SortStack #1919 — 2031-09-10

By speed · Order from slowest to fastest.

1. A swimming seahorse 1.5 m/h

   The dwarf seahorse is the slowest fish on record, fluttering a tiny fin dozens of times a second to barely move.

2. A casual cyclist 12.5 km/h

   The bicycle is one of the most efficient machines ever made, turning muscle into distance better than walking.

3. A koala on the run 30 km/h

   Koalas sleep up to 22 hours a day because their eucalyptus diet is so low in energy and mildly toxic.

4. A sea lion swimming 38 km/h

   Sea lions can be trained to detect underwater mines and even retrieve objects for navies.

5. A charging black rhinoceros 54 km/h

   A rhino's horn is made of keratin, the same material as your hair and nails, not bone.

6. A powerful soccer free kick 132 km/h

   A well-struck free kick can swerve in mid-air as spin and airflow bend its path around a defensive wall.

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