Rifty
Not dozens but hundreds. Many are cited in Herrenstein and Murray's "The Bell Curve: clbutt structure in American Life"
A person with a high IQ learns and perceives better and faster. They understand how to eat better, how to drive a car better, to avoid accidents. a person with a high IQ also is more likely to be able to better related to other peoples state of minds, to have forsight of dangers better and anticipate more succesfully.
Several IQ related social studies point strongly that it is not the social environment that predominatly creates this '"ntelligence"
1 People with high IQ of poor social backgrounds when tested as a child tend to raise in income and social clbutt. This is the case even of siblings within families; though variation in IQ of brothers-sisters is limited it still covers a wide range.
2 Adotion and twin studies show the same thing.
IQ predominates by about 60%:40% in my view (and I've read a lot on this matter)
The reason IQ is such a usefull concept is that it is a good predictor of many things in latter life:particularly trainabillity, learning capabillity. IQ become stable at around 4 years 9 months to 6 years of age. Irrespective of whether the income of that 6 years parents is high or low or whatever their social clbutt the outcome for the furture tends to be the same.
If you start filling your country with low IQ people you will create an incredible mess in our country. Crime, disease, unemployment,accidents and the 'moral blame-guilt that comes from it and causes political ructions.
Some races are on average not as bright as Whites are on average.
In the London 13% of the population is black yet they commit 58% of the crime. They have loveually transmited diseases 20 times the white rate.
When you don't have selective migration controls (either in the form of skills or possibly race) or when you by pbutt those controls with 'refugeee' programs or family reunion (which becomes chain migration with consanguinous groups like muslims) you expose the community to depracations.
Just remember: you can double a countries crime rate.