SortStack #2920 — 2034-06-07

By speed · Order from slowest to fastest.

1. The creep of a mountain glacier 175320 mm/year

   Glaciers flow downhill under their own weight like very slow rivers of ice, grinding valleys as they go.

2. A chicken foraging 3.6 km/h

   Chickens can recognise over a hundred individual faces, both other birds and the humans who feed them.

3. A striking barracuda 42 km/h

   Barracudas can lunge in sudden bursts to ambush prey, sometimes mistaking a swimmer's shiny jewellery for fish.

4. A bottlenose dolphin 60 km/h

   Dolphins sleep with half their brain at a time, keeping one eye open to breathe and watch for danger.

5. A record badminton smash 565 km/h

   The shuttlecock is the fastest object in any racket sport, though it decelerates almost as quickly as it launches.

6. A 5.56mm rifle bullet 3.1K km/h

   Small, fast rifle rounds tumble on impact, transferring energy in ways a slower, heavier bullet would not.

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