(2001) Thompson et al., conclude in their own words that, "A genetic continuum was detected in which brain structure was increasingly similar in subjects with increasing genetic affinity. Genetic factors significantly influenced cortical structure in Broca's and Wernicke's language areas, as well as frontal brain regions," and, "Preliminary correlations were performed suggesting that frontal gray matter differences may be linked to Spearman's g, which measures successful test performance across multiple cognitive domains (p < 0.05). These genetic brain maps reveal how genes determine individual differences, and may shed light on the heritability of cognitive and linguistic skills, as well as genetic liability for diseases that affect the human cortex."
 
https://www.ncbi.nlm.nih.gov/pubmed/11694885 ; https://sci-hub.tw/10.1038/nn758
 
This further suggests that brain structure, size, and cognitive performance are all heritable and genetic.
 
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3079384/
 
(2011) Joshi et al., study twins to conclude that there is a highly significant genetic contribution to cortical thickness and volume. This is believed to have a significant effect on the neurotubule number and density in individuals and thus a highly significant effect on IQ.
 
In their own words, "The results showed detailed pointwise genetic and environmental contributions on the whole cortex. Several areas in the parietal and frontal lobes were observed to be genetically influenced."
 
The environmental factors are believed to be heavily genetically influenced due to how genetics define interaction and determine developmental reactions in the brain.
 
https://www.ncbi.nlm.nih.gov/pubmed/22713927 ; https://sci-hub.tw/10.1097/WNR.0b013e328355a62a
 
(2012) Yang et al., conclude that there is a, "greater than 80%," genetic contribution to the prefrontal cortex (the part of the brain associated with reward, attention, short-term memory tasks, planning, and motivation.), a significant genetic contribution to the temporal lobe (the part of the brain associated with Visual memory, language comprehension, and emotion association), a significant genetic contribution to the occipital lobe (dubbed the visual processing center of the mammalian brain), and a nearly 80% environmental influence on the parietal lobe (the part of the brain associated with touch, hand-eye coordination, spatial sense, and navigation).
 
https://www.ncbi.nlm.nih.gov/pubmed/22963424 ; https://sci-hub.tw/10.1037/a0029614
 
(2012) Rushton concludes that there has been no narrowing in the mean Black-White IQ difference predicted by heritable g.
 
Rushton also invalidates research by Nisbett, Dickens, and Flynn that show black gains in IQ by evaluating their lack of data and use of specious arguments. He shows that the little data they had to prove these points obscured the topic by invoking alleged age and social class interactions and adoption studies of very young children. Their data was based on ideas, not observations. In his own words on the twin studies cited: "There is no evidence of any special cultural influence, such as extreme deprivation or being raised as a visible minority, that operates in one group and not in others."
 
He shows using a meta-analysis that there has been no reduction in the mean racial differences between Blacks and Whites and that all claims of, "systemic issues," are spurious and unsupported by factual evidence. The credence given to researchers saying that society is to blame for the failures of adopted Blacks comes from a cursory glance at a specious statement - they have no evidence.
 
http://www.sciencedirect.com/science/article/pii/S0160289605000917 ; https://sci-hub.tw/https://www.sciencedirect.com/science/article/abs/pii/S0160289605000917
 
(2006) Templer & Arikawa analyze populations by temperature, skin color, per capita income, and IQ and find stark correlations between all of them.
 
They were able to accurately predict individual IQ by skin color (0,92), mean high Winter temperature of their race (0,76), mean low Winter temperature of their race (0,66), and per capita income (0,63). These findings provide strong support for the idea that colder climates caused selection for higher IQs over an evolutionary epoch.
 
This helps to explain why groups from hotter climates like those found in Africa are less intelligent and thus earn lower incomes.
 
https://www.psychologicalscience.org/index.php/news/releases/babies-prefer-individuals-who-harm-those-that-arent-like-them.html
 
(2013) Karen Wynn shows that infants as young as nine months old prefer individuals who are nice to people of their race and dislike people mean to their race. In addition to this they also like people that are mean to others races and dislike people that are nice to other races.
 
