Detailed Instructions: Write an inquisitive question about a specific text span in a given sentence such that the answer is not in the text.
Q: Sentence: Like Darwin ’ s finches or Great Britain ’ s peppered moths , these hedgehogs of the sea increasingly embody nature ’ s stunning capacity for resilience .<sep>Span: hedgehogs of the sea
A:
Why are sea urchins known as hedgehogs of the sea?