Sessile Mind

Cancer kills people. Chemotherapy, radiation and surgery often stop it. Biopsies identify it. Taking health advice from @DavidWolfe, @Luizmd, @JamieAA_Again, @ValerieAnne1970 and other internet’s undertakers can help cancer finish the job.

Desert ants find their nest by counting steps. Researchers glued stilts onto ants leaving the nest, and on the way back the insects walked straight past the entrance. Ants with shortened legs stopped short of it. Sent out again, both groups got it right.

Play the syllable ba over video of a mouth saying ga and most people hear da. Knowing how the illusion works does nothing to stop it. Close your eyes and the sound returns to ba, which shows that ordinary hearing had been using your eyes all along.

Before 1840 the person receiving a letter in Britain paid for it, priced by distance and by the number of sheets. Rowland Hill moved the charge to the sender at a single flat rate and volume more than doubled within a year. The stamp existed because refusing delivery was common.

Almost no bird makes blue pigment. A jay's blue comes from nanoscale structure in the feather barbs that scatters light. Crush the feather and the blue disappears, while a crushed red or yellow feather keeps its colour. Blue eyes get their colour the same way.

OK began as a joke. Boston papers in 1839 were printing deliberate misspellings as abbreviations, and oll korrect gave OK. It survived because Martin Van Buren's 1840 campaign adopted it for Old Kinderhook. A newspaper gag is now understood in nearly every language on Earth.

Nearly all intercontinental internet traffic runs through fibre optic cables lying on the seabed, some no thicker than a garden hose. Satellites carry a small share. When one breaks, a ship sails out, grapples it up from kilometres down and splices it by hand.

Caloric, phlogiston and the luminiferous ether all made accurate predictions before being abandoned. That pattern grounds an argument in philosophy of science: if past successful theories turned out false, success may be weak evidence that today's theories are true.

The banded iron that supplies most of the world's iron ore records the period when photosynthesis first pushed oxygen into oceans full of dissolved iron. The oxygen rusted the iron out of the water and onto the seabed. Steel today is mined from that ancient waste.

Red dwarfs burn hydrogen so slowly that their lifespans run into trillions of years. The universe is 13.8 billion years old, so not one has ever reached the end. Every red dwarf ever formed is still burning, and they make up about three quarters of all stars.

The library at Nineveh survived because it burned. Its texts were on clay, and the fire that destroyed the palace baked the tablets hard enough to last 2,600 years. The papyrus and parchment libraries that no fire ever touched are the ones we have lost.

Put a mark on a toddler's face and show them a mirror. Before roughly 18 months they reach for the mirror. After, they reach for their own face. About a dozen other species have shown the same shift, among them elephants, magpies and a small reef fish.

Many systems count time as seconds elapsed since 1970 stored in a signed 32 bit number. That counter runs out on 19 January 2038 and wraps around to 1901. The fix has existed for years, and the exposure now sits in devices being installed today that nobody plans to open again.

Every Cavendish banana is a clone of one plant, propagated by cuttings, seedless and genetically identical to the rest. The variety before it, Gros Michel, was destroyed commercially by a soil fungus in the 1950s. A new strain of that fungus is now moving through the Cavendish.

Stretch a rubber band against your lip and it warms. Let it snap back and it cools. Hang a weight on one and heat it, and it pulls the weight up instead of sagging. Its elasticity comes from the disorder of tangled molecules, so adding heat tightens it.

A 1973 audit of Berkeley graduate admissions found women admitted at a lower rate overall, while department by department they were admitted at a slightly higher rate. Women applied more often to departments that rejected nearly everyone. Both figures were correct.

Radiation that shatters the genome of Deinococcus radiodurans into hundreds of fragments does not kill it. Within hours it reassembles the pieces in the correct order. The repair system probably evolved to handle drying out, which breaks DNA in much the same way.

During the siege of Leningrad the staff of the world's first seed bank guarded a collection of edible seeds, rice, peanuts and potatoes. Several of them starved without touching it. What they were protecting was the harvests of countries none of them would live to see.

A rocket on the pad is around 85 percent propellant by mass. The structure holding it together is a few percent, thin enough that some designs would buckle under their own weight unless kept pressurised. The payload that reaches orbit is often under 4 percent of what lifted off.

Korean letters were designed in the 1440s to picture the mouth making the sound. The symbol for 'k' shows the tongue blocking the throat, 'm' shows closed lips, and an added stroke marks an added puff of air. Scholars opposed it for being learnable in a single morning.

Olympus Mons rises about 22 km above the Martian plains and covers roughly the area of Italy. Its slopes average a few degrees, so someone climbing it would walk uphill for days across ground that looks flat, with the summit staying below the horizon the whole time.