The overlapping geography of cognitive ability and chronotype

Chronotype and cognitive ability are two human phenotypes with an uneven geographic distribution due to both selective migration causal environmental effects. In our study, we aimed examine the relationship between variables, chronotype. We used a large anonymized sample (n = 25,700, mostly from USA, UK, Canada Australia) of dating site users estimate chronotype questionnaire responses using item response theory. matched each user coordinates city size reported locations databases. line previous research found that male sex, younger age, residence in more populous locale, higher westward position within same time zone were associated later Male latitude ability, but effect population on was only present USA. The age stronger males, males older participants. Population density had independent association not Our results confirm ability. These findings generalize across countries, they moderated by suggesting biological cultural