Science Update - Peppers and Pacemakers

Bob - This week for The Naked Scientists, I'm going to talk about a possible source of energy that has scientists all abuzz. But first, Chelsea's going to talk about the food that fueled one culture of the past.

Chelsea - If you could travel back in time to the Mexico of a thousand years ago, the food would probably have a familiar kick to it. This according to archaeo-botanist Linda Perry of the Smithsonian's Museum of Natural History. She and her colleagues discovered well-preserved scraps of domesticated chili peppers in an ancient Mexican shelter cave. The peppers date back five to fifteen hundred years. Perry was struck by the variety: ten different kinds of peppers in all, including seven in a single location.

Linda Perry (National Museum of Natural History): Because you're not going to be growing seven different kinds of peppers if you're not making some really interesting food.

Chelsea - What's more, she says the peppers appear to have been used in both fresh and dried forms - providing a broad spectrum of spices that could fuel dishes similar to today's Mexican specialties.

鲍勃-谢谢,切尔西。好了,提示e music!

Forty years ago, good vibrations were giving the Beach Boys excitations. Now, Steve Beeby of the University of Southampton in England is using vibrations to generate real electricity. He's developed devices as small as a sugar cube that you stick on any vibrating surface. The vibrations jiggle a few strategically placed magnets, which surround a copper coil.

Steve Beeby (University of Southampton): So the coil's stationary and the magnets are moving. And that way you build up an electromotive force in the coil, which is basically a voltage.

Bob - It's a low voltage, but Beeby says it's enough to run small wireless sensors that monitor the structural integrity of machines and bridges. And in theory, it could even power a battery-free pacemaker just from the pulse of a patient's heartbeat.

Chelsea - Thanks, Bob. We'll be back next time to talk about some surprising things some bugs and plants do to protect their families. Until then, I'm Chelsea Wald...

Bob - ...and I'm Bob Hirshon, for AAAS, The Science Society. Back to you, Naked Scientists!