Foul-Breathed Caterpillar Survives Thanks to Nicotine
The tobacco hornworm Manduca sexta emits nicotine-laden bad breath in order to ward off ravenous wolf spiders.
While most humans hooked on nicotine struggle to kick the habit, there’s one desert creature that actually thrives thanks to its healthy consumption of the drug.
The tobacco hornworm, scientifically known as Manduca sexta, devours coyote tobacco plants all day long and consumes more than a milligram of nicotine, or roughly the equivalent of one cigarette’s worth of the addictive drug. Researchers at the Max Planck Institute for Chemical Ecology have concluded that the hornworm’s immunity to nicotine allows it to consume large quantities, which in turn gives the caterpillar “defensive halitosis,” or bad breath, that it uses to fend off ravenous wolf spiders.
Senior author and biochemist Ian Baldwin led his team in conducting a series of experiments that involved starving individual wolf spiders for 24 hours and then placing hornworms loaded with nicotine into the same cup. Despite the spiders’ overwhelming hunger, they unequivocally refused to eat the caterpillars. Conversely, the wolf spiders immediately devoured other non-nicotine laden prey when placed inside the cup. "Spiders usually assess their prey after capture by tapping it with chemosensory endowed legs and palps," the study said. "Wolf spiders were clearly rejecting nicotine-fed larvae before penetrating their prey with their mandibles to inject their mixture of digestive enzymes and poisons."