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{{html}}<hr style="border: 3px solid red;">{{/html}} |
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+{{expand title="Study: A Review of Intelligence GWAS Hits: Their Relationship to Country IQ and the Issue of Spatial Autocorrelation" expanded="false"}} |
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+**Source:** *Intelligence (Elsevier)* |
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+**Date of Publication:** *2015* |
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+**Author(s):** *Davide Piffer* |
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+**Title:** *"A Review of Intelligence GWAS Hits: Their Relationship to Country IQ and the Issue of Spatial Autocorrelation"* |
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+**DOI:** [10.1016/j.intell.2015.08.008](https://doi.org/10.1016/j.intell.2015.08.008) |
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+**Subject Matter:** *Genetics, Intelligence, GWAS, Population Differences* |
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+--- |
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+ |
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+## **Key Statistics** |
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+1. **General Observations:** |
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+ - Study analyzed **genome-wide association studies (GWAS) hits** linked to intelligence. |
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+ - Found a **strong correlation (r = .91) between polygenic intelligence scores and national IQ levels**. |
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+ |
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+2. **Subgroup Analysis:** |
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+ - Factor analysis of **9 intelligence-associated alleles** revealed a metagene correlated with **country IQ (r = .86)**. |
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+ - **Allele frequencies varied significantly by continent**, aligning with observed population differences in cognitive ability. |
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+ |
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+3. **Other Significant Data Points:** |
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+ - GWAS intelligence SNPs predicted **IQ levels more strongly than random genetic markers**. |
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+ - Genetic differentiation (Fst values) showed that **selection pressure, rather than drift, influenced intelligence-related allele distributions**. |
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+ |
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+--- |
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+ |
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+## **Findings** |
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+1. **Primary Observations:** |
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+ - Intelligence-associated SNP frequencies correlate **highly with national IQ levels**. |
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+ - Genetic selection for intelligence appears **stronger than selection for height-related genes**. |
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+ |
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+2. **Subgroup Trends:** |
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+ - **East Asian populations** exhibited the **highest frequencies of intelligence-associated alleles**. |
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+ - **African populations** showed lower frequencies compared to European and East Asian populations. |
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+ |
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+3. **Specific Case Analysis:** |
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+ - Polygenic scores using **intelligence-related alleles significantly outperformed random SNPs** in predicting IQ. |
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+ - Selection pressures **may explain differences in global intelligence distribution** beyond genetic drift effects. |
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+ |
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+--- |
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+ |
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+## **Critique and Observations** |
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+1. **Strengths of the Study:** |
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+ - **Comprehensive genetic analysis** of intelligence-linked SNPs. |
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+ - Uses **multiple statistical methods (factor analysis, Fst analysis) to confirm results**. |
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+ |
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+2. **Limitations of the Study:** |
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+ - **Correlation does not imply causation**; factors beyond genetics influence intelligence. |
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+ - **Limited number of GWAS-identified intelligence alleles**—future studies may identify more. |
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+ |
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+3. **Suggestions for Improvement:** |
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+ - Larger **cross-population GWAS studies** needed to validate findings. |
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+ - Investigate **non-genetic contributors to IQ variance** in addition to genetic factors. |
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+ |
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+--- |
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+ |
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+## **Relevance to Subproject** |
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+- Supports research on **genetic influences on intelligence at a population level**. |
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+- Aligns with broader discussions on **cognitive genetics and natural selection effects**. |
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+- Provides a **quantitative framework for analyzing polygenic selection in intelligence studies**. |
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+ |
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+--- |
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+ |
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+## **Suggestions for Further Exploration** |
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+1. Conduct **expanded GWAS studies** including diverse populations. |
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+2. Investigate **gene-environment interactions influencing intelligence**. |
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+3. Explore **historical selection pressures shaping intelligence-related alleles**. |
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+ |
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+--- |
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+ |
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+## **Summary of Research Study** |
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+This study reviews **genome-wide association study (GWAS) findings on intelligence**, demonstrating a **strong correlation between polygenic intelligence scores and national IQ levels**. The research highlights how **genetic selection may explain population-level cognitive differences beyond genetic drift effects**. Intelligence-linked alleles showed **higher variability across populations than height-related alleles**, suggesting stronger selection pressures. |
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+ |
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+This summary provides an accessible, at-a-glance overview of the study’s contributions. Please refer to the full paper for in-depth analysis. |
|
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+ |
|
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+--- |
|
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+ |
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+## **📄 Download Full Study** |
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+[[Download Full Study>>attach:10.1016_j.intell.2015.08.008.pdf]] |
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+ |
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+{{/expand}} |
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+ |
