The Indian Express (Delhi Edition)
An escape from a shopping bag triggers an idea
Plastic-eating caterpillars could save the planet
MOST SCIENTIFIC research follows a logical progression, with one experiment following up on the findings of another. Every now and then, however, serendipity plays a part. Such is the case with a paper just published in Current Biology, which reveals to the world a moth capable of chewing up plastic.
The experiment behind the paper was inspired when Federica Bertocchini, an amateur beekeeper who is also a biologist at Cantabria University, in Spain, noticed caterpillars chewing holes through the wax in some of her hives and lapping up the honey. To identify them, she took some home in a plastic shopping bag. But when, a few hours later, she got around to looking at her captives she found the bag was full of holes and the caterpillars were roaming around her house.
After rounding them up, she identified them as larvae of the greater wax moth, a well-known pest of bee hives. On considering their escape from their shopping-bag prison, though, she wondered whether they might somehow be put to work as garbagedisposal agents.
Past attempts to use living organisms to get rid of plastics have not gone well. Even the most promising species, a bacterium called Nocardia asteroides, takes more than six months to obliterate a film of plastic a mere half millimetre thick. Judging by the job they had done on her bag, Dr Bertocchini suspected wax-moth caterpillars would perform much better than that.
To test this idea, she teamed up with Paolo Bombelli and Christopher Howe, two biochemists at Cambridge University. Dr Bombelli and