Unraveling the Mystery of the Ocean’s Twilight Zone

Deep down into the sea, 200 to500 feet belowthe surface, lifeforms flourishwhere they shouldn’t. Down here, little light penetrates, which is somewhatof a problem for solar-powered beings like coral. Yet here, stubbornly, the reefsstill sprawl, supporting hordes of fish and invertebrates, forming an ecosystem thats almost totally foreign to science. This is the mysterious twilight zone.

For a long time, researchers have considered this place too deep for traditional scuba diving and too shallow to justify exploring with expensive submersibles.But thanks to some fancy new technology, researchers at the California Academy of Sciences are beginning to dive to the twilight zone, observing and collecting its many bizarre denizens. And on Friday, theyre bringing the mysterious reefs to you and me with an unprecedented exhibit in San Francisco. If youre not one of the handful of people in the world trained to dive 400 feet deep( where the pressure is nearly 200 pounds per square inch, by the way) for seven hours at a time, this is your glimpse at one of countries around the world least-understood ecosystems.

Slide: 2 / of 8.

Caption: It’s a surprisingly complex ecosystem teeming with life.Kathryn Whitney/ California Acade