SortStack #190 — 2026-12-16

By speed · Order from slowest to fastest.

1. The growth of a cave stalactite 0.1 mm/year

   Most stalactites lengthen by less than a tenth of a millimetre a year, dripping mineral by mineral over millennia.

2. A mosquito in flight 2.4 km/h

   Only female mosquitoes bite; they need a blood meal to develop their eggs, while males sip flower nectar.

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 red fox 51 km/h

   Foxes may use Earth's magnetic field to aim their pounces, lining up on prey hidden under snow.

6. A racing greyhound 76 km/h

   Greyhounds reach their top speed in just a few strides and spend much of a sprint completely airborne.

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