39. Can temperature modulation slow aging?

Lowering temperature can extend lifespan within a species by slowing reaction kinetics, reducing some forms of damage production and activating stress response systems, as shown in model organisms, especially invertebrates. However, across mammals, lifespan does not simply scale with temperature because evolution has already built compensatory protection into long-lived and/or high-temperature lineages (humans, birds, many whales). This makes temperature a useful example for the difference between within-species plasticity and across-species optimization: what looks like a causal regulator in the lab becomes an evolved baseline in nature. A practical implication is that cross-species biomarkers may be improved if lifespan is modeled together with temperature (and other covariates) rather than alone.