This may start out seeming to be racist, as it shows differences between races but is actually intended to show that such differences are a consequence of culture, including the white privilege that exists in Western societies.
Standard IQ tests consistently show average IQs, by race as Asian 106, White 100, African American 85 and Sub-Saharan Africans 70. Remember that this is averages. There are very bright, and very intellectually challenged people in all races.
There are many reasons for the observed differences in scores in IQ tests. Such tests repeatedly show racial differences but this does NOT mean that any race is inherently more intelligent than another.
The primary reason is culture. If an IQ test is developed by someone who is a member of the most dominant race in a Western society and then applied to someone from outside that group then they will fare badly. Different cultures have different ways of thinking, different histories to call upon, and different language structures.
Actual intelligence is the result of the interplay between genetics and environment. The environment element includes the physical and the cultural environments around us. These directly affect the development of the human brain. That brain is a living thing and needs nutrients in order to develop and grow. It is also a marvelous mechanism that adapts itself to its physical environment. Babies are not simply born with small brains that get bigger as a child grows. The developing brain is constantly strengthening connections that are stimulated by the environment in which the child is living and pruning away connections that are not used.
That the developing brain loses functionality that is not used is demonstrated by two cases. In the 1960's, horrible experiments were performed on kittens. Some of them were born and raised in carefully controlled environments. Those environments were constructed so that the growing kittens only ever saw vertical lines. When fully grown, the adult cats were never able to detect horizontal lines, at all, although other cats raised in varied environments could. Other experiments involved sewing closed one of the kittens eyes for the first three months of their lives. When the cats eyes were unstitched they were never able to see in the eyes that had been covered from birth. They remained always blind. These experiments, that led to a Nobel Prize, were carried out by Hubel and Wiesel.
The other case is that of Romanian orphans. During the communist regime in Romania, thousands of orphaned children were dumped in what were called orphanages but which were little more than holding cages. Most children were starved of affection and attention. These children were severely damaged. There is even a Romanian Orphan Syndrome that describes them. Bereft of emotional interaction they can not form such attachments in later life. The degree of impacts depends on how long they remained in this brutal, inhuman system. If rescued early enough then some semblance of normality is possible. but for many it was too late. See here: https://www.washingtonpost.com/local/romanian-orphans-subjected-to-deprivation-must-now-deal-with-disfunction/2014/01/30/a9dbea6c-5d13-11e3-be07-006c776266ed_story.html. The children's development was severely affected in many areas, from physical to intellectual, as well as emotional.
Another indicator of brain plasticity is increasing success at exams and, in IQ scores themselves. People today are far more intelligent, according to exam and IQ tests, than those born a century ago. The average US IQ is increasing at the effective rate of 3 points a decade and the standard tests are amended regularly to keep the average US IQ at 100. In Britain, the pass rate for Advanced level exams, that children who stayed on a voluntary extra two years take, is increasing year on year. The exams are assessed as not getting any easier but children are appear to be getting smarter. Genetically, there has not been enough time for greater intelligence to have simply evolved. What appears to be happening is that children today are thinking differently. It is easy, for someone my age, to see why. When I was a child, we had three TV channels and went to the library once a week. Access to information and different ideas was limited compared to day. Yes, there have always been intelligent people who had access to books to study but, for the majority of people, long work days meant that such access was more limited. Then along came the internet and devices that could connect to it. The more wealthy among the world's population suddenly had access to a deluge of information, news and new ways of thinking, explanations, argument and counter argument. As I write, I have a device in my pocket that can give me access to all the world's greatest philosophers, to expert explanations of everything from evolution to oncology to cosmology. Gone are three TV channels, that occasionally showed black and white, poorly hand drawn diagrams, and instead we have regular science shows that reveal, with sophisticated computer graphics, the working of the cosmos and our own DNA.
As well as getting far greater stimulation, our brains have recently had much better building material. Without nutrients, a brain that has the genetic blueprint for high intelligence is no more able to build that intelligence than an architect with a blue print for a sky-scraper is able to build a new World Trade Center with a small pile of bricks. Developing brains need calories and nutrients. According to the fossil record, human intelligence only really took off once we came down from the trees - as a result of drying out of the African forests - and began to eat the carcasses of other animals out in more open terrain. It follows that lack of access to adequate nutrition will have a powerful negative impact on brain development. One study looked at Korean children being adopted by American families. When those Korean children had experienced low nutrition in their home countries, they performed as average Americans on standard IQ tests, once they had started to consume an average American diet. However, crucially, they did less well than those Korean children who had not experienced malnutrition.
See: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2776771/
Much research has shown a link between diet and violence. Poor diet leads to more criminality. No, not all crime is linked to diet but the effect is significant. This shows directly that diet affects brain function.
http://www.theguardian.com/politics/2006/oct/17/prisonsandprobation.ukcrime
We can see then that stimulation and nutrition are critical components in the development of the human brain. The question then is, do all human children have equal access to good nutrition and to an environment that stimulates their development. The answer is an obvious no! It is estimated that 1 in 5 US children is under nourished. See: http://www.feedingamerica.org/hunger-in-america/impact-of-hunger/hunger-and-poverty/hunger-and-poverty-fact-sheet.html.
Poverty restricts access to food and to stimulation. Poor people are less likely to have access to the internet, are more likely to be either hungry or to have to depend on calorie rich, nutrient low cheap junk food.
The US Census of 2010 revealed levels of poverty among different races. 11% of people who identified as White only were beneath the poverty line. When it came to Black Americans that figure was more than double! 25% of Black Americans were living below the poverty line in 2010/
It takes little analysis to realize that if double the number of Black people than White are living in poverty then because of poverty's direct impact on brain development, more of the former group will be negatively affected, lowering the average IQ.
The reasons for Black poverty are two fold: Racism now and racism of the past. Numerous studies have shown that racism still stifles Black progress and opportunity today. Individuals with names perceived to be associated with Black culture are shown to have lower success when it comes to obtaining jobs http://cla.auburn.edu/econwp/archives/2014/2014-06.pdf.
Poverty of the past was also tied to racism and directly impacts children today because their parents were exposed to the lower stimulation and nutrition. they therefore have significantly lower opportunities for employment and provision of nutrition and stimulation to their own children.
Genetically, human beings are unusually similar, the world over. "The subspecies of the chimpanzee that lives just in central Africa, Pan troglodytes troglodytes, has higher levels of diversity than do humans globally, and the genetic differentiation between the western (P. t. verus) and central (P. t. troglodytes) subspecies of chimpanzees is much greater than that between human populations." In other words, a chimpanzee living in Central Africa is more different from another chimpanzee also living in Central Africa, than I am from an Aboriginal Native of Australia. This indicates that humans nearly died out and that we are all descended from a small group that survived.
Unless they have some medical problem, all people on Earth have the same genetic inheritance and potential. What they do not have is the same opportunity. Many start in poverty, descending from others who lived in poverty. Poverty has a direct effect on the brain, which governs how the lives of people will play out. Yes, people overcome hardships but for some, the dice are more loaded. Not everyone has the same opportunities.
The difference in opportunity for proper nutrition and mental stimulation explains the differences in IQ scores between groups. The average person in sub-Saharan Africa has lower nutrition, higher poverty and less access to mental stimulation than someone living in the comfortable, predominantly white West. In the US, there are many white people who experience poverty. However, minority groups are disproportionately impacted and have the added handicap of discrimination to contend with.
All children should receive adequate nutrition at school: Meals, milk and vitamin supplements for the very poor would solve many of the country's problems, allow all individuals, of whatever race, to achieve their potential.
