“Blue Holes” are beautifully complex, intricate, underwater sinkholes that provide a deeper understanding of everything from geology, water chemistry, biology, paleontology, archaeology, and even astrobiology—the study of life in the universe. The August 2010 issue of National Geographic did a story on a number of the holes located in the Bahamas, and as one explorer put it, “I can think of no other environment on Earth that is so challenging to explore and gives us back so much scientifically.” Here are some selected excerpts with a link to the full article:
Ascending slowly to a depth of 60 feet, we pause at a sloping ledge directly below the cave mouth. In the middle of the ledge is a long trough packed with silt. Kakuk [Brian, one of the world”s foremost cave divers] spotted this promising feature on an earlier dive and now reaches into the mud. He gropes gently back and forth and—so quickly it seems miraculous—extracts a long bone the color of mahogany: a human femur. Two smaller bones follow. Then he extends his arm deeper, working the silt, and draws out the domed pate of a human skull. Although lacking a lower jaw, the yellowed skull has molars on both sides and a single front tooth. The forehead slopes dramatically, a sign that its owner was a member of the native Lucayan tribe that thrived in the Bahamas from the sixth through the 15th centuries. To create a sloping brow, Lucayans bound boards to their children”s foreheads. Some archaeologists think the practice was intended to make the front of the skull better able to withstand blows in battle; others believe it was purely aesthetic.
“One of the things we know about the Lucayans is that they were tremendous divers,” Pateman tells me. “They were sought out by the Spaniards to dive for pearls. And we”ve found evidence of deep diving on some of the skulls—over time, in response to the pressure, bone builds up around the ears.” As with so much in the scientific study of blue holes, Pateman”s work has barely begun. Foremost on his mind is the question: How and why did Lucayans end up in blue holes? He suspects that the mobile games gratis submerged caves were burial sites, but the discovery of a bound Lucayan body in a dry cave on one island suggests other, more violent practices. Were they murder victims? Were they victims of feuding, warfare, or religious sacrifice?
Lucayan bones are just part of the tapestry of blue holes, says Nancy Albury, project coordinator at the National Museum of the Bahamas, whose passion for blue holes centers on the animal remains they contain—the remarkably preserved fossils and bones of crocodiles, tortoises, bats, owls, beetles, and other species that thrived in the Bahamas before the Lucayan occupation. “In some blue holes,” Albury says, “we”ve found complete skeletons and soft tissues preserved on tortoise shells thousands of years old. Leaves still have their structure and pigments, and insect wings are still iridescent blue and green.” As expedition paleontologist Dave Steadman explains, the anoxic, sheltered environments of blue holes are perfect for preserving organic material. Were it not for blue holes, Steadman says, much of the fossil record for Bahamian animals going back thousands of years would not exist.
To read the full story, visit Bahamas Caves
