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How do you test a familiar story about evolution?

Peppered moths are a familiar example of changing color frequencies in a changing environment. Explaining the pattern requires more than showing light and dark moths on different backgrounds. A later field study addressed how moths were placed and observed, testing the role of bird predation while recognizing the limits of disappearance as evidence.

8–10 min

Questions you could explore

  • How could an experiment’s setup change what it appears to show?

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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
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
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
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