In his 2010 paper, “Why Liberals and Atheists Are More Intelligent”, Kanazawa stated :
When our ancestors faced some ambiguous situation, such as rustling noises nearby at night or a large fruit falling from a tree branch and hitting them on the head, they could attribute it either to impersonal, inanimate, unintentional forces (wind blowing gently to make the rustling noises among the bushes and leaves, a mature fruit falling by its own weight from the branch by the force of gravity and hitting them on the head purely by accident) or to personal, animate, intentional forces (a predator sneaking up on them to attack, an enemy hiding in the tree branches and throwing fruits at their head).
Given that the situation is inherently ambiguous, our ancestors could have made one of two errors of inference. They could have attributed the events to intentional forces when they are in fact caused by unintentional forces (false-positive or Type I error) or they could have attributed them to unintentional forces when they were in fact caused by intentional forces (false-negative or Type II error). The consequences of Type I errors were that our ancestors became unnecessarily paranoid and looked for predators and enemies where there were none. The consequences of Type II errors were that our ancestors were attacked and killed by predators or enemies when they least suspected an attack. The consequences of committing Type II errors are far more detrimental to survival and reproduction than the consequences of committing Type I errors. Evolution should therefore favor psychological mechanisms which predispose their carriers to commit Type I errors but avoid Type II errors, and thus overinfer (rather than underinfer) intentions and agency behind potentially harmless phenomena caused by inanimate objects. Evolutionarily speaking, it is good to be paranoid, because it might save your life (Haselton and Nettle 2006).
Recent evolutionary psychological theories therefore suggest that evolutionary origin of religious beliefs in supernatural forces may stem from such an innate bias to commit Type I errors rather than Type II errors. The human brain may be biased to perceive intentional forces (the hands of God at work) behind a wide range of natural physical phenomena whose exact causes are unknown. If these theories are correct, then it means that religion and religiosity have an evolutionary origin. It is evolutionarily familiar and natural to believe in God, and evolutionarily novel not to be religious.
Then, if the precautionary principle, so often despised by economists, is evolutionarily familiar, it appears that this attitude is highly beneficial because this will improve our reproductive success. As such, ideology like liberalism is maladaptative; by promoting unnatural attitude, it tends to decrease our reproductive success, unless the relation has been distorted by government’s laws (an example of this is provided by Kanazawa & Savage, 2009, p. 122). This is why liberalism correlates with higher IQ, and this is why high IQ is detrimental. Not surprising if the so-called “racism” correlates with low IQ. Given the precautionary principle, it is natural to distrust strangers. Again, this is because the consequence of Type II errors (thinking that the danger is not there when it is) does not worth the risk.