At the end of an inconspicuous two-lane road near the city of Beaverton, Ore., a cluster of modest concrete-and-glass buildings nestles amid ponds, fields and magnificent groves of evergreens--an oasis of natural beauty standing firm against the encroaching suburbs. Only a pair of football-field-size enclosures surrounded by 9-ft.-high sheet-metal walls and monitored from a watchtower give the hint that this is something more than just an unusually idyllic office park. The huge pens suggest a dinosaur paddock from Jurassic Park--an image reinforced when whatever is inside inexplicably starts slamming violently against the metal walls.
But while the creatures housed at...