DAUPHIN ISLAND, Ala. — It was 6 a.m. at the dock on a Tuesday in December, and the weather did not look promising. Fog hovered over the water, and the engine of the Research Vessel E.O. Wilson rumbled.

Our ship disappeared into the mist, and by 7:30 the crew, a team of biologists, chemists and microbiologists, reached its destination. The sun lounged on obsidian water, masking a secret world where land and sea swap places, and past, present and future collide.

This is the underwater forest. Its unusual residents, shipworms and related marine organisms could serve as incubators of unexpected medicines, churning out new lifesaving formulas and compounds that may not be found anywhere else on the planet. But first the group of scientists had to manage to dive 60 feet beneath the ocean’s surface to recover their unusual subjects, a task made more challenging by three days of uncooperative weather.

“Underwater forest” is not a metaphor — this is not a coral reef or a sea grass bed that resembles surface woodlands but bona fide trees with roots and leaves. For thousands of years, this cypress grove lay silent, preserved within an oxygen-less tomb of sand and sediment. Then came Ivan.