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How can an octopus change color so quickly?

An octopus can alter the appearance of its skin far faster than a new coat of pigment could grow. Tiny structures already in the skin control what becomes visible, with pigment and reflected light playing different roles.

5–7 min

Questions you could explore

  • How do muscles change the visible area of a pigment sac?
  • How is reflecting light different from revealing pigment?

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Nature and biology

How does a honey bee dance give directions?

A returning honey bee can communicate about food without leading every other bee to it. The direction and duration of its waggle dance carry information that other bees can use beyond the dark hive.

3–5 min

How does a honey bee dance give directions?

Nature and biology3–5 minA returning honey bee can communicate about food without leading every other bee to it. The direction and duration of its waggle dance carry information that other bees can use beyond the dark hive.

Nature and biology

How do bats use echoes to find prey?

An echo can tell an echolocating bat more than whether something is nearby. The delay and character of returning sound help it follow a target as the encounter changes.

3–5 min

How do bats use echoes to find prey?

Nature and biology3–5 minAn echo can tell an echolocating bat more than whether something is nearby. The delay and character of returning sound help it follow a target as the encounter changes.

Nature and biology

What happens when a coral bleaches?

A coral can turn white while it is still alive. Bleaching involves a breakdown in its relationship with tiny photosynthetic partners, and what happens next depends on the stress and the opportunity to recover.

3–5 min

What happens when a coral bleaches?

Nature and biology3–5 minA coral can turn white while it is still alive. Bleaching involves a breakdown in its relationship with tiny photosynthetic partners, and what happens next depends on the stress and the opportunity to recover.

How can an octopus change color so quickly? | Speech Topic | speaking.app