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+{{html}}<hr style="border: 3px solid red;">{{/html}} |
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+ |
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+{{expand title="Study: Survey of Expert Opinion on Intelligence: Intelligence Research, Experts' Background, Controversial Issues, and the Media" expanded="false"}} |
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+**Source:** *Intelligence (Elsevier)* |
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+**Date of Publication:** *2019* |
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+**Author(s):** *Heiner Rindermann, David Becker, Thomas R. Coyle* |
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+**Title:** *"Survey of Expert Opinion on Intelligence: Intelligence Research, Experts' Background, Controversial Issues, and the Media"* |
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+**DOI:** [10.1016/j.intell.2019.101406](https://doi.org/10.1016/j.intell.2019.101406) |
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+**Subject Matter:** *Psychology, Intelligence Research, Expert Analysis* |
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+ |
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+--- |
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+ |
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+## **Key Statistics** |
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+1. **General Observations:** |
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+ - Survey of **102 experts** on intelligence research and public discourse. |
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+ - Evaluated experts' backgrounds, political affiliations, and views on controversial topics in intelligence research. |
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+ |
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+2. **Subgroup Analysis:** |
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+ - **90% of experts were from Western countries**, and **83% were male**. |
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+ - Political spectrum ranged from **54% left-liberal, 24% conservative**, with significant ideological influences on views. |
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+ |
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+3. **Other Significant Data Points:** |
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+ - Experts rated media coverage of intelligence research as **poor (avg. 3.1 on a 9-point scale)**. |
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+ - **50% of experts attributed US Black-White IQ differences to genetic factors, 50% to environmental factors**. |
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+ |
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+--- |
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+ |
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+## **Findings** |
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+1. **Primary Observations:** |
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+ - Experts overwhelmingly support **the g-factor theory of intelligence**. |
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+ - **Heritability of intelligence** was widely accepted, though views differed on race and group differences. |
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+ |
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+2. **Subgroup Trends:** |
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+ - **Left-leaning experts were more likely to reject genetic explanations for group IQ differences**. |
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+ - **Right-leaning experts tended to favor a stronger role for genetic factors** in intelligence disparities. |
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+ |
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+3. **Specific Case Analysis:** |
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+ - The study compared **media coverage of intelligence research** with expert opinions. |
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+ - Found a **disconnect between journalists and intelligence researchers**, especially regarding politically sensitive issues. |
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+ |
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+--- |
|
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+ |
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+## **Critique and Observations** |
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+1. **Strengths of the Study:** |
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+ - **Largest expert survey on intelligence research** to date. |
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+ - Provides insight into **how political orientation influences scientific perspectives**. |
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+ |
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+2. **Limitations of the Study:** |
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+ - **Sample primarily from Western countries**, limiting global perspectives. |
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+ - Self-selection bias may skew responses toward **those more willing to engage with controversial topics**. |
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+ |
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+3. **Suggestions for Improvement:** |
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+ - Future studies should include **a broader range of global experts**. |
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+ - Additional research needed on **media biases and misrepresentation of intelligence research**. |
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+ |
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+--- |
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+ |
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+## **Relevance to Subproject** |
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+- Provides insight into **expert consensus and division on intelligence research**. |
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+- Highlights the **role of media bias** in shaping public perception of intelligence science. |
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+- Useful for understanding **the intersection of science, politics, and public discourse** on intelligence research. |
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+ |
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+--- |
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+ |
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+## **Suggestions for Further Exploration** |
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+1. Examine **cross-national differences** in expert opinions on intelligence. |
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+2. Investigate how **media bias impacts public understanding of intelligence research**. |
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+3. Conduct follow-up studies with **a more diverse expert pool** to test findings. |
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+ |
|
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+--- |
|
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+ |
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+## **Summary of Research Study** |
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+This study surveys **expert opinions on intelligence research**, analyzing **how backgrounds, political ideologies, and media representation influence perspectives on intelligence**. The findings highlight **divisions in scientific consensus**, particularly on **genetic vs. environmental causes of IQ disparities**. Additionally, the research uncovers **widespread dissatisfaction with media portrayals of intelligence research**, pointing to **the impact of ideological biases on public discourse**. |
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+ |
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+This summary provides an accessible, at-a-glance overview of the study’s contributions. Please refer to the full paper for in-depth analysis. |
|
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+ |
|
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+--- |
|
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+ |
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+## **📄 Download Full Study** |
|
618 |
+[[Download Full Study>>attach:10.1016_j.intell.2019.101406.pdf]] |
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+ |
