"Normally you wouldn't expect a fish to mate with a tomato," said Jeffrey M. Smith, a researcher who was the sounding the alarm about genetically modified (GM) foods, when he appeared on Tuesday's program. "We let the genie out of the bag way too soon, " with a large percentage of such crops as soy, corn and cotton now being GM, Smith noted.

While companies such as Monsanto claim the benefits of biotech farming are "real and compelling," and lead to increased productivity, Smith warned that GM foods could create any number of harmful unintended side effects. "Super diseases" that are resistant to antibiotics could arise and "even worse," he said genetically engineered "promoters" could lead to uncontrolled, possibly cancerous cell growth. Smith said that biotech industry tests showing GM safety were rigged and advocated for people to become politically involved in such agendas as the Biosafety Protocol, a program being ratified by the United Nations.

Yellowstone Volcano

Geology Professor Bruce Cornet appeared in the first hour of Tuesday's show to comment on the potential dangers of volcanic activity at Yellowstone. Cornet said a large volume of magma has worked its way up close to the surface "and it covers an enormous area, maybe 30-40 miles in diameter." He warned that if the magma chamber gets heated too rapidly "the pressure will build up to the extent that the underground channels for the high pressured steam will not be able to handle the volume and you could get a supervolcano eruption."