RESEARCH BASE

Search 3,721 documents across 34 fields — every claim tier-rated by evidence

3,721 Documents 34 Sections 43,625 Citations 34,852 Keywords Indexed 4 Evidence Tiers

3,633 are the core, quality-scored corpus (34 lettered sections — see How We Work); the remaining 88 are cross-corpus synthesis documents (68 InterDocs, 12 Connections, 8 Theories) also indexed here.

1,723 results for "System 2" — page 66 of 87

ZD_2_11 Verified Information & Computation

ZD_2_11 — Reinforcement Learning: Agents, Rewards, and Sequential Decision-Making

Reinforcement learning (RL) is a paradigm of machine learning in which an agent learns to make sequential decisions by interacting with an environment, receiving rewards (or penalties) for its actions, and adjusting its

reinforcement learning MDP Q-learning policy gradient AlphaGo reward
L_1_02 Verified Genetics & Origins

L_1_02 — Interbreeding Events & Genetic Discontinuities

Ancient DNA has established that late human evolution was not a simple replacement story. Expanding populations of Homo sapiens interbred with Neanderthals and Denisovans, and at least one direct first-generation hybrid

interbreeding admixture introgression Neanderthal Denisovan ghost population
L_1_12 Verified Genetics & Origins

L_1_12 — Ghost DNA: Unknown Archaic Hominin Admixture

"Ghost DNA" refers to genetic signals — segments of the genome, deviations in allele frequency distributions, or anomalous phylogenetic patterns — that indicate admixture (interbreeding) between anatomically modern human

ghost DNA archaic admixture unknown hominin introgression ancient DNA aDNA
L_4_02 Verified Genetics & Origins

L_4_02 — Mendel, Inheritance, and the Rediscovery of Genetics

Gregor Johann Mendel (1822–1884), an Augustinian friar at the St. Thomas Abbey in Brno (then part of the Austrian Empire), conducted the foundational experiments in genetics by systematically crossing garden pea plants (

Gregor Mendel Mendelian inheritance law of segregation law of independent assortment dominant recessive
L_4_12 Verified Genetics & Origins

L_4_12 — CRISPR Gene Drives and Population Genetics Ethics

CRISPR gene drives — genetic engineering systems that combine CRISPR-Cas9 gene editing with super-Mendelian inheritance to spread a modified gene through an entire wild population far faster than natural selection — repr

CRISPR Cas9 gene drive population genetics gene editing malaria
L_2_02 Verified Genetics & Origins

L_2_02 — Population Genetics and Hardy-Weinberg Equilibrium

Population genetics — the mathematical study of allele frequency change in populations — provides the quantitative framework underlying evolutionary biology. The Hardy-Weinberg principle (1908), independently derived by

population genetics Hardy-Weinberg equilibrium allele frequency genetic drift natural selection migration
L_2_08 Verified Genetics & Origins

L_2_08 — East Asian Genetics and Population History

East Asia — comprising China, Japan, Korea, Mongolia, Taiwan, and mainland Southeast Asia — is home to the largest human population concentration on Earth and harbors a complex genetic history shaped by major north-south

East Asian genetics Chinese population Japanese genetics Korean genetics Han Chinese Jomon
L_2_11 Verified Genetics & Origins

L_2_11 — Ancient DNA and the Indo-European Question

The Indo-European question — where was the homeland of the Proto-Indo-European (PIE) language, and how did the Indo-European family spread to encompass languages from Ireland to India? — has been one of the most debated

Indo-European Yamnaya steppe Corded Ware ancient DNA language dispersal
L_2_17 Verified Genetics & Origins

L_2_17 — Pacific Islander Genetics: Austronesian Ancestry, Denisovan Introgression, and Oceanian Genomics

Pacific Islander populations — spanning Melanesia, Micronesia, and Polynesia — harbor some of the most genetically complex and scientifically informative genomes in human biology. Their genetic history records multiple d

