SortStack #666 — 2028-04-05

By speed · Order from slowest to fastest.

1. A person walking 5 km/h

   The average person takes around 7,000 steps a day, walking the equivalent of several times around Earth in a lifetime.

2. A swarming desert locust 14.5 km/h

   A single locust swarm can contain billions of insects and devour as much food in a day as tens of thousands of people.

3. A gray squirrel 19.5 km/h

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

4. A striking barracuda 42 km/h

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

5. A common swift in flight 113 km/h

   Swifts can stay airborne for nearly a year without landing, even sleeping on the wing high above the ground.

6. A record tennis serve 270 km/h

   The fastest serves leave the racket so quickly the returner must react before the ball has even crossed the net.

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