Adaptation of tobacco hornworms to the ingestion of nicotine

Radiometric, chromatographic, and spectrophotometric data show excretion and egestion of intact nicotine to be an explantion for the adaptation of the tobacco hornworm, Protoparce sexta (Johan.), to tobacco. There was no evidence for the metabolism of nicotine to less toxic metabolites after topical, injected, or ingested doses. Although nicotine was absorbed into the blood of the hornworm, a toxic dose did not appear to accumulate at the site of action.