Dr. Thomas Iliffe of Texas A&M at Galveston, who specializes in cave biology, has discovered more than 250 new species of marine cave-dwelling animals in his years exploring underwater caves around the world. Because he is a pioneer in his field, most papers in his discipline are either authored by him or cite his work.
Of special interest to him are inland, anchialine (from Greek, literally “near the sea”) and offshore, marine caves. Anchialine caves, called blue holes in the Bahamas and cenotes in Mexico, are on land near the coast, but still have fully marine waters at depth.
Some, like those he explored on the Yucatán Peninsula, contain creatures that date back to before the meteor impact that wiped out the dinosaurs 65 million years ago. Originating in the sea, ancestors of today’s cave species colonized subterranean systems and were then cut off from their parent populations.
Brought to light by Iliffe and his team after spending millions of years evolving in darkness and isolation, they represent many lost primitive forms that persisted only in the deep interior of saltwater caves. Like the coelacanth, these “living fossils” can give us key insights into the evolution of the modern forms that inhabit the sea today and possibly represent missing links in our knowledge base of life on Earth.
Now, researchers are involved in a race against human development and pollution to explore these caves and document their unique life before they are lost. Several sponges in these caves have shown potential in developing pharmaceuticals that are resistant to cancer and aging. Since many of these new and unique species are found only in a single cave, pollution or destruction of the cave habitat would result in their complete extinction.
These white, blind creatures, mostly crustaceans, have lost all their original pigmentation and often their eyes as well, as the sense of sight would be completely useless in the total darkness. They can provide insight into how life survives in extreme environments where light is absent and food and dissolved oxygen are in short supply. More than that, the study of similar forms inhabiting cave systems on opposite sides of the Earth can show us how they evolved from a common ancestor to adapt to varying conditions.
This past August, supported by a grant from the Biotic Surveys and Inventories Program of the National Science Foundation, Iliffe and three of his graduate students explored caves in the central Bahamas at Eleuthera Island. The island is about 220 nautical miles south west of Miami, and is about 100 miles long by one mile wide.
The purpose of this expedition was to collect and identify cave species as the first step to conservation. Possible caves and sinkholes were located with the help of Google Earth satellite images. To locate and explore them often meant hiking through dense brush and poison wood trees, carrying heavy dive gear, prior to diving down into inky, unexplored blackness. The collected specimens have been sent to labs around the world for identification. Initial results indicate at least several new species are present.
For information, go to cavebiology.com.
By Amber Tull and Glenn Burnett
Source: Galveston Daily News
