Hiccups result from involuntary contraction of the diaphragm—a reflex with no clear evolutionary purpose, lasting 5-60 seconds. The contractions produce a repetitive clicking sound. Frequency varies by individual and circumstance; amplitude is usually subtle. Yet audio engineer Dr. Gary Rodriguez recorded hiccups from the man in 2000 at a social event and performed spectral analysis. The frequency spectrum matched acoustic signatures of distant thunder—a phenomenon requiring sound pressure levels above 100 decibels. Yet Rodriguez's proximity measurement showed the man standing casually, no obvious exertion. Rodriguez's hypothesis: "Hiccups are normally involuntary and weak. His diaphragm, operating at full musculature capability even during involuntary reflex, produces acoustic output equivalent to a natural phenomenon."

Most bodily functions operate at partial capacity. Some bodies don't know how to do anything halfway.