Premise: Concealed and protected against atmospheric changes for 17,000 years, these awe-inspiring frescoes and engravings of bulls, horses, ibex, bison, and deer were discovered by four teenagers chasing a dog in 1940.

Hypothesis: The 17,000 year-old frescoes and engravings were subject to rain, wind, and other atmospheric changes that made them difficult to identify.
Relation: contradiction