Challenge Questions
Section 26.3
Question 26.31
Explain why natural selection may cause prezygotic reproductive isolating mechanisms to evolve if postzygotic reproductive isolating mechanisms are already present but natural selection can never cause the evolution of postzygotic reproductive isolating mechanisms.
Question 26.32
Polyploidy is very common in flowering plants: approximately 40% of all flowering plant species are polyploids. Although polyploidy exists in many different animal groups, it is much less common. Why is polyploidy more common in plants than in animals? Give one or more possible reasons.
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