Toxic caverns teaming with strange life-forms spark a brand new theory about how caves form.

For nine months in 2000, Tom Hart Dyke was a captive of guerrillas who seized him while he was collecting wild orchids in the Colombian rain forest. Now Hart Dyke is at it again in the most orchid-rich and one of the most politically unstable parts of Irian Jaya, the western half of the island of New Guinea.