>His centerpiece is a 2002 paper, published in Science by a group led by Stanford geneticist Marcus Feldman, which used a computer program called Structure to cluster populations of the world by their DNA similarities. When they asked the computer to cluster peoples of the world into two groups, the computer gave them EurAfrica and Asia-Oceania-America. When they asked the computer for three groups, the computer gave them Europe, Africa, and Asia-Oceania-America. When they asked the computer for four groups, it gave them Europe, Africa, Asia-Oceania, and America. When they asked it for five groups, it gave them essentially the continents. And when it asked the computer for six, it gave them the continents and the Kalash people of Pakistan. (They asked the computer for up to seventeen clusters, but only published the results up to six.)
 
>A study by Firasat et al. (2006) concluded that the Kalash lack typical Greek Haplogroups such as Haplogroup 21 (E-M35),
>Some of the Kalash people claim to be descendants of Alexander the Great's soldiers; and a recent genetic analysis has substantiated this belief.
>A study by Hellenthal et al. (2014) on the DNA of the Kalash people showed evidence of input from modern day Germany and Austria between 990 and 210 BC, a period that overlaps with that of Alexander the Great...
http://www.well.ox.ac.uk/~gav/admixture/2014-science-final/resources/FAQ.pdf
http://www.cell.com/ajhg/fulltext/S0002-9297(15)00137-8

http://science.sciencemag.org/content/309/5741/1720 ; https://sci-hub.tw/10.1126/science.1116815
 
(2005) Mekel-Bobrov et al., conclude that the gene ASPM is a specific regulator of brain size, and its evolution in the lineage leading to Homo sapiens was driven by strong positive selection. They show that one genetic variant of ASPM in humans arose merely about 5.800 years ago in Eurasia and has since swept to high frequency across Eurasia under strong positivel selection.
 
The gene is almost non-existent in Sub-Saharan Africa.
 
https://www.ucl.ac.uk/tcga/tcgapdf/Thomas-99-intelligence.pdf
 
(1998) Thomas, Miller & Mascie-Taylor conclude that the EST00083 ("expressed sequence tag") is an mtDNA (mitochondrial; maternal) polymorphism found more often in high IQ groups. It is articularly common in Europe (less so in Asia) where it is associated with a lineage that dates back 35.000 years. It is nearly non-existent in Africa.
 
This finding goes along with a discovery by Turner & Partington in 1991 that shows mothers are the primary component in a child's intelligence.
 
https://www.researchgate.net/publication/16004169_Familial_Studies_of_Intelligence_A_Review ; https://sci-hub.tw/10.1126/science.7195071
 
(1981) Bouchard Jr. & McGue analyze 111 studies on familial resemblances in measured intelligence and reveal a profile of average correlations consistent with polygenic inheritance modes.
 
This means that these 111 studies (covering over 1.000.000 people) show evidence of polygenic inheritance modes.
 
Years after this study was performed polygenic inheritance of DNA was confirmed by genetic studies such as (Davies et al., 2011) and (Deary, Johnson & Houlihan, 2009)
 
http://scan.oxfordjournals.org/content/5/2-3/203.full
 
(2009) Way & Lieberman analyze genetic contribution to cultural differences in this piece and draw support for dual-inheritance theory.
 
They show that there are genetic predispositions for IQ, collectivism, individualism, a wide breadth of aspects of socialization, depression, and other psychocultural phenomena which determine the values of societies and their people. They show that populations have mean genetics which means they have mean dispositions and thus mean personalities as well and thus cultures are formed around those same means.
 
These findings are supported by (Simoons, F, 1969; Simoons, F, 1970; Cavalli-Sforza, Menozzi & Piazza, 1994; Holden & Mace, 1997; Durham, 1991; Perry et al., 2007; Campbell, 1965; McElreath & Henrich, 2007; Kroeberm & Kluckhohn, 1952; Sasaki, 2013; Cochran & Harpending, 2009; Bentley, Hahn & Shennan, 2004; Boyd & Richerson, 1985; Gabora, 1995; and so many more)