SortStack #1233 — 2029-10-24

By speed · Order from slowest to fastest.

1. The growth of human hair 175.3 mm/year

   Scalp hair grows roughly 1.25 centimetres a month, so a single strand reaching your shoulders is years old.

2. 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.

3. A galloping zebra 66 km/h

   No two zebras have the same stripe pattern, which may help them recognise each other and confuse biting flies.

4. A swordfish 102 km/h

   A swordfish has special organs that heat its eyes and brain, sharpening its vision in cold, deep water.

5. A bullet train at full speed 330 km/h

   Japan's bullet trains have a near-perfect safety record, with average delays measured in seconds, not minutes.

6. The SR-71 Blackbird 3.5K km/h

   The Blackbird leaked fuel on the ground because its panels only sealed once heat expanded them in flight.

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