QUESTION 7 (4 marks)
a) Explain how habitat fragmentation can lead to speciation.
[3 marks]
b) Identify the type of speciation that occurs due to habitat fragmentation.
[1 mark]
QCAA guide · typeset solution
QCAA sample response and mark allocation
7a) | Habitat fragmentation can lead to geographic isolation, where populations that were previously able to interbreed can no longer reach each other to do so. This disruption to gene flow can result in two populations evolving independently to the point that they are too genetically dissimilar to interbreed. | • recognises that habitat fragmentation can cause populations to become isolated [1 mark] • identifies that this disrupts gene flow [1 mark] • explains how disruption to gene flow can lead to speciation [1 mark] |
7b) | Allopatric speciation | • identifies allopatric speciation [1 mark] |
QCAA sample response and marking criteria reproduced from the official guide.
Compare your working with the guide above.