 2011 - Paper 1
Question 7
The Mitochondrial Eve Hypothesis suggests that the mitochondrial DNA of all living people can be traced back to a few women in Africa. a. i. Why is mitochondrial DN... show full transcript
Worked Solution & Example Answer:The Mitochondrial Eve Hypothesis suggests that the mitochondrial DNA of all living people can be traced back to a few women in Africa - VCE - SSCE Biology - Question 7 - 2011 - Paper 1
Step 1
Why is mitochondrial DNA useful for tracking human evolutionary history?
Answer
Mitochondrial DNA (mtDNA) is useful for tracking human evolutionary history because it is inherited solely from the mother, meaning there is no mixing of genetic material from the father. This allows researchers to trace maternal lineages more accurately. Additionally, mtDNA has a higher mutation rate compared to nuclear DNA, which enables scientists to observe evolutionary changes over generations more effectively.
Step 2
Step 3
Based on these observations, what are two inferences that can be made about human evolution?
Answer
- Modern humans evolved relatively recently, indicating a common ancestor for all living humans who lived within a certain timeframe.
- The fact that the greatest variation in mitochondrial DNA is observed within African populations suggests that Africa is the cradle of humankind, from which modern humans migrated to other parts of the world.
Step 4
Explain why DNA analysis cannot be used to trace very early hominin (previously called hominid) ancestry.
Answer
DNA analysis cannot be used to trace very early hominin ancestry because DNA degrades over time, and the material from ancient hominins is often too degraded to yield usable genetic information. Additionally, the time span that has elapsed since the existence of early hominins makes it challenging to connect their DNA to modern species.
Step 5
Outline two types of evidence, other than DNA analysis, that can be used to determine the relatedness and age of early hominins.
Answer
Evidence 1: Fossils - The study of fossilized remains can provide insights into the physical characteristics and possible behaviors of early hominins. Evidence 2: Tools - The discovery and analysis of stone tools used by early hominins give clues about their cognitive abilities and how they interacted with their environment.