FEATURE: Rain forests of Brunei hold secrets for biologists

Changes to the ecosystem may, for example, lead to the disappearance of frogs whose skin secretions could help cure cancer.

The rainforests have to stay intact to keep those possibilities alive.

“The rainforests provide all those free gifts — clean water and clean air,” Grafe said.

If the primary forests are cut down, the animals vanish.

Rainforests also help keep down pests like mosquitoes, which transmit diseases such as dengue fever.