Keratin, the substance wool, hair, and feathers are made from, makes a pretty thin diet, but the clothes moth has been dogging humanity's closets and drawers for hundreds of years, unravelling the work of generations of knitters and weavers to feed its larvae.Martha has a personal beef with the moth and talks with Curt Stager about the life cycle of the moth, and how to fight its ruinous effects.
Porcupine quills are hollow, like feathers, and are made from the same material, but then so are hairs, and fingernails, and claws and scales. The quill is a unique adaptation of one of nature's commonest substances and it varies even among porcupines.African porcupines can weigh as much as 60 pounds and have quills as thick as soda straws. Martha Foley and Dr. Curt Stager talk about "prickly" matters.
Why does the moon look bigger when it's on the horizon?
Why does the moon look bigger when it's on the horizon, than it does when it is high in the sky? Curt Stager shoots down all of Martha Foley's theories.There are a couple ways it could be a trick of the mind, but why then doesn't it work all the time? After physics, optics, geometry and psychology, what are you left with? "Wow, big moon."