“LO OK,” MY SON SAID.

We were bobbing in the shadow of a pier on Isla

Vieques in Puerto Rico. Wooden slats a few feet

above our heads sheltered us from the tropical sun.

Weather-beaten pilings disappeared beneath the

water’s surface. It was cool there but barren—a

human-made spot suitable only for a quick rest

during our first foray into snorkeling.

Will pointed down. His eyes were wide behind his

mask. He dipped his head underwater. I followed.

We entered another world. Above the water the

pier was a dull structure of warped wood and chipped

paint. Underwater it teemed with life—orange and

yellow corals wrapping around the pilings, lush sea

plants undulating in the current, darting schools of

silvery fish. This narrow place beneath a dock built

decades ago for U.S. warships was as fecund as any

jungle—but unlike a jungle, we could float in the

midst of it and examine it from every angle.

BY RACHEL HARTIGAN

JACQUES-YVES COUSTEAU’S CO-INVENTION OF THE AQUA-LUNG OPENED
THE UNDERSEA REALM TO SCIENTISTS—AND A WONDERING PUBLIC.

L

IN THIS SECTION

Learning Numbers

The Benefit of Blue

Urban Wildlife Aid

Your Data’s Security

NATIONAL GEOGRAPHIC VOL. 241 NO. 3

EXPLORE

A Chance to

‘Become a Fish’

ILLUMINATING THE MYSTERIES—AND WONDERS—ALL AROUND US EVERY DAY

MARCH 2022 15