WES C. SKILES / NATIONAL GEOGRAPHIC IMAGE COLLECTION (MAIN IMAGE, CAVE
WATER, CRUSTACEAN); ANDREW HOUNSLEA / GETTY IMAGES (BLUE HOLE IN BELIZE)During past ice ages—the
most recent about 18,
years ago—water levels dropped
and new land was exposed. A mixture
of rain and soil ate away at the land,
forming holes that became deep
caves. The caves filled with water
after sea levels rose again. The
deepest known blue hole is
about 990 feet deep.HOW BLUE
HOLES FORMEDThe most amazing find in the blue holes? Human skeletons.
Scientists think the remains date back about 800 years to
the time of the Lucayans—the first people believed to live
in the Bahamas. No one is sure how the bones ended up in
the submerged caves. But the team thinks the Lucayans
might have used these areas as burial sites for their dead.
With more investigation, the mystery of the skeletons may
soon be solved. But scientists believe that other secrets are
waiting to be uncovered in blue holes. “There are hundreds
left that no human has seen,” Broad says. “It’s a whole other
world for exploration.”CLUES ABOUT UNDERWATER CAVES.
BONE-CHILLING DISCOVERY
OF THEE
BLUE HOBLUE HOLESLES
FANGED
CRUSTACEANA BLUE HOLE OFF BELIZE