Your Definition Of Intelligence?
The subject of intelligence is complicated and debatable. What constitutes "intelligence", how it's measured, and what impact that it has is unclear, and sometimes touched with prejudice and racism.
Let's play devil's advocate for a second and assume that, no matter what "intelligence" is, it is a genetic element.
It would not be shocking, therefore, to notice a geographical spread of this attribute, just as different traits, like skin colour, build, resistance to certain diseases etcetera, have geographical spreads.
Intelligence Linked With Genetics?
This idea seems plausible when comparing it to other situations that have occurred. Most Europeans have light-coloured skin due to their environment and evolution. If intelligence had a genetic component in it, this same idea could be seen spread through a specific race.
But, what does this mean?
Why would having the ability to think in a specific way cause some theory that this makes one 'super' and another 'sub'?
No One Is Superior
Evolution isn't a ladder of superiority; it's merely a mechanism of change. This is often what we've turned into. It's no 'better' nor 'worse' than a bacteria or a blue whale.
Our intelligence has allowed us to dominate our surroundings, maximise our lifespans (for some of the species population, anyway) and exponentially increase our population.
Intelligence is what makes us dominate; it is what makes us humans. We are the dominant beings on Earth due to our intelligence; we are able to maximise life spans and exponentially increase our population.
The Harm We Cause Due To Our Domination
However, it also means that we are polluting the one planet we have access to. We have brought a great deal of inequality between members of our species on an arbitrary basis. It has also given us the means to destroy ourselves, probably taking a good slice of alternative species with us.
Is being 'more' intelligent truly 'better'? Are less intelligent people less human?