scandinavia
Explanation
The Joke
The comic begins with someone asking whether it concerns the listener how much social science is based on data from Scandinavian countries. The other person responds that Scandinavians keep the richest data, and no other countries provide such detailed metadata. The first person then asks: what if Scandinavians are just weird, and if we study only them, we might think their quirks are universal? The response is "How so?"
The punchline is a fake journal cover for "nature" showing the headline: "Twins Separated at Birth Always Like Pickled Fish." This is a parody of twin studies -- a staple of behavioral genetics research -- combined with the stereotype that Scandinavians (particularly Swedes and Norwegians) have a strong cultural affinity for pickled herring and other preserved fish. The "finding" that separated twins both like pickled fish sounds like a profound nature-over-nurture discovery, but it is actually just a Scandinavian cultural trait being mistaken for a universal human one.
The Humor
The humor targets a real methodological concern in social science: the over-reliance on data from WEIRD (Western, Educated, Industrialized, Rich, Democratic) populations, and Scandinavian countries in particular, which maintain exceptionally thorough population registries. The comic exaggerates this bias to its logical absurd extreme -- if you only study Scandinavians, you will "discover" that all humans inherently love pickled fish. The fake "nature" journal cover is the perfect vehicle for this joke, lending an air of scientific authority to what is obviously a cultural preference rather than a biological universal.
References
The comic references the well-known critique in psychology and social science about WEIRD sampling bias, articulated prominently by Henrich, Heine, and Norenzayan in their 2010 paper. Scandinavian countries like Denmark and Sweden are frequently used in social science research because they maintain comprehensive national registries that allow researchers to track entire populations over time. Twin studies, which compare identical twins raised apart to disentangle genetic and environmental influences, are a classic research design in behavioral genetics.