SortStack #965 — 2029-01-29

By size · Order from shortest to longest.

1. A single grain of pollen 40 µm

   Pollen grains have survived intact for millions of years, letting scientists reconstruct ancient forests from lake-bed sediment.

2. A ladybird beetle 1 cm

   A single ladybird can eat 5,000 aphids in its lifetime, making it a gardener's favourite predator.

3. The Gateway Arch, St. Louis 195 m

   Its elegant curve is a catenary, the exact shape a hanging chain makes, flipped upside down for strength.

4. The Strait of Gibraltar (narrowest width) 14.4 km

   It is so narrow that on a clear day you can see Africa from Europe across the water.

5. The Yellow River, China (length) 5.5K km

   Nicknamed 'China's Sorrow', its devastating floods have killed more people than perhaps any other natural feature.

6. The Amazon River (length) 6.4K km

   It discharges so much water that it freshens the Atlantic Ocean more than 100 kilometres out from its mouth.

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