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Replacing a feather that cannot repair itself

A mature feather is a dead structure, so a frayed flight feather cannot heal itself like living skin. Birds replace feathers through molting, with timing and sequence varying among species. Explore how losing and regrowing feathers affects flight and insulation.

3–5 min

Questions you could explore

  • What is the difference between a complete and a partial molt?
  • How could replacing feathers create different challenges for different birds?

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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 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

How can an octopus change color so quickly?

Nature and biology5–7 minAn 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.

Nature and biology

Finding prey through returning echoes

An echolocating bat uses the delay and character of returning sound to follow a target. Its calls can change as it approaches prey, connecting the sound it sends with the information it needs next.

3–5 min

Finding prey through returning echoes

Nature and biology3–5 minAn echolocating bat uses the delay and character of returning sound to follow a target. Its calls can change as it approaches prey, connecting the sound it sends with the information it needs next.

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