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How does my energy use differ if I walk, jog or run for 1 kilometre?

A reader weighs in on this one 鈥� and finds it will depend on how far you鈥檙e travelling

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Why don鈥檛 dogs look up when a low-flying plane passes overhead? part 2

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This week鈥檚 new questions

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2Y4D845 Dartmoor, Devon, UK. 17th Sep, 2024. Full Harvest Supermoon shines bright over Hay Tor on Dartmoor, Devon, UK. The September full Moon is often called the Harvest Moon due to its association with autumn harvests in the Northern Hemisphere. Credit: nidpor/Alamy Live News

What changes will occur on Earth as the moon moves further away?

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H99WWH Low Angled portrait of a German Shorthaired Pointer dog.

Why don鈥檛 dogs look up when a low-flying plane passes overhead?

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PF9N2P Honeybee stick on a window

Are flies following a strategy when they keep hitting windows? Part 3

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B0729K Television and cartoon characters, depicted in the form of toy dolls, making up a window display.. Image shot 03/2008. Exact date unknown.

This week鈥檚 new questions

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DDPTRF Hot air balloons at Balloon Fiesta in balloon fiesta Albuquerque, New Mexico, U.S.

Is it true that fresh air heats up faster than stale air? If so, why?

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D73X1R An colorful adult midnight snapper swims over the reef

How do fish recognise others of their own species? Part 2

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PF9N2P Honeybee stick on a window

Are flies following a strategy when they keep hitting a window? Part 2

Readers take issue with a former answer to this question, arguing for the different behaviour of wasps and flies 鈥� and for a more defined plan of escape than has previously been posited

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This week鈥檚 new questions

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How do fish recognise others of their own species?

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How many known elements could we delete without ill effect? Part 2

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This week鈥檚 new questions

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