Chapter 13: Archaea: Life at the Extremes of Deep Time

Archaea biology instantiates the persistence sector. Extremophiles—thermal (>100^∘C at hydrothermal vents), halophilic (Dead Sea), acidophilic (pH < 2), radioresistant—represent the oldest lineage, closest to the Last Universal Common Ancestor. The α-orbit’s temporal invariance manifests in minimal genome change, metabolic conservatism, and extremophile robustness across deep time.