SortStack #3550 — 2036-02-27

By speed · Order from slowest to fastest.

1. A slowly marching sand dune 20161.8 mm/year

   Wind pushes desert dunes forward grain by grain, swallowing roads and even villages over the decades.

2. A three-toed sloth 240 m/h

   Sloths move so slowly that algae grows in their fur, giving them a greenish camouflage in the canopy.

3. A person jogging 10.8 km/h

   Humans are among the best endurance runners on Earth, able to outlast horses over very long distances in heat.

4. A gray squirrel 19.5 km/h

   Squirrels plant thousands of trees by accident, forgetting where they buried many of the nuts they hid.

5. A running reindeer 80 km/h

   Reindeer eyes change colour with the seasons, turning blue in winter to see better in the dim Arctic light.

6. A missile warhead on re-entry 24K km/h

   An intercontinental missile arcs into space before plunging back down, its warhead glowing from the friction.

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