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.

2,598 results for "Philip K Dick" — page 111 of 130

R_4_01 Verified Biology & Evolution

R_4_01 — The Evolution of Flight: Birds, Bats, Insects, and Pterosaurs

Powered flight has evolved independently at least four times in the history of life — in insects (~350–400 Ma), pterosaurs (~230 Ma), birds (~160 Ma), and bats (~55 Ma) — making it one of evolution's most spectacular exa

flight evolution powered flight feathered dinosaurs Archaeopteryx avian evolution insect wings
R_4_05 Verified Biology & Evolution

R_4_05 — Seed Plants and Angiosperm Evolution

Angiosperms (flowering plants) are the most species-rich and ecologically dominant group of land plants, comprising roughly 300,000–400,000 species — over 90% of all living plant species. Their origin and rapid diversifi

seed plants spermatophytes angiosperms flowering plants gymnosperm Cretaceous terrestrial revolution
R_4_10 Verified Biology & Evolution

R_4_10 — Cetacean Evolution: Whales, Dolphins, and the Return to the Sea

The evolution of cetaceans — whales, dolphins, and porpoises — from small, four-legged terrestrial mammals to the largest animals ever to live on Earth is one of the best-documented major evolutionary transitions, suppor

cetacean whale evolution dolphin Ambulocetus Pakicetus Basilosaurus
R_4_07 Verified Biology & Evolution

R_4_07 — Venom Evolution and Biochemical Arms Races

Venom — a cocktail of bioactive molecules injected via a specialized delivery apparatus (fangs, stingers, harpoons, nematocysts, spurs) to subdue prey, deter predators, or aid in competition — has evolved independently o

venom toxin snake venom spider venom cone snail conotoxin
R_4_12 Verified Biology & Evolution

R_4_12 — Mimicry: Batesian, Müllerian, and Aggressive Deception

Mimicry — the resemblance of one organism (the mimic) to another (the model) or to an environmental feature, evolved to deceive a third party (the signal receiver, typically a predator) — is one of the most elegant demon

mimicry Batesian mimicry Müllerian mimicry aggressive mimicry aposematism warning coloration
R_4_15 Verified Biology & Evolution

R_4_15 — Insect Evolution: Flight, Metamorphosis, and Mega-Diversity

Insects (class Insecta) are the most species-rich group of organisms on Earth — with over 1 million described species and an estimated 5–10 million total, they account for approximately 80% of all known animal species. T

insect insect evolution flight wing pterygota metamorphosis
R_4_09 Verified Biology & Evolution

R_4_09 — Parasitism and Host-Parasite Coevolution

Parasitism — a symbiotic relationship in which one organism (the parasite) benefits at the expense of another (the host) — is arguably the most common lifestyle on Earth. By some estimates, over 40% of all described spec

parasitism host-parasite coevolution Red Queen arms race Plasmodium malaria
R_3_08 Verified Biology & Evolution

R_3_08 — Speciation Mechanisms and Reproductive Isolation

Speciation — the process by which one species splits into two or more reproductively isolated lineages — is the engine of biodiversity. Ernst Mayr's biological species concept (1942) defines species as groups of interbre

speciation reproductive isolation allopatric speciation sympatric speciation peripatric speciation parapatric speciation
R_3_01 Verified Biology & Evolution

R_3_01 — Epigenetics and Ancestral Memory

Epigenetics — heritable changes in gene expression WITHOUT changes to the DNA sequence — has revolutionized biology over the past two decades. Your genes are the hardware; epigenetics is the software that determines whic

epigenetics DNA methylation histone modification transgenerational inheritance ancestral memory Lamarckism
R_3_05 Verified Biology & Evolution

R_3_05 — Coevolution — Arms Races, Mutualisms, and Red Queens

Coevolution — reciprocal evolutionary change between interacting species — is one of the most powerful engines of biological diversity. Leigh Van Valen's Red Queen hypothesis (1973) captured its essence: species must con

coevolution Red Queen hypothesis Van Valen arms race mutualism plant-pollinator
R_3_11 Verified Biology & Evolution

R_3_11 — Microevolution and Rapid Adaptation

Microevolution — changes in allele frequencies within populations over generations — is the fundamental engine of biological adaptation. Once assumed to operate too slowly to observe directly, research over the past 50 y

microevolution rapid adaptation contemporary evolution natural selection genetic drift gene flow
R_3_14 Verified Biology & Evolution

R_3_14 — Evolution of Aging and Senescence

Aging — the progressive decline in physiological function and increase in mortality rate with time — is one of evolution's deepest puzzles: why would natural selection, which optimizes fitness, permit organisms to deteri

aging senescence evolution mutation accumulation antagonistic pleiotropy disposable soma
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_3_06 Verified Biology & Evolution

R_3_06 — Altruism and Cooperation in Nature

Altruism — behavior that reduces the actor's fitness while increasing the recipient's — presents a fundamental puzzle for evolutionary theory: how can natural selection favor genes that reduce their bearer's reproduction

altruism cooperation kin selection Hamilton reciprocal altruism Trivers
R_3_20 Verified Biology & Evolution

R_3_20 — CRISPR & Gene Editing Technology

CRISPR-Cas9 is the most transformative biological technology since PCR, enabling precise, programmable editing of DNA in virtually any organism. The system was adapted from a bacterial immune defense mechanism first iden

CRISPR Cas9 gene editing genome engineering Jennifer Doudna Emmanuelle Charpentier
R_3_10 Verified Biology & Evolution

R_3_10 — Protein Evolution and Molecular Machines

Proteins are the molecular workhorses of life — catalyzing reactions, building structures, transporting cargo, transmitting signals, and defending against pathogens. They are also some of biology's most astonishing molec

protein evolution molecular machine protein folding enzyme kinesin myosin
R_3_04 Verified Biology & Evolution

R_3_04 — Sexual Selection — Mate Choice and Evolutionary Aesthetics

Sexual selection, first articulated by Charles Darwin in The Descent of Man, and Selection in Relation to Sex (1871), explains traits that enhance mating success rather than survival — from the peacock's extravagant tail

sexual selection Darwin mate choice peacock's tail Fisher's runaway Zahavi handicap principle
R_3_09 Verified Biology & Evolution

R_3_09 — Molecular Phylogenetics and Tree of Life

Molecular phylogenetics — reconstructing evolutionary relationships from DNA, RNA, and protein sequences — has revolutionized our understanding of the tree of life since Carl Woese's landmark 1977 discovery, using small-

phylogenetics molecular clock tree of life cladistics maximum likelihood Bayesian
R_3_03 Verified Biology & Evolution

R_3_03 — Evo-Devo: Evolutionary Developmental Biology

Evolutionary developmental biology ("evo-devo") reveals one of biology's most profound discoveries: the same small set of "toolkit" genes (Hox, Pax6, Sonic hedgehog, BMP, Wnt, etc.) controls body plan development across

evo-devo evolutionary developmental biology Hox genes homeobox toolkit genes deep homology
R_3_13 Verified Biology & Evolution

R_3_13 — Evolution of the Immune System

The immune system is one of evolution's most elaborate and costly creations — vertebrate adaptive immunity alone employs V(D)J recombination to generate over 10¹¹ distinct antibody specificities from fewer than 400 gene

immune system innate immunity adaptive immunity immunoglobulin T cell B cell