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+{{/expand}} |
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+ |
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+{{html}}<hr style="border: 3px solid red;">{{/html}} |
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+ |
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+{{expand title="Study: Is Homo sapiens polytypic? Human taxonomic diversity and its implications" expanded="false"}} |
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+**Source:** *Medical Hypotheses (Elsevier)* |
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+**Date of Publication:** *2010* |
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+**Author(s):** *Michael A. Woodley* |
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+**Title:** *"Is Homo sapiens polytypic? Human taxonomic diversity and its implications"* |
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+**DOI:** [10.1016/j.mehy.2009.07.046](https://doi.org/10.1016/j.mehy.2009.07.046) |
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+**Subject Matter:** *Human Taxonomy, Evolutionary Biology, Anthropology* |
|
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+ |
|
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+--- |
|
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+ |
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+## **Key Statistics** |
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+1. **General Observations:** |
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+ - The study argues that **Homo sapiens is polytypic**, meaning it consists of multiple subspecies rather than a single monotypic species. |
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+ - Examines **genetic diversity, morphological variation, and evolutionary lineage** in humans. |
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+ |
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+2. **Subgroup Analysis:** |
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+ - Discusses **four primary definitions of race/subspecies**: Essentialist, Taxonomic, Population-based, and Lineage-based. |
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+ - Suggests that **human heterozygosity levels are comparable to species that are classified as polytypic**. |
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+ |
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+3. **Other Significant Data Points:** |
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+ - The study evaluates **FST values (genetic differentiation measure)** and argues that human genetic differentiation is comparable to that of recognized subspecies in other species. |
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+ - Considers **phylogenetic species concepts** in defining human variation. |
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+ |
|
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+--- |
|
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+ |
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+## **Findings** |
|
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+1. **Primary Observations:** |
|
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+ - Proposes that **modern human populations meet biological criteria for subspecies classification**. |
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+ - Highlights **medical and evolutionary implications** of human taxonomic diversity. |
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+ |
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+2. **Subgroup Trends:** |
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+ - Discusses **how race concepts evolved over time** in biological sciences. |
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+ - Compares **human diversity with that of other primates** such as chimpanzees and gorillas. |
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+ |
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+3. **Specific Case Analysis:** |
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+ - Evaluates how **genetic markers correlate with population structure**. |
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+ - Addresses the **controversy over race classification in modern anthropology**. |
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+ |
|
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+--- |
|
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+ |
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+## **Critique and Observations** |
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+1. **Strengths of the Study:** |
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+ - Uses **comparative species analysis** to assess human classification. |
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+ - Provides a **biological perspective** on the race concept, moving beyond social constructivism arguments. |
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+ |
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+2. **Limitations of the Study:** |
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+ - Controversial topic with **strong opposing views in anthropology and genetics**. |
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+ - **Relies on broad genetic trends**, but does not analyze individual-level genetic variation in depth. |
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+ |
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+3. **Suggestions for Improvement:** |
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+ - Further research should **incorporate whole-genome studies** to refine subspecies classifications. |
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+ - Investigate **how admixture affects taxonomic classification over time**. |
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+ |
|
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+--- |
|
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+ |
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+## **Relevance to Subproject** |
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+- Contributes to discussions on **evolutionary taxonomy and species classification**. |
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+- Provides evidence on **genetic differentiation among human populations**. |
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+- Highlights **historical and contemporary scientific debates on race and human variation**. |
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+ |
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+--- |
|
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+ |
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+## **Suggestions for Further Exploration** |
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+1. Examine **FST values in modern and ancient human populations**. |
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+2. Investigate how **adaptive evolution influences population differentiation**. |
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+3. Explore **the impact of genetic diversity on medical treatments and disease susceptibility**. |
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+ |
|
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+--- |
|
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+ |
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+## **Summary of Research Study** |
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+This study evaluates **whether Homo sapiens should be classified as a polytypic species**, analyzing **genetic diversity, evolutionary lineage, and morphological variation**. Using comparative analysis with other primates and mammals, the research suggests that **human populations meet biological criteria for subspecies classification**, with implications for **evolutionary biology, anthropology, and medicine**. |
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+ |
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+This summary provides an accessible, at-a-glance overview of the study’s contributions. Please refer to the full paper for in-depth analysis. |
|
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+ |
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+--- |
|
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+ |
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+## **📄 Download Full Study** |
|
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+[[Download Full Study>>attach:10.1016_j.mehy.2009.07.046.pdf]] |
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+ |
