bio

Acclimatization

The reversible adjustments a body makes within its own lifetime to cope with a hard environment: over hours, weeks, or seasons. A spleen learns to squeeze harder after days of repeated diving; the body generates more heat under sustained cold immersion; red cells rise at altitude. What defines this tier is not that it appears but that it goes away: when the Haenyeo divers of Jeju adopted neoprene suits in the 1970s, the elevated winter metabolism they had carried for generations vanished within two or three years. That disappearance is the proof it was never in the genes.