Explain SMBC — the wiki for Saturday Morning Breakfast Cereal

The Joke

In this comic, a character (likely a child) asks why their fingers get pruney in the bath. The parent or adult gives a scientific explanation — that fingers wrinkle in water as an evolutionary adaptation to improve grip on wet surfaces. But instead of being satisfied, the child (or the adult themselves) spirals into an existential or theological tangent, connecting the "intelligent design" of pruney fingers to broader questions about religion and science.

The comic plays on the common experience of bath-time pruney fingers but uses it as a springboard to satirize the tension between scientific and religious explanations for natural phenomena. Zach Weinersmith frequently uses mundane everyday observations as entry points into much deeper philosophical or scientific territory, and this comic follows that pattern — taking something as trivial as wrinkled fingers and escalating it into a debate about the nature of design in biology.

The Humor

The humor comes from the absurd escalation — a perfectly innocent, everyday question about pruney fingers gets blown up into a much larger conflict between science and religion. This is a classic SMBC comedic technique: taking a small, relatable moment and extrapolating it to ridiculous philosophical extremes. The comedy also relies on the gap between the mundane trigger (bath wrinkles) and the grandiose conclusion.

The red button/votey panel likely adds an additional punchline that further extends or subverts the joke, as is typical for SMBC's bonus panels.

References

• Aquatic wrinkling: The scientific explanation that finger wrinkling in water is an active nervous system response (not just osmosis) and may be an evolutionary adaptation for gripping wet objects. This was notably studied in a 2013 paper published in Biology Letters.
• Intelligent design vs. evolution: The comic touches on the ongoing cultural debate between evolutionary biology and the intelligent design movement, which argues that certain biological features are best explained by an intelligent cause rather than natural selection.