Scientists identify eight previously unknown species in underground cave near Ramle
Scientists discover an independent ecosystem in the cave that isn't based on photosynthesis.
Underground, beneath the surface of the Nesher quarry in Ramle, lies a cave with a vast array of calcite burrows, almost three kilometers long. For millions of years, the only sound interrupting the silence was the gentle scurrying of small, blind, colorless creatures, completely unaware of the world above them.
Before the quarry became active, the cave and tunnels were situated about 100 meters under ground level. In 2005, the first rays of light invaded the burrows, when a quarry bulldozer happened upon them. Scientists arriving at the scene, to research what they swiftly termed the "Ayalon Cave," discovered a unique form of life existing nowhere else on the planet: eight unknown species of crab, other arthropods and an eyeless scorpion.
The scientists shipped the creatures to labs throughout the world and now, six years on, the first part of the research is over, after most species were identified and described.
The scientists discovered an independent ecosystem in the underground cave that isn't based on photosynthesis. Since there was no light in the cave, or other known biological processes, the organisms in the cave were dependent on a process known as chimeotothropia which exists in other areas on earth, such as the bottom of the ocean.
The most important factors in the ecosystem are sulphur bacteria that, lacking light, evolve through a different chemical process. "All the nutrition systems within the cave are based upon these bacteria," says Hanan Dimentman from the Hebrew University of Jerusalem, who led the biological research in the cave. "There are creatures that eat the bacteria, those who devour the bacteria eaters, and there's the carnivores."
Due to their isolation, the creatures evolved into unique species which exist nowhere else on the planet. In fact, they are evolutionary remains of life that became extinct millions of years ago. The largest earth species discovered was the Israchanani scorpion, named after the two researchers of the cave, Yisrael Naaman and Hanan Dimentman.
The largest water creature found there evolved from a crab that roamed the Mediterranean Sea several million years ago. The water species thrive in a small pool in the cave's largest hall, 40 meters high. The pool consists of salty groundwater containing sulphur.
Prof. Amos Frumkin, director of the Hebrew University's Cave Research Unit in the Geography Department, explains that all the burrows were formed by the groundwater. "The cave was created in a completely different fashion than other caves we're familiar with, since water that contained hydrogen sulfide rose from a few hundred meters deeper. Since the water is acid, it dissolved the calcite rock."
The cave and burrows remained intact for millions of years under a 100 meter rocky envelope, but the quarry's mining work wore it down and now it's only a few dozen meters thick. "The cave is now at the center of an active mining area, which isolated the cave from all directions, leaving it as a sort of mountain in the middle of the quarry," Frumkin says.
After the quarry is fully exploited, existing plans intend the area to be flooded by streams feeding the Ayalon river, to prevent the river being flooded. If that happens, Dimentman says, "it could destroy the whole ecosystem of the cave and the aquifer surrounding it. We must defend our ecological system for the next generations. Not everything must be measured by the needs of our generation."