Dating above your social class
One measure of infidelity is covert illegitimacy, a situation which arises when someone who is presumed to be a child's father (or mother) is in fact not the biological father (or mother).
Frequencies as high as 30% are sometimes assumed in the media, but research Such studies show that covert illegitimacy is in fact less than 10% among the sampled African populations, less than 5% among the sampled Native American and Polynesian populations, less than 2% of the sampled Middle Eastern population, and generally 1–2% among European samples.
According to The New York Times, the most consistent data on infidelity comes from the University of Chicago's General Social Survey (GSS).
Interviews with people in non-monogamous relationships since 1972 by the GSS have shown that approximately 12% of men and 7% of women admit to having had an extramarital relationship.
One measure of infidelity among couples is the frequency of children secretly conceived with a different partner, leading to "non-paternities".
Such covertly illegitimate children amount to about 1–2% of newborns in studied populations.
On the other hand, when people live within environments that encompass little stress and threats to the viability of offspring, the need for serious and committed relations is lowered and therefore promiscuity and infidelity are more common.In terms of infidelity, the theory states that when sex-ratios are high, men are more likely to be promiscuous and engage in sex outside of a committed relationship because the demand for men is higher and so this type of behaviour, which is desired by men, is more accepted.On the other hand, when sex ratios are low, promiscuity is less common because women are in demand and since they desire monogamy and commitment, in order for men to remain competitive in the pool of mates, they must respond to these desires.For example, one study found that some women in more financially independent and higher positions of power, were also more likely to be more unfaithful to their partners.These findings suggest there may be various factors that might influence the likelihood of some individuals to engage in extradyadic relationships, and that such factors may account for observed gender differences beyond actual gender and evolutionary pressures associated with each.