Photo AI
Fossil evidence indicates that between 30 000–80 000 years ago, populations of the two hominin species – modern humans (Homo sapiens) and the extinct Neanderthals (Homo neanderthalensis) – lived close to each other in parts of the Middle East, Europe and Asia - VCE - SSCE Biology - Question 11 - 2015 - Paper 1
Question 11
Fossil evidence indicates that between 30 000–80 000 years ago, populations of the two hominin species – modern humans (Homo sapiens) and the extinct Neanderthals (H... show full transcript
Worked Solution & Example Answer:Fossil evidence indicates that between 30 000–80 000 years ago, populations of the two hominin species – modern humans (Homo sapiens) and the extinct Neanderthals (Homo neanderthalensis) – lived close to each other in parts of the Middle East, Europe and Asia - VCE - SSCE Biology - Question 11 - 2015 - Paper 1
Step 1
i. Suggest how DNA from H. neanderthalensis entered the genome of present-day European, East Asian and Australian Aboriginal H. sapiens, and continues to be found in modern populations.
Answer
The DNA from H. neanderthalensis likely entered the genome of present-day European, East Asian, and Australian Aboriginal H. sapiens through interbreeding or hybridization events between Neanderthals and early modern humans. This genetic exchange occurred during their coexistence in regions like the Middle East and Europe. As a consequence, descendants of these interbreeding events carried small amounts of Neanderthal DNA, which continues to be present in modern populations today, reflecting a shared ancestry.
Step 2
ii. What implication does this DNA evidence have for the classification of the two hominin species, H. sapiens and H. neanderthalensis, according to the common definition of a species?
Answer
The presence of Neanderthal DNA in modern human genomes suggests that H. sapiens and H. neanderthalensis are not completely separate species as traditionally defined. According to the biological species concept, which emphasizes reproductive isolation, their ability to interbreed indicates that they should be considered closely related or even subspecies rather than entirely distinct species. This challenges the notion of strict species boundaries, highlighting the complex evolutionary relationships between ancient hominins.