Comparison with sequences outside caves is difficult because few caves are found in landscapes where there are comparable pollen records from lakes and bogs.
What you need to be prepared: You'll need headlamps for everyone in your party, and for the caves with more difficult entry and exit access, such as the Boy Scout Cave, hard hats or helmets come in handy.
Like many other geologic features concealed beneath the earth, caves are difficult to observe.
The assertion by William B. Eimicke, a Columbia professor, that "Mark Green would have caved" on difficult policy issues ("Under Bloomberg, Giuliani's Name Is Sacred, but Giuliani's Policies Are Another Story," news article, June 16), is ridiculous, baseless and belied by facts.
Building a reliable chronology for cave art is difficult because the primary dating method, the radiocarbon technique, is not suitable for engravings or paintings made purely with mineral pigments.
Indeed, the cave is very difficult to explore because an underground river keeps many of its galleries flooded.
To even get to that point takes months of dedicated training, practice, and experience, and access to cave sites is difficult.
It is this woman, known to the family as Precious Auntie, the bonesetter's daughter of the title, who has learned from her father the art of healing with bones dug from caves that are difficult to find and dangerous to enter.
Pearce adds: "The Scaloria Cave, with its difficult-to-access lower cave, was clearly a special place for the people of the Tavoliere, and we may imagine that it was thus a suitable place for final death rituals".
Vieira was five days into what was touted as one of the most difficult caving trips on Vancouver Island last October.
