Knees: Passive value

McGeerDiagrams_200w.jpgTad McGeer proved that you don’t need knees to walk downhill. But he also proved that downhill walking is nicer with knees.

He further proved that you don’t need a brain if all you want to do is walk down a slope. Nor do you need much else. Just a pair of legs – call them stand-alone legs, if you like – will do it.

McGeer proved these things mathematically. Then he proved them in a way that non-mathematicians seem to find more persuasive….

So begins this week’s Improbable Research column in The Guardian.