Caterpillars that blow nicotine at their enemy; hornworm, a species that eats tobacco plants without seeming to be bothered by the nicotine in the leaves; scientists wondered if the hornworm might be weaponising nicotine

Caterpillars that blow nicotine at their enemy

Jan 4th 2014 | From the print edition

THE blue caterpillar in “Alice’s Adventures in Wonderland” had a hookah habit and the white rabbit kept looking at his pocket watch. But whereas rabbits are not obsessed about being late, some caterpillars, it seems, really do have a fondness for blowing nicotine at those who annoy them.

The caterpillar in question is the hornworm, a species that eats tobacco plants without seeming to be bothered by the nicotine in the leaves. Since nicotine can work as a natural insecticide, this has led many to wonder what the caterpillars do with the toxins they consume. One clue is that some caterpillars use toxins they collect as weapons—the eastern tent caterpillar is famous for spitting hydrogen cyanide gathered from the plants it eats at its enemies. A team led by Ian Baldwin at the Max Planck Institute for Chemical Ecology in Jena, Germany, wondered if the hornworm might be weaponising nicotine.Dr Baldwin and his colleagues set up an experiment in which hornworm caterpillars were placed in fields filled with either ordinary tobacco plants or ones genetically modified not to produce nicotine. Also roaming these plots were wolf spiders, natural predators of the caterpillars. Would the caterpillars in the nicotine-free fields be rendered more vulnerable to the spiders?

They were, as the team report this week in Proceedings of the National Academy of Sciences. Among the nicotine-containing tobacco, 75% of the caterpillars survived each night of spider attacks, but only half did so in the nicotine-free fields. To discover more Dr Baldwin and his colleagues took some of the caterpillars and silenced a gene that moves nicotine from their gut into their blood. This would prevent nicotine being exhaled through the spiracles on their body and make them release considerably more nicotine into their faeces.

Close examination inside gas-controlled chambers revealed that, while ordinary caterpillars fed ordinary tobacco released nicotine when they exhaled, the gene-silenced caterpillars only defecated it. So, even when they ate tobacco containing nicotine, the caterpillars with the silenced gene still ended up in the jaws of wolf spiders over three times more than those that had not had their gene silenced.

When air containing nicotine was taken from an enclosure of non-genetically modified caterpillars eating ordinary tobacco and put into a container of caterpillars with the silenced gene, the wolf spider attacks dropped by 64%. So, for the hornworm at least, it looks like the case is proved. As for Lewis Carroll’s blue caterpillar, no one is quite sure what it was smoking in its hookah.

About bambooinnovator
Kee Koon Boon (“KB”) is the co-founder and director of HERO Investment Management which provides specialized fund management and investment advisory services to the ARCHEA Asia HERO Innovators Fund (www.heroinnovator.com), the only Asian SMID-cap tech-focused fund in the industry. KB is an internationally featured investor rooted in the principles of value investing for over a decade as a fund manager and analyst in the Asian capital markets who started his career at a boutique hedge fund in Singapore where he was with the firm since 2002 and was also part of the core investment committee in significantly outperforming the index in the 10-year-plus-old flagship Asian fund. He was also the portfolio manager for Asia-Pacific equities at Korea’s largest mutual fund company. Prior to setting up the H.E.R.O. Innovators Fund, KB was the Chief Investment Officer & CEO of a Singapore Registered Fund Management Company (RFMC) where he is responsible for listed Asian equity investments. KB had taught accounting at the Singapore Management University (SMU) as a faculty member and also pioneered the 15-week course on Accounting Fraud in Asia as an official module at SMU. KB remains grateful and honored to be invited by Singapore’s financial regulator Monetary Authority of Singapore (MAS) to present to their top management team about implementing a world’s first fact-based forward-looking fraud detection framework to bring about benefits for the capital markets in Singapore and for the public and investment community. KB also served the community in sharing his insights in writing articles about value investing and corporate governance in the media that include Business Times, Straits Times, Jakarta Post, Manual of Ideas, Investopedia, TedXWallStreet. He had also presented in top investment, banking and finance conferences in America, Italy, Sydney, Cape Town, HK, China. He has trained CEOs, entrepreneurs, CFOs, management executives in business strategy & business model innovation in Singapore, HK and China.

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