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.
3 results for "Burgess Shale"
R_2_05 — Missing Fossil Record and Punctuated Equilibrium
Darwin himself called the fossil record "the most obvious and gravest objection which can be urged against my theory" — because if evolution occurred through gradual transformation, we should find smooth transitional seq
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
O_5_07 — Anoxic Events and Ocean Dead Zones: Deoxygenation Through Time
Oceanic Anoxic Events (OAEs) were episodes in Earth's history when large portions of the world's oceans became severely depleted of dissolved oxygen (anoxic) or enriched in toxic hydrogen sulfide (euxinic), causing wides
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