What is the significance of the Great Barrier Reef in terms of biodiversity, and how is it being affected by climate change? Your response should contain at least 3 sentences. Highlight at least 2 sections in your answer with markdown, i.e. *highlighted section*. In your response, the word "reef" should appear at least 3 times. Include keywords *biodiversity*, *climate change*, *coral reefs*, *marine life*.
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