Beneath the land surface of the Bahamas, the underwater caves
known as blue holes stretch for hundreds of miles in all directions.
©2010 WGBH Educational Foundation
By LARRY SMITH
THE incredible blue holes of the Bahamas were featured in a one-hour NOVA documentary that aired on PBS-TV (channel 13 on cable) Tuesday night.
It was expected that the show would be seen by over 270 million households in more than 100 countries.
Titled "Extreme Cave Diving", the documentary is about cutting-edge science that gives important data on global climate and reveals new information about the Eden of now -extinct animals that once lived on the islands of the Bahamas.
NOVA is the highest rated science series on television and the most watched documentary series on American public television.
It is also one of television's most acclaimed series, having won every major television award, most of them many times over.
The documentary was co-produced with National Geographic, which sponsored a high-powered team of scientists, divers and filmmakers on an expedition around the Bahamas aimed at unlocking the secrets of blue holes.
Pelagomacellicephala iliffei
Discovered: 1985
Location: Caicos Islands
Size: 5-9 mm
This segmented worm was first sighted in a deep tidal pool within a blue hole. The species was named for biologist Tom Iliffe,
Discovered: 1985
Location: Caicos Islands
Size: 5-9 mm
This segmented worm was first sighted in a deep tidal pool within a blue hole. The species was named for biologist Tom Iliffe,
©2010 WGBH Educational Foundation
peonebalia cannoni
Discovered: 1995
Location: Bahamas, Caicos Islands
Size: 8-11 mm
Like many of the animals from these lightless caves, this small shrimp-like crustacean lacks eyes and pigment.
Discovered: 1995
Location: Bahamas, Caicos Islands
Size: 8-11 mm
Like many of the animals from these lightless caves, this small shrimp-like crustacean lacks eyes and pigment.
©2010 WGBH Educational Foundation
These geological features have been described as one of the final frontiers for human exploration on the planet.
Explorer
The expedition was led by Dr Kenny Broad, an ecological anthropologist at the University of Miami, and the production team included dive leader Brian Kakuk, probably the planet's top science and cave diver; Jill Heinerth, an internationally sought-after technical diving instructor; and director of photography Wes Skiles, arguably Florida's greatest cave explorer.
The research team included scientists like Dr David Steadman, curator of birds at the Florida Museum of Natural History in Gainesville; Jennifer Lynn Macalady, an astrobiologist from Penn State University who studies the origin of life; and Dr Tom Iliffe, a marine biologist from Texas A & M in Galveston whose work has led to the discovery of more than 250 new species in submerged caves around the world.
The expedition criss-crossed the Bahamas over six weeks from early June to mid-August exploring submerged caverns, conducting original research and producing spectacular videos and stills for print, broadcast, online and educational applications.
Expedition leader Kenny Broad (right), an anthropologist and expert cave diver, and Brian Kakuk, diving safety officer for the Caribbean Marine Research Center, prepare to delve into a blue hole. © Jill Heinerth/National Geographic Television
As a National Geographic-sponsored expedition, Bahamian blue holes are now in the same league as polar expeditions by Robert Peary, excavation of the lost Inca city of Machu Picchu, Louis and Mary Leakey's research into early hominids in East Africa, and underwater explorations by Titanic discoverer Robert Ballard.
The expedition's roots go back to 2004 when Brian Kakuk discovered the complete skeleton of an extinct tortoise in a blue hole called Sawmill Sink in the pinelands of south-central Abaco.
Later investigations in this undisturbed cave turned up a range of impressive fossils -- the prehistoric reptiles, birds, and mammals that once roamed Abaco.
Evidence
A few human bones were also found, and dated to about a thousand years ago. This is the earliest evidence so far for human occupation of the Bahamian archipelago.
But Sawmill Sink was only one of many blue holes around the country that the expedition explored.
After the initial discoveries at Sawmill Sink a few years ago, responsibility for the research was assumed by the Antiquities, Monuments and Museums Corporation (AMMC), with Marsh Harbour cave diver Nancy Albury appointed as the corporation's representative and project coordinator. According to Dr Broad, "Dr Keith Tinker, executive director of the AMMC, saw the potential in all this and it is primarily because of him that this expedition is taking place. Nancy Albury provided formidable help in both the filming and the science aspects."
New Species
By around 7,000 years ago, the polar ice caps melted to about their modern-day size and the sea level rose accordingly, flooding the blue hole caves in the Bahamas and elsewhere with saltwater. Marine biologist Tom Iliffe is pictured here with a new species.
By around 7,000 years ago, the polar ice caps melted to about their modern-day size and the sea level rose accordingly, flooding the blue hole caves in the Bahamas and elsewhere with saltwater. Marine biologist Tom Iliffe is pictured here with a new species.
©2010 WGBH Educational Foundation
NOVA producer James Barratt said the team was able to recover two skulls belonging to ancient humans, the fossils of vertebrates that are now extinct in the Bahamas, and fossils of birds that aren't just extinct but have never before been described by science.
Creatures
"Living within the blue holes are at least one new order of multi-cellular creatures, descended from animals that evolved millions of years ago, as well as single-celled organisms virtually indistinguishable from the first life-forms on Earth," he said.
"Parts of blue holes are like our planet's first seas, from a time four billion years ago when the Earth had no oxygen. NASA was interested in the expedition because the extreme life-forms found in blue holes are similar to what they hope to find on other planets.
"When cut open, stalagmites from blue holes display layers like the rings in a tree. Analysis of their composition reveals a year-by-year diary of the Bahamas' climate for the last 200,000-300,000 years, including rainfall, the chemicals in the rain and air, even the temperature. They don't just record past periods of extreme climate change, but also tell us how fast that change can grip the planet," Mr Barratt said.
In addition to the scientific discoveries, the documentary featured stunning images from deep beneath the islands of the Bahamas. Cave diving has been described as the most dangerous sport on Earth. In fact, the members of the Bahamas expedition have collectively recovered the bodies of more than 100 fellow cave divers during their hazardous careers.
National Geographic is expected to publish a major cover story on Bahamian blue holes this summer. Some 12 million people will read the magazine article, and millions of students will be exposed to Bahamas-related school materials. The Society's high-traffic website will feature linked coverage of the Bahamas expedition.
* The programme can be watched online at pbs.org or ordered from the site on DVD.
