SortStack #671 — 2028-04-10

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. A red kangaroo (standing) 1.5 m

   Kangaroos cannot walk backwards, a trait so iconic it earned them a spot on Australia's coat of arms.

4. An orca (killer whale) 8 m

   Orcas have distinct dialects passed down through families, essentially regional accents that differ between pods.

5. A yellow school bus 13.7 m

   That specific shade, 'school bus yellow', was chosen in 1939 because it stays visible in dim dawn light.

6. A giant sequoia (tallest) 89 m

   These trees can live over 3,000 years, and their thick bark resists fire that clears competing plants away.

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