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.
28 results for "oxygen" — page 2 of 2
ZB_3_08 — Freshwater Ecology
Freshwater ecosystems — rivers, streams, lakes, ponds, wetlands, and groundwater systems — cover only ~0.8% of Earth's surface and contain ~0.01% of the world's water, yet they support a disproportionate ~6% of all descr
G_4_09 — Bioarchaeology and Forensic Anthropology: Reading the Dead
Bioarchaeology—the study of human remains from archaeological contexts—transforms skeletons from anonymous objects into biographical records of individual lives. Through stable isotope analysis of bone and tooth enamel,
G_1_04 — Isotope Analysis and Provenance Studies
Isotope analysis — the measurement of ratios of stable or radiogenic isotopes preserved in human bone, tooth enamel, animal remains, ceramics, metals, and organic residues — has become one of the most powerful tools in m
G_3_28 — Phlogiston Theory: Productive Fiction and the Birth of Chemistry
Phlogiston theory — developed by German chemist and physician Georg Ernst Stahl in the early 18th century — held that all combustible materials contain a fire-principle called phlogiston (from the Greek phlogistós, "burn
O_5_13 — Paleosols and Ancient Soils: Climate Records in Earth
Paleosols — ancient soils preserved in the geological record — are among the most valuable but often overlooked records of past environmental conditions. When soils are buried by subsequent sedimentation (flooding, volca
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,
R_1_08 — Photosynthesis — The Reaction That Made Complex Life Possible
Photosynthesis — the conversion of light energy into chemical energy — is arguably the most consequential biochemical innovation in Earth's history. Oxygenic photosynthesis, evolved by cyanobacteria approximately 2.4–3.0
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
BROWSE BY SECTION — 3,721 documents across 34 fields