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.

7 results for "placenta"

R_2_13 Verified Biology & Evolution

R_2_13 — Mammalian Radiation: Post-Cretaceous Diversification

The Cretaceous-Paleogene (K-Pg) mass extinction 66 million years ago — triggered by an asteroid impact and possibly exacerbated by Deccan Traps volcanism — eliminated the non-avian dinosaurs and opened vast ecological ni

mammalian radiation adaptive radiation Cretaceous-Paleogene extinction K-Pg boundary placental mammal marsupial
Z_3_05 Verified Molecular Biology

Z_3_05 — Viral Integration and Endogenous Retroviruses

Approximately 8% of the human genome consists of human endogenous retroviruses (HERVs) — the remnants of ancient retroviral infections that integrated into germline cells and were subsequently inherited vertically like a

endogenous retrovirus ERV HERV viral integration retrovirus reverse transcriptase
Z_1_05 Verified Molecular Biology

Z_1_05 — Genomic Imprinting and Parent-of-Origin Effects

Genomic imprinting is an epigenetic phenomenon in which a gene's expression depends on whether it was inherited from the mother or the father — violating the standard Mendelian assumption that both parental copies functi

genomic imprinting parent-of-origin effect epigenetics DNA methylation imprinting control region ICR
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_17 Verified Genetics & Origins

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

endogenous retroviruses HERVs HERV-K HERV-W syncytin retroviral integration
R_3_02 Verified Biology & Evolution

R_3_02 — Horizontal Gene Transfer in Complex Life

For decades, the "tree of life" was the central metaphor of evolutionary biology — species branching neatly from common ancestors through vertical gene transmission (parent to offspring). This metaphor is now BROKEN, at

horizontal gene transfer HGT lateral gene transfer LGT endosymbiosis mitochondria
R_1_07 Verified Biology & Evolution

R_1_07 — Viruses as Evolutionary Drivers — Endogenous Retroviruses and Genomic Integration

Viruses are not merely disease agents — they are fundamental architects of evolution. The human genome contains approximately ~8% endogenous retroviral (ERV) sequences (~100,000 ERV fragments), meaning roughly eight time

virus retrovirus endogenous retrovirus ERV HERV viral DNA