RESEARCH BASE
Search 3,721 documents across 34 fields — every claim tier-rated by evidence
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.
675 results for "SSI" — page 23 of 34
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
L_1_01 — Ancient DNA & Population Genetics
Modern paleogenomics has shown that human evolution was shaped by interbreeding, population structure, and repeated demographic turnover rather than a simple single-line progression. Ancient DNA revealed previously unkno
L_1_10 — Neanderthal Genome and Legacy in Modern Humans
The sequencing of the Neanderthal genome ranks among the most significant achievements in modern biology. Beginning with the draft genome of Green et al. (2010) and refined by later high-coverage genomes from the Altai,
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
L_1_18 — Human Migration: Out of Africa, Dispersal Patterns, and the Peopling of the World
The migration of Homo sapiens out of Africa and across the globe is one of the most extensively studied processes in human evolutionary history, now reconstructed through converging evidence from genetics (mitochondrial
L_1_08 — Denisovans — Archaic Hominin Deep Dive
Denisovans are an extinct group of archaic hominins identified primarily through ancient DNA analysis rather than traditional fossil morphology — making them history's first hominins to be discovered by genetics. In 2010
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
L_1_16 — Denisovan Genetics and Legacy
The Denisovans — an extinct group of archaic humans first identified in 2010 from ancient DNA extracted from a finger bone fragment found in Denisova Cave, Altai Mountains, Siberia (~41,000 years old) — represent one of
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 (
L_4_10 — Sex Chromosome Evolution
Sex chromosomes — the genetic elements that determine biological sex in many organisms — represent one of the most remarkable stories in genome evolution. In mammals, the XX/XY system prevails: females have two X chromos
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
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
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
L_3_06 — Genetics of Intelligence and Cognition
The genetics of intelligence — one of the most studied yet contentious areas in behavioral genetics — has established that cognitive ability, as measured by standardized tests, has a substantial heritable component (~50–
L_3_17 — Endogenous Retroviruses (HERVs) in the Human Genome
Human endogenous retroviruses (HERVs) — remnants of ancient retroviral infections that integrated into the germline DNA of human ancestors and have been vertically transmitted through the host genome for millions of year
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
L_3_07 — Behavioral Genetics: Nature and Nurture
Behavioral genetics — the scientific study of how genetic and environmental factors contribute to individual differences in behavior — has transformed our understanding of human psychology over the past half-century. Thr
L_5_11 — Genetics of Altitude Adaptation: Tibet, Andes, Ethiopia
High-altitude adaptation represents one of the most dramatic and best-studied examples of natural selection in contemporary human populations. More than 140 million people worldwide live at elevations above 2,500 meters,
Y_4_20 — Drumming & Trance Neuroscience
Shamanic drumming — typically monotonous percussive rhythms at approximately 4–4.5 beats per second — has been used across virtually every indigenous culture as a primary technology for inducing trance states, and modern
Y_4_11 — Trance States Across Cultures
Trance — an altered state of consciousness characterized by narrowed or shifted attention, altered sense of self, reduced awareness of external surroundings, and modified responsiveness — is one of the most universal fea
BROWSE BY SECTION — 3,721 documents across 34 fields