Explain SMBC — the wiki for Saturday Morning Breakfast Cereal

The Joke

A woman is explaining the biological concept of "spandrels" to another person. In evolutionary biology, spandrels are traits that are not directly selected for by natural selection but instead arise as byproducts of other adaptations. She gives the example of species that are not especially adapted but came into existence as a byproduct of the "good stuff" of evolution -- genuine adaptation.

The conversation then takes a personal turn. The woman reveals that after researching spandrels, she started telling her husband he is "a spandrel" -- meaning he is not a carefully selected partner but rather a byproduct, a side effect of other life decisions. Her husband was initially excited that she was interested in biology, but became less enthused once he realized she was using it to insult him. The final panels show their marriage deteriorating further as she doubles down, telling him all the things they do together are "for the benefit of our relationship, but the spandrels theory suggests so much of the surrounding classes are mostly maptyings [adaptations]." The punchline lands when the husband, clearly defeated, just says "I love you too" as she continues her biological taxonomizing of their relationship.

The Humor

The humor derives from the classic SMBC trope of taking an academic concept and applying it with devastating literalness to personal relationships. The wife has weaponized evolutionary biology terminology to categorize her husband as an evolutionary accident rather than a deliberate choice -- which is simultaneously intellectually interesting and emotionally devastating. The comic also plays on the common dynamic where one partner becomes obsessed with a new idea and cannot stop applying it to everything, much to the other partner's dismay.

References

"Spandrels" in evolutionary biology comes from the famous 1979 paper by Stephen Jay Gould and Richard Lewontin, "The Spandrels of San Marco and the Panglossian Paradigm." The term was borrowed from architecture, where spandrels are the triangular spaces between arches that are structural byproducts rather than intentional design features. Gould and Lewontin argued that many biological traits are similarly byproducts of other adaptations rather than direct results of natural selection.