Not all immigrants are the same. By Eric S. Raymond.

Castes in India have been maintaining almost perfect endogamy [marriage only to others in the same caste] for thousands of years. About the only significant category of exceptions is that if you have an exceptionally beautiful daughter you might succeed in getting her taken as a concubine by a higher-caste man, so their offspring might jump a rank.

With no significant gene flow between jatis [Hindu castes], divergences in important traits like IQ and time preference not only don’t smooth out, but actually amplify due to genetic drift and differing selective pressures.

Highest-caste Indians have an IQ distribution a lot like Europeans. Low-caste Indians…don’t.…

This doesn’t mean all low-caste Indians are stupid; Gaussian distributions don’t work that way. It does mean that importing 10,000 low-caste Indians has very different implications for the host society then importing 10,000 Brahmins.

Segue to the recent news stories about American families getting killed by illiterate Indian truck drivers doing crazy stupid things on the roadways. Those truck drivers are not Brahmins.

This is a recent phenomenon because, until one of our political parties decided to import the entire Third World for vote-farming purposes, we were cream-skimming India. Now we’re not, and this makes a serious difference.

Take note, Canberra.

A commenter makes a wider point:

India’s castes crash into America’s delusions of equality with confusing and devastating results.

The next step is to realize that America did the “cream skimming” thing to Europe at its founding. America has always been exceptional and in defiance of regression to the mean.