Tooth enamel is the hardest substance in the human body.
Enamel is about 96% mineral, harder than bone. But it has no living cells, so once it's damaged it can't grow back.
HISTORICAL ARCHIVE
Sources · October 30, 2026
Every claim from this day’s challenge, with its verdict, explanation and sources.
Round 1
A cockroach can live for weeks without its head.
It can, since it breathes through body openings and has nerve clusters beyond its brain — but with no mouth it can't eat or drink, so it eventually dies.
Earwigs crawl into your ears while you sleep to lay eggs in your brain.
Earwigs prefer cool, damp outdoor spaces under rocks and logs. The name stems from Old English superstitions; they do not nest in human bodies.
Round 2
The Hindenburg disaster was one of the first catastrophes captured on both film and audio.
Newsreel cameras filmed the 1937 fire, and Herbert Morrison's recorded radio report — "Oh, the humanity!" — aired the next day, making it instantly world-famous.
Apples, peaches, and strawberries are all roses.
All belong to the Rosaceae family — evolutionary cousins of the ornamental rose bushes in your garden.
Touching a baby bird makes its mother abandon it.
Most birds smell poorly and parent fiercely; a returned chick is almost always reclaimed by its mother.
Round 3
Your blood vessels could circle the Earth about 2.5 times.
~60,000 miles of arteries, veins, and capillaries in one adult versus Earth's 24,901-mile waistline.
An apple a day keeps the doctor away.
Not quite: a 2015 study found daily apple eaters visited doctors just as often — though they were slightly more likely to avoid prescription drugs.
Lava is the deadliest part of a volcanic eruption.
Most lava flows move slowly enough to walk away from, so deaths directly from lava are uncommon. Pyroclastic flows, volcanic mudflows (lahars), gases and explosions are far deadlier.