The TC-Battle and a Conditional Exit

Escalation without end, or a durable truce by integration

Panel A. Coercion: escalation without end Six numbered steps alternate between E. coli actions (gold boxes, left) and responses by the strictly lytic T4 phage (red boxes, right), joined by zigzag arrows. A dashed return loop runs from step 6 back to step 1 and is labeled no stable equilibrium. A Coercion: escalation without end E. coli action (left) T4 phage response (right) no stable equilibrium 1. E. coli cuts foreign DNA, marks its own 2. T4 disguises its DNA (modified bases) 3. E. coli cuts modified DNA too 4. T4 adds anti- restriction proteins 5. E. coli shifts recognition sites 6. T4 evolves new DNA disguises
other phages
Panel B. Lysogeny: coordination by integration Phage lambda's DNA integrates into the E. coli chromosome as a prophage, so both lineages persist while the local arms race is suspended. The lysogenic state is highly stable and remains reversible: a durable, conditional truce. B Lysogeny: coordination by integration E. coli bacterial chromosome prophage: integrated λ DNA phage λ ✓ Both lineages persist ✓ Local arms race suspended ✓ State remains reversible A durable, conditional truce

Escalation has no resting state; integration does.

The TC-Battle and a conditional exit. (A) Coercive control produces an escalating arms race with no stable equilibrium. (B) T4 is strictly lytic. Bacteriophage λ can enter lysogeny, integrating into the host chromosome so both lineages persist in a highly stable state that can return to lysis. After Hofstadter (1979, pp. 532–536); lambda-state qualification from Little and Michalowski (2010).