Professors use whale earwax to reconstruct whale stress levels spanning 150 years. Wartime activities such as under water detonation, naval battles including ships, planes and submarines, contributed to increase cortisol concentrations during this period of reduced whaling.

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Professors use whale earwax to reconstruct whale stress levels spanning 150 years. Wartime activities such as under water detonation, naval battles including ships, planes and submarines, contributed to increase cortisol concentrations during this period of reduced whaling.