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What can a microphone hear beneath the sea?

A microphone beneath the sea can reveal activity that a person watching the surface would miss. Hydrophones record animal sounds alongside other underwater noise, giving researchers another way to investigate marine life. But a recording is not a head count: one animal may call repeatedly, while another remains silent. Detection depends on both the sound and the listening conditions.

3–7 min

Questions you could explore

  • How could you tell many calls from one animal apart from calls made by many animals?

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How does a honey bee dance give directions?

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How does a honey bee dance give directions?

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How can an octopus change color so quickly?

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Nature and biology

How do bats use echoes to find prey?

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3–5 min

How do bats use echoes to find prey?

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