Twin study suggests rationality and intelligence share the same genetic roots - the study suggests that being irrational, or making illogical choices, might simply be another way of measuring lower intelligence.

[u/mvea]

https://www.psypost.org/twin-study-suggests-rationality-and-intelligence-share-the-same-genetic-roots/

[u/JahShuaaa]

Although the study featured a large sample of twins and made use of widely accepted methods to measure intelligence and rational decision making, there were some limitations and open questions for future research. The measure of rational thinking used only a few items and might not capture every aspect of how people make decisions in real-life contexts. Different tests, especially those involving larger sets of problems, could confirm or refine the results. It would also be useful to see how these findings play out in childhood and adolescence, as well as in different cultural settings. Future work could look for influences from personality traits, learning experiences, or motivational factors that might add further detail to how intelligence and rational decision making interact.

Beware of twin studies, they are deeply flawed. Intelligence and every other cognitive or behavioral trait are not predetermined by genes. Rather, our intellectual abilities are dynamic processes that develop over the lifespan and emerge via the interaction between an organism's physiology, the organisms that surround and interact with that organism, and the resources said organisms have access to.