Pacific Islander genetics Oceanian genomics Denisovan introgression Polynesian motif Austronesian ancestry Melanesian genetics
L_2_16 Verified Genetics & Origins

L_2_16 — Genetic Diversity and Inbreeding: Population Health Across History

Genetic diversity — the total amount of genetic variation within a population — is a fundamental determinant of population health, adaptive potential, and long-term survival. The loss of diversity through inbreeding (mat

genetic diversity inbreeding consanguinity runs of homozygosity ROH inbreeding depression
L_2_12 Verified Genetics & Origins

L_2_12 — Paleogenomics of Africa: The Cradle Revisited

Africa is the cradle of human evolution — the continent where Homo sapiens originated, where the deepest branches of the human family tree diverge, and where the greatest genetic diversity in our species is found. Yet pa

Africa paleogenomics ancient DNA African population structure deep divergence Khoe-San
L_2_07 Verified Genetics & Origins

L_2_07 — European Genetics and Three Ancestral Populations

The genetic history of Europe has been revolutionized by ancient DNA, revealing that most present-day Europeans can be modeled at a broad level as mixtures of three major ancestral components assembled over the past ~10,

European genetics ancient DNA three ancestral populations Western Hunter-Gatherers Early European Farmers Steppe pastoralists
L_2_01 Verified Genetics & Origins

L_2_01 — Domestication Genetics — How Humans Reshaped Life

Domestication — the genetic transformation of wild species into human-dependent organisms — ranks among the most consequential biological processes in Earth's history.

domestication dog origin wheat genetics maize teosinte Belyaev fox experiment domestication syndrome
L_2_10 Verified Genetics & Origins

L_2_10 — Human–Dog Co-Evolution: 40,000 Years Together

The domestication of the dog (Canis lupus familiaris) from gray wolves (Canis lupus) represents the oldest known domestication event and one of the most consequential interspecies relationships in human history — predati

dog domestication wolf Canis lupus familiaris co-evolution Larson Frantz
L_2_00 Genetics & Origins

L_2_00 — Population Regional Genetics: Subfolder Summary

L_2_03 Verified Genetics & Origins

L_2_03 — Ancient African Genetics

Africa harbors the greatest human genetic diversity on Earth — a direct consequence of being the continent of human origin, where populations have accumulated genetic variation for ~300,000+ years. Modern African populat

African genetics ancient African DNA African population history Bantu expansion Khoisan genetics deep population structure
L_2_06 Verified Genetics & Origins

L_2_06 — South Asian Genetics and Population History

South Asia harbors one of the most genetically diverse and internally structured population histories of any world region, reflecting deep settlement, repeated admixture, and long periods of extreme endogamy. The best-su

South Asian genetics Indian subcontinent ANI ASI Ancestral North Indian Ancestral South Indian
L_2_14 Verified Genetics & Origins

L_2_14 — Sex-Biased Admixture: Patrilocal vs. Matrilocal Migration

One of the most powerful revelations from ancient and modern DNA studies is that human migration, conquest, and admixture are almost never sex-neutral — they are systematically biased toward one sex or the other, produci

sex-biased admixture patrilocality matrilocality Y chromosome mtDNA X chromosome
L_2_15 Verified Genetics & Origins

L_2_15 — Population Structure of the Ancient Near East: Farming Spread Genetics

The Neolithic Revolution — the independent invention of agriculture in the Fertile Crescent (~10,000-8,000 BCE) — was one of the most consequential transformations in human history, and ancient DNA has revealed that the

Neolithic farming Near East Fertile Crescent Anatolia Levant
L_2_05 Verified Genetics & Origins

L_2_05 — Americas Peopling Genetics

The peopling of the Americas is one of the clearest cases where ancient DNA and archaeology have converged to overturn an older narrative. The core model now favored by genetics is that the main ancestry of Indigenous Am

Americas peopling Beringia Clovis pre-Clovis Native American genetics mtDNA haplogroups