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+{{/expand}} |
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+ |
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+{{html}}<hr style="border: 3px solid red;">{{/html}} |
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+ |
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+{{expand title="Study: The Wilson Effect: The Increase in Heritability of IQ With Age" expanded="false"}} |
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+**Source:** *Twin Research and Human Genetics (Cambridge University Press)* |
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+**Date of Publication:** *2013* |
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+**Author(s):** *Thomas J. Bouchard Jr.* |
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+**Title:** *"The Wilson Effect: The Increase in Heritability of IQ With Age"* |
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+**DOI:** [10.1017/thg.2013.54](https://doi.org/10.1017/thg.2013.54) |
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+**Subject Matter:** *Intelligence, Heritability, Developmental Psychology* |
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+ |
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+--- |
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+ |
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+## **Key Statistics** |
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+1. **General Observations:** |
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+ - The study documents how the **heritability of IQ increases with age**, reaching an asymptote at **0.80 by adulthood**. |
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+ - Analysis is based on **longitudinal twin and adoption studies**. |
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+ |
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+2. **Subgroup Analysis:** |
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+ - Shared environmental influence on IQ **declines with age**, reaching **0.10 in adulthood**. |
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+ - Monozygotic twins show **increasing genetic similarity in IQ over time**, while dizygotic twins become **less concordant**. |
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+ |
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+3. **Other Significant Data Points:** |
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+ - Data from the **Louisville Longitudinal Twin Study and cross-national twin samples** support findings. |
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+ - IQ stability over time is **influenced more by genetics than by shared environmental factors**. |
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+ |
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+--- |
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+ |
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+## **Findings** |
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+1. **Primary Observations:** |
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+ - Intelligence heritability **strengthens throughout development**, contrary to early environmental models. |
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+ - Shared environmental effects **decrease by late adolescence**, emphasizing **genetic influence in adulthood**. |
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+ |
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+2. **Subgroup Trends:** |
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+ - Studies from **Scotland, Netherlands, and the US** show **consistent patterns of increasing heritability with age**. |
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+ - Findings hold across **varied socio-economic and educational backgrounds**. |
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+ |
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+3. **Specific Case Analysis:** |
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+ - Longitudinal adoption studies show **declining impact of adoptive parental influence on IQ** as children age. |
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+ - Cross-sectional twin data confirm **higher IQ correlations for monozygotic twins in adulthood**. |
|
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+ |
|
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+--- |
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+ |
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+## **Critique and Observations** |
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+1. **Strengths of the Study:** |
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+ - **Robust dataset covering multiple twin and adoption studies over decades**. |
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+ - **Clear, replicable trend** demonstrating the increasing role of genetics in intelligence. |
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+ |
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+2. **Limitations of the Study:** |
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+ - Findings apply primarily to **Western industrialized nations**, limiting generalizability. |
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+ - **Lack of neurobiological mechanisms** explaining how genes express their influence over time. |
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+ |
|
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+3. **Suggestions for Improvement:** |
|
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+ - Future research should investigate **gene-environment interactions in cognitive aging**. |
|
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+ - Examine **heritability trends in non-Western populations** to determine cross-cultural consistency. |
|
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+ |
|
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+--- |
|
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+ |
|
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+## **Relevance to Subproject** |
|
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+- Provides **strong evidence for the genetic basis of intelligence**. |
|
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+- Highlights the **diminishing role of shared environment in cognitive development**. |
|
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+- Supports research on **cognitive aging and heritability across the lifespan**. |
|
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+ |
|
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+--- |
|
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+ |
|
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+## **Suggestions for Further Exploration** |
|
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+1. Investigate **neurogenetic pathways underlying IQ development**. |
|
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+2. Examine **how education and socioeconomic factors interact with genetic IQ influences**. |
|
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+3. Study **heritability trends in aging populations and cognitive decline**. |
|
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+ |
|
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+--- |
|
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+ |
|
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+## **Summary of Research Study** |
|
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+This study documents **The Wilson Effect**, demonstrating how the **heritability of IQ increases throughout development**, reaching a plateau of **0.80 by adulthood**. The findings indicate that **shared environmental effects diminish with age**, while **genetic influences on intelligence strengthen**. Using **longitudinal twin and adoption data**, the research provides **strong empirical support for the increasing role of genetics in cognitive ability over time**. |
|
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+ |
|
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+This summary provides an accessible, at-a-glance overview of the study’s contributions. Please refer to the full paper for in-depth analysis. |
|
780 |
+ |
|
781 |
+--- |
|
782 |
+ |
|
783 |
+## **📄 Download Full Study** |
|
784 |
+[[Download Full Study>>attach:10.1017_thg.2013.54.pdf]] |
|
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+ |
|
786 |
+{{/expand}} |
|
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+ |
|
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+{{html}}<hr style="border: 3px solid red;">{{/html}} |