# Double Helix
> **Machine-Evolution Nexus:** [[articles/Digital Darwinism and the Invisible World of Machine Evolution|Digital Darwinism and the Invisible World of Machine Evolution]] places this concept within the history and governance of substrate-independent evolution.
**Domain:** Molecular Biology / History
**Doc Type:** Canonical Wiki Node
**Maturity:** Developed
## Definition
The double helix is the paired, antiparallel structure of DNA in which complementary bases enable stable storage and templated copying.
## Machine-Evolution Context
Its 1953 description made biological hereditary architecture legible in the same season Barricelli was running artificial evolutionary populations at the IAS.
## Continuity and Evidence Boundary
The model depended on experimental evidence, especially X-ray diffraction, and should not be reduced to a two-person discovery story.
## Relationships
[[wiki/DNA|DNA]], [[wiki/Rosalind Franklin|Rosalind Franklin]], [[wiki/Maurice Wilkins|Maurice Wilkins]], [[wiki/X-ray Diffraction|X-ray Diffraction]]
## Sources / Provenance
- Watson and Crick, _Nature_ 171 (1953); Franklin and Gosling, _Nature_ 171 (1953).