"Human beings are doom riders," said author and thinker Howard Bloom in his appearance on Wednesday's show. "We are masters of disaster, and if we fail to realize that, we're in trouble," he continued. While our planet is on the verge of various environmental catastrophes, Bloom argues that nature "throws us curves and challenges us to overcome them," which in turn helps us to evolve.

There's only one family tree on this planet, said Bloom, and that's DNA. And in spite of any oncoming disaster, "DNA wins," because "it's covered its bets any way it can." For example, in the event of a nuclear war, some bacteria would thrive in the radioactive fallout. Cockroaches will survive too, he added with a chuckle.

"The next thing for us to come up with is defeating disaster before it happens," Bloom said. To prevent a worldwide drought for instance, he suggested harnessing natural forces such as tides, the advanced use of hydroponics and "giant eggbeaters in the sea."

Structures off Cuba

Investigator Linda Moulton Howe appeared in the first hour of Wednesday's program, reporting on a set of unusual megalithic stones found off the coast of Cuba that resembled architecture. They "can't be explained in natural geology," said Linda, who listed such shapes as triangles, pyramids and curved surfaces as showing up in the sonar images.

Linda interviewed Paul Weinzweig, co-owner of Advanced Digital Communications International, who was involved in the deep ocean bottom discovery. He told her that National Geographic had expressed interest in a preliminary survey of the structures before they would commit to a more extensive examination. To view photographs and read more details check out Linda's report on Earthfiles.com.