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.
149 results for "1421 hypothesis" — page 6 of 8
R_5_02 — Megafauna Extinction: Quaternary Losses and the Overkill Debate
Between ~50,000 and 10,000 years ago, Earth lost the majority of its large-bodied animals (megafauna >44 kg) — woolly mammoths, ground sloths, saber-toothed cats, giant wombats, moa, and dozens of other spectacular speci
R_2_01 — Human Brain Evolution and the Cognitive Revolution
The human brain tripled in size over 3 million years — from ~400 cm³ (Australopithecus) to ~1,400 cm³ (modern Homo sapiens). This is the most dramatic encephalization in the history of life, and NO consensus exists on wh
R_2_08 — Bipedalism — Why We Walk Upright and What It Cost Us
Bipedalism — habitual upright walking on two legs — is the defining characteristic of the hominin lineage, predating brain enlargement, tool use, and language by millions of years. The earliest evidence comes from Sahela
R_1_02 — The Cambrian Explosion
Between ~541 and ~520 million years ago, nearly ALL major animal body plans (phyla) appeared in the fossil record in an evolutionary "instant" — roughly 20 million years. Before this, life had been single-celled for ~3 b
R_1_18 — Mass Extinction Periodicity
The question of whether mass extinctions follow a periodic pattern — recurring at regular intervals driven by astronomical or geological cycles — has been one of the most provocative and contentious hypotheses in paleont
S_4_05 — Asteroid Deflection and Planetary Defense
Asteroid and comet impacts represent the only existential risk with a proven extinction track record — the Chicxulub impact 66 million years ago ended the Cretaceous and eliminated ~75% of species including non-avian din
S_4_06 — Interstellar Communication — SETI, Breakthrough Listen, and the Search for Intelligence
The scientific search for extraterrestrial intelligence (SETI) has proceeded for over six decades since Frank Drake's Project Ozma (1960) first aimed a radio telescope at nearby stars, yet no confirmed signal of intellig
S_5_13 — Prediction Markets: Collective Intelligence and Crowd Forecasting
Prediction markets — markets where participants buy and sell contracts whose payoffs depend on the outcome of future events — aggregate dispersed information into probability estimates with remarkable accuracy, often out
S_2_02 — Post-Human Futures and Digital Consciousness
What comes AFTER humanity? Post-human futures represent the landscape of possibilities once technology transforms the human condition beyond recognition. This spans physical pathways (space colonization, life extension,
F_1_11 — Sweet Potato Paradox — Pre-Columbian Trans-Pacific Contact Evidence
The sweet potato paradox — the presence of Ipomoea batatas (a plant of unambiguous South American origin) across Polynesia in pre-Columbian contexts — is the single most widely accepted piece of evidence for trans-Pacifi
F_1_07 — First Americans Debate — Clovis, Pre-Clovis, and Coastal Routes
The question of when and how humans first reached the Americas has been transformed in the 21st century by a series of discoveries that have demolished the long-reigning "Clovis-first" paradigm. For decades, the archaeol
F_1_10 — Kennewick Man and the Pre-Clovis Debate
The question of when and how humans first reached the Americas has been one of archaeology's most contentious debates for over a century. For decades, the Clovis First model dominated: the earliest Americans were big-gam
F_4_06 — Pre-Indo-European Substrate Cultures of Europe
This document examines Pre-Indo-European Substrate Cultures of Europe, a topic within the Lost Connections research area. Key areas of investigation include Europe Before the Steppe Migrations, The Indo-European Expansio
F_3_01 — The Agricultural Revolution
The Agricultural Revolution (~10,000 BCE) — the transition from hunting-gathering to farming — is arguably the most consequential event in human history. It enabled cities, writing, religion, states, armies, and eventual
ZA_2_01 — Time: Physics and Philosophy
Time is arguably the deepest unsolved problem in physics and philosophy. Physics reveals: (1) time is relative, not absolute — Einstein showed it flows at different rates depending on velocity and gravity; (2) the fundam
ZA_4_07 — Boltzmann Brains and Statistical Mechanics Paradoxes
The Boltzmann brain paradox reveals a deep tension between statistical mechanics and cosmology. Ludwig Boltzmann (1896) suggested that the low entropy of the observable universe might be a rare thermal fluctuation from e
ZA_3_06 — Grand Unified Theories: Merging the Forces
Grand Unified Theories (GUTs) attempt to merge the three non-gravitational forces — strong, weak, and electromagnetic — into a single gauge interaction at extremely high energies (~10¹⁶ GeV). Motivated by the approximate
I_1_08 — The Drake Equation, Fermi Paradox, and UAP Implications
The Drake Equation and the Fermi Paradox represent the two foundational frameworks for thinking about the probability of extraterrestrial intelligence — and their intersection with UAP discourse is both natural and conte
I_1_01 — The UAP Phenomenon: Overview and Historical Context
Unidentified Aerial Phenomena (UAP) — formerly "UFOs" — represent one of the most persistent and globally reported anomalous phenomena in modern history. Reports of unexplained aerial objects span from antiquity (Roman p
I_5_09 — Cattle Mutilation and UAP Association
Cattle mutilation refers to the unexplained deaths of livestock — predominantly cattle — found with specific organs or tissue removed with what witnesses describe as "surgical precision," often accompanied by complete or
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