body-heat
Explanation
The Joke
The comic plays on the popular myth that "you lose 90% of your body heat through your head." In the first panel, one person tells another this supposed fact, and the listener is surprised. The second panel shows a news anchor reporting that a physicist froze to death while running naked through a snow drift wearing only a polyester balaclava (a head covering). The physicist's last words were reportedly "Null hypothesis confirmed" — meaning she tested whether covering only the head would be sufficient to stay warm, and confirmed that the claim is false by dying of exposure.
The Humor
The humor works on multiple levels. First, the "90% of body heat through your head" claim is a well-known myth that has been widely debunked — the head loses heat roughly proportional to its surface area (about 10%), not 90%. The comic takes this to an absurd extreme by imagining a physicist who took the myth so literally that she designed a fatal experiment to disprove it: if you really lost 90% of heat through your head, covering just your head should keep you alive in extreme cold. The physicist's use of "null hypothesis confirmed" as her dying words is darkly funny because it frames her death in the dispassionate language of scientific methodology — the null hypothesis being that covering the head alone does not prevent fatal heat loss. It satirizes the stereotype of scientists who are so devoted to empirical rigor that they would literally die for a data point.