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.

1,984 results for "Tic Tac" — page 37 of 100

L_1_04 Verified Genetics & Origins

L_1_04 — Archaic Human Species Synthesis

The human evolutionary tree is far more complex than the older linear model suggested. Fossils, ancient DNA, and proteomics now show that Homo sapiens overlapped with several other hominin lineages, including Neanderthal

archaic humans Neanderthal Denisovan Homo floresiensis hobbit Homo luzonensis
L_1_09 Verified Genetics & Origins

L_1_09 — Ghost Populations & Missing Archaic Lineages

Ghost populations are human groups whose existence is inferred from statistical signatures in modern or ancient genomes rather than from direct fossil or archaeological evidence. The term reflects a central challenge of

ghost population archaic introgression missing lineage unsampled population West African introgression superarchaic
L_1_03 Verified Genetics & Origins

L_1_03 — Mitochondrial Eve, Y-Chromosomal Adam & Population Origins

Mitochondrial Eve and Y-chromosomal Adam are the most recent common ancestors of all living humans along strictly maternal and strictly paternal lines. They were not the first woman and man, were not a couple, and do not

mitochondrial Eve Y-chromosomal Adam mtDNA haplogroup Out of Africa Jebel Irhoud
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_13 Verified Genetics & Origins

L_4_13 — Ancient DNA: Methods, Revelations, and Ethical Debates

Ancient DNA (aDNA) — genetic material recovered from biological remains thousands to hundreds of thousands of years old — has revolutionized our understanding of human evolution, migration, and population history. The fi

ancient DNA aDNA paleogenomics PCR next-generation sequencing Svante Pääbo
L_4_07 Verified Genetics & Origins

L_4_07 — Twin Studies and Heritability

Twin studies represent one of the most powerful natural experiments in human genetics, exploiting the fact that monozygotic (MZ, "identical") twins share ~100% of their DNA while dizygotic (DZ, "fraternal") twins share ~

twin study monozygotic dizygotic heritability concordance ACE model
L_4_05 Verified Genetics & Origins

L_4_05 — Paleogenomics Methods and Ancient DNA

Paleogenomics — the study of ancient genomes — has transformed archaeology, anthropology, and evolutionary biology over the past two decades, recognized by the 2022 Nobel Prize in Physiology or Medicine awarded to Svante

paleogenomics ancient DNA aDNA ancient DNA extraction petrous bone DNA degradation
L_4_15 Verified Genetics & Origins

L_4_15 — Y-Chromosome and mtDNA Mismatch Patterns in Human Populations

The Y chromosome (paternally inherited, non-recombining) and mitochondrial DNA (maternally inherited) provide independent genealogical records of male and female lineage histories, respectively. When these two markers te

y-chromosome mitochondrial-dna sex-biased-migration patrilocality matrilocality haplogroup
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_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_18 Verified Genetics & Origins

L_2_18 — Archaic Admixture in Africa (Ghost Populations)

While Neanderthal and Denisovan admixture in non-African populations has been well-documented since Svante Pääbo's landmark 2010 Neanderthal genome paper, evidence for archaic admixture within Africa represents a more re

archaic admixture ghost population African genetics ancient DNA introgression archaic hominin
L_3_16 Verified Genetics & Origins

L_3_16 — Genomic Imprinting & Evolutionary Conflict

Genomic imprinting — the epigenetic phenomenon in which a subset of genes (~100–200 in mammals) are expressed from only one parental allele, with the other allele silenced by DNA methylation and histone modification esta

genomic imprinting parent-of-origin expression epigenetics kinship theory parental conflict IGF2
L_3_18 Verified Genetics & Origins

L_3_18 — Horizontal Gene Transfer in Eukaryotes

Horizontal gene transfer (HGT) — the movement of genetic material between organisms through mechanisms other than vertical parent-to-offspring inheritance — was long considered a predominantly prokaryotic phenomenon, cen

horizontal gene transfer lateral gene transfer HGT LGT eukaryotes introgression
L_5_03 Verified Genetics & Origins

L_5_03 — Pharmacogenomics and Ancestral Medicine

Pharmacogenomics — the study of how genetic variation influences individual responses to drugs — bridges genetics, pharmacology, and clinical medicine. Humans carry extensive polymorphism in genes encoding drug-metaboliz

pharmacogenomics CYP2D6 CYP2C_5_04 drug metabolism personalized medicine warfarin
L_5_01 Verified Genetics & Origins

L_5_01 — Human Microbiome and Co-Evolution

The human microbiome — the aggregate community of microorganisms (bacteria, archaea, fungi, viruses, protists) living on and within the human body — comprises roughly 38 trillion microbial cells (Sender et al., 2016, Cel

microbiome gut bacteria metagenomics holobiont dysbiosis Firmicutes
L_5_12 Credible Genetics & Origins

L_5_12 — Microbiome-Consciousness Connection: Gut-Brain Axis and Microbial Influence on Mind

The microbiome-gut-brain axis — the bidirectional communication network linking the ~38 trillion microorganisms inhabiting the human gastrointestinal tract with the central nervous system — has emerged as one of the most

microbiome gut-brain axis psychobiotics vagus nerve serotonin Cryan
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_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_01 Verified Altered States

Y_4_01 — Lucid Dreaming Research

Lucid dreaming — being consciously aware that you are dreaming WHILE dreaming, and potentially controlling dream content — was scientifically verified in 1975-1981 through a breakthrough protocol: pre-arranged EYE SIGNAL

lucid dreaming dream consciousness REM sleep sleeping brain metacognition prefrontal cortex