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.

1,207 results for "Level 4" — page 45 of 61

L_4_14 Verified Genetics & Origins

L_4_14 — Ancient Pathogen Genomics

Ancient pathogen genomics — the recovery, sequencing, and analysis of pathogen DNA from archaeological remains — has revolutionized our understanding of past pandemics, pathogen evolution, and human-disease coevolution.

ancient DNA paleogenomics Yersinia pestis Black Death Justinianic plague ancient tuberculosis
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_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_04 Verified Genetics & Origins

L_2_04 — Oceanian Genetics and Pacific Migration

The human settlement of Oceania represents the last major expansion of Homo sapiens across the globe, and the most remarkable feat of maritime exploration in human history. It occurred in two major phases separated by ~4

Oceanian genetics Pacific migration Lapita Austronesian expansion Polynesia Melanesia
L_3_14 Verified Genetics & Origins

L_3_14 — Genetic Bottleneck Recovery and Founder Effects

A genetic bottleneck occurs when a population's size is drastically reduced, causing a random loss of genetic variation (alleles) that cannot be recovered through subsequent population growth. Founder effects are a speci

genetic-bottleneck founder-effect population-genetics toba-catastrophe effective-population-size heterozygosity
L_3_04 Verified Genetics & Origins

L_3_04 — Y-Chromosome Phylogeny and Patrilineal Deep History

The Y chromosome, transmitted exclusively from father to son, provides a uniquely informative window into patrilineal human history.

Y-chromosome haplogroup patrilineal Y-chromosomal Adam A00 R1b
L_5_04 Verified Genetics & Origins

L_5_04 — Ancient Microbiome and Paleomicrobiology

Paleomicrobiology — the study of ancient microorganisms through the application of molecular techniques (ancient DNA extraction, metagenomics, proteomics) to archaeological and paleontological material — has revolutioniz

microbiome paleomicrobiology ancient DNA aDNA dental calculus coprolite
L_5_14 Verified Genetics & Origins

L_5_14 — Amino Acid Racemization Dating Method

Amino acid racemization (AAR) — a geochronological dating technique based on the chemical conversion of L-amino acids (the biologically predominant enantiomer in living organisms) to D-amino acids (the mirror-image confi

amino acid racemization AAR dating method D/L ratio enantiomers isoleucine epimerization
Y_4_08 Verified Altered States

Y_4_08 — Sleep Science — REM, NREM, and the Ancient Understanding of Sleep

Sleep science has undergone a revolution in the 21st century, fundamentally altering our understanding of why humans sleep. The landmark 2012 discovery of the glymphatic system by Maiken Nedergaard revealed that the brai

sleep REM NREM glymphatic system slow-wave sleep dreams
Y_4_00 Altered States

Y_4_00 — Sleep Trance Perception: Subfolder Summary

Y_4_06 Verified Altered States

Y_4_06 — Synesthesia and Cross-Modal Perception

Synesthesia — the involuntary, consistent experience of one sensory modality triggering perception in another (e.g., hearing colors, tasting shapes) — affects roughly 4% of the general population when broad subtype defin

synesthesia cross-modal perception chromesthesia grapheme-color sound-color mirror-touch
Y_4_02 Verified Altered States

Y_4_02 — Savant Syndrome and Acquired Genius

Savant syndrome — extraordinary ability coexisting with significant cognitive disability — affects roughly 1 in 10 people with autism and ~1 in 2,000 people with other developmental disabilities or brain injuries. What m

savant syndrome acquired savant traumatic brain injury autistic savant Kim Peek Daniel Tammet
Y_4_17 Verified Altered States

Y_4_17 — Sleep Disorders & Parasomnias

Sleep disorders affect an estimated 50–70 million Americans and up to 45% of the global population, encompassing over 80 distinct conditions classified by the International Classification of Sleep Disorders (ICSD-3, 2014

sleep disorders parasomnias narcolepsy sleepwalking REM behavior disorder sleep terrors
Y_4_04 Verified Altered States

Y_4_04 — Entoptic Phenomena and Phosphene Patterns

This document examines Entoptic Phenomena and Phosphene Patterns, a topic within the Consciousness research area. Key areas of investigation include Defining Entoptic Phenomena, Phosphenes: Light from Within, Heinrich Kl

entoptic phenomena phosphene form constants Heinrich Klüver mescaline Lewis-Williams
Y_4_14 Verified Altered States

Y_4_14 — Virtual Reality, Immersive Technology, and Altered Perception

Virtual reality (VR) and immersive technologies create genuine altered states of perception — not merely visual illusions but deep modifications of body ownership, spatial awareness, self-identity, and emotional processi

virtual reality VR augmented reality AR embodiment rubber hand illusion
Y_4_15 Credible Altered States

Y_4_15 — Sensory Overload and Information Flooding: Excess as Altered State

Sensory overload — the state that arises when sensory input exceeds the brain's capacity for orderly processing — represents the mirror image of sensory deprivation as a pathway to altered consciousness. While deprivatio

sensory overload information overload Ganzfeld rave culture overwhelm information flooding
Y_4_12 Verified Altered States

Y_4_12 — Psychosomatic Phenomena and the Placebo Effect

Psychosomatic phenomena — bodily changes produced by mental states — and the placebo effect — measurable physiological improvements following inert treatment — demonstrate that consciousness and belief can directly affec

placebo effect nocebo effect psychosomatic mind-body expectation conditioning
Y_4_16 Verified Altered States

Y_4_16 — Hypnagogia: The Threshold State Between Waking and Sleep

Hypnagogia is the transitional state of consciousness experienced during the onset of sleep (waking-to-sleep), characterized by vivid spontaneous imagery, auditory hallucinations, distorted body perception, and loosened

hypnagogia hypnagogic hypnopompic sleep onset threshold consciousness tetris effect
Y_4_22 Credible Altered States

Y_4_22 — Hypnagogic & Hypnopompic States

Hypnagogia (the transitional state between wakefulness and sleep onset) and hypnopompia (the transition from sleep to waking) are naturally occurring altered states of consciousness experienced universally by humans. Cha

hypnagogia hypnopompia sleep onset phosphenes tetris effect sleep paralysis
Y_4_18 Verified Altered States

Y_4_18 — Sleep Disorders and Parasomnias: Pathologies of Consciousness in Sleep

Sleep disorders affect an estimated 50–70 million Americans and ~1 billion people globally, causing significant morbidity, mortality, and economic burden. The field was transformed by the discovery of distinct sleep stag

sleep-disorders parasomnia insomnia narcolepsy sleep-apnea rem-behavior-disorder