Larger organisms are equally interesting to scientists. Most are colorless and cannot see. For example, the Agostocaris cave shrimp is only about two and a half centimeters long. It has no color except an area of its digestive system. Then there is the remipede. Some scientists describe it as a living fossil. It has changed very little over the past three hundred million years. Remipedes are less than five centimeters long, but they are fierce. They use their poisonous teeth-like fangs to kill shrimp and other creatures.
BARBARA KLEIN: Blue holes also permit scientists to study climate change over thousands of years. They want to understand what those changes could mean in the future.
Some of the horizontal caves have calcite formations called stalagmites and stalactites. They formed little by little tens of thousands of years ago when sea levels dropped. Scientists can study these formations and map out the climate conditions present during every year of their growth.
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STEVE EMBER: Because blue holes contain no oxygen, they also protect ancient objects from the destruction of time. For example, divers in Sanctuary Blue Hole on the island of Andros in the Bahamas found the ancient bones of native Lucayan tribe members. Experts are not sure whether this tribe placed bodies in caves as part of burial ceremonies or for other reasons.
Animal remains are also preserved in excellent condition. Divers in Sawmill Sink on Abaco Island found the three-thousand-year-old remains of a Cuban crocodile. This kind of crocodile has long disappeared from the Bahamas. They also found some ancient turtle skeletons. They were so well preserved they still had pieces of soft tissue.
最新
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25