Latest Pupa Gilbert Stories
To survive in a tumultuous environment, sea urchins literally eat through stone, using their teeth to carve out nooks where the spiny creatures hide from predators and protect themselves from the crashing surf on the rocky shores and tide pools where they live. The rock-boring behavior is astonishing, scientists agree, but what is truly remarkable is that, despite constant grinding and scraping on stone, urchin teeth never, ever get dull. The secret of their ever-sharp qualities has puzzled...
MADISON -- While the shiny material of pearls and abalone shells has long been prized for its iridescence and aesthetic value in jewelry and decorations, scientists admire mother-of-pearl for other physical properties as well. Also called nacre ("NAY-ker"), mother-of-pearl is 3,000 times more fracture-resistant than the mineral it is made of, aragonite, says Pupa Gilbert, a physicist at the University of Wisconsin-Madison. "You can go over it with a truck and not break it - you will crumble...
- Like a worm in form or movement; vermiform; tortuous or sinuous; also, writhing or wriggling.
- Like the track or trace of a worm; appearing as if worm-eaten; vermiculate.
- Marked with fine, close-set, wavy or tortuous lines of color; vermiculated.
- A form of rusticated masonry which is so wrought as to appear thickly indented with worm-tracks.