Associations between Climate and IQ in the United States of America

Abstract

Relations between average temperature of each of the 48 contiguous states and estimates of state IQ were inspected. Additional state variables were controlled in the correlational analyses, namely gross state product, percent Hispanic, Black, and Asian in the state population, and the pupil-to-teacher ratio for each state. A significant correlation between average temperature and state IQ was found (r = -.70, p < .001). Possible explanations are discussed.

Parasite prevalence and the distribution of intelligence among the states of the USA

“…Ryan et al, 2010). Currently, the southeastern states in the USA have higher percentages of Blacks than states in other regions do.…”

“…It should be noted that temperature, which has previously been considered to be an evolutionary variable (e.g. Templer & Arikawa, 2006) has been found to correlate negatively with average state IQ (Ryan, Bartels, & Townsend, 2010). We did not include this variable for two reasons: (1) Ryan et al (2010) did not attempt to explain why this relationship exists, so we cannot treat temperature as a causal variable, and (2) temperature is known to positively influence infectious disease (e.g.…”

“…Templer & Arikawa, 2006) has been found to correlate negatively with average state IQ (Ryan, Bartels, & Townsend, 2010). We did not include this variable for two reasons: (1) Ryan et al (2010) did not attempt to explain why this relationship exists, so we cannot treat temperature as a causal variable, and (2) temperature is known to positively influence infectious disease (e.g. Guernier et al, 2004), so by controlling for temperature we would, in part, be controlling for infectious disease.…”

Geographic Models of Socioeconomic and Cognitive Development: A Test in Peru

“…Cognitive ability declines with proximity to the equator between countries [53,63] and within such countries as Italy [58] , Japan [35] , Peru [44,51] , Russia [28] , Spain [59] , Sudan [3] , the United States [20,45,46,74,86] , and Vietnam (Kirkegaard & Pesta, 2018), although not in Turkey [60] nor India [64] . The exceptions may be accounted for by the greater longitudinal than latitudinal extension of Turkey and the fact that Mus-lims, whose IQ is lower than the IQ of followers of other faiths [57,92] , are more concentrated in the northern regions of India (Basant & Shariff, 2010).…”

Updated IQ and Well-being Scores for the 50 U.S. States

“…Much research has resulted from McDaniel's (2006) estimates. Some of the state variables that IQ correlates with include government effectiveness (McDaniel, 2006), crime, education, health, and income (Pesta, McDaniel, & Bertsch, 2010), UV radiation (Leon & Hassall, 2017), climate (Ryan, Bartels, & Townsend, 2010), U.S. presidential election results (Pesta & McDaniel, 2014), religiosity (Reeve, 2009), and global well-being (Pesta et al 2010).…”