The first member of their party started down into the funnel-shaped cave and spotted something unusual — a dog. “He said, ‘Whoa! There’s a dog down here!’” Rochette said.

Rather than the way most caves form, which is from the top down with carbonic acid. This cave formed from the bottom up. There is the release of hydrogen sulfide gas. It's what we call rotten egg ...

The first member of their party started down into the funnel-shaped cave and spotted something unusual - a dog. "He said, 'Whoa! There's a dog down here!'" Rochette said. "And I asked if it was ...