Irish elk vanished just as climate change degraded food quality, straining weapon-rebuild costs.

Evidence

The time when Irish elk disappear coincides precisely with a period of rapid climate change called β€œthe Younger Dryas.” This would have lowered the quality of available food and made it even more difficult for males to replenish the calcium and phosphorus cost of their weapons. β€” Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 320

Categorization

  • XREF: Parallels human arms races where regime change in resource availability crashes the losing side; echoes the fallow deer in Phoenix Park dynamic.
  • SEED: Essay angle: How environmental shocks convert peacetime military over-investment into existential catastrophe β€” the Irish elk as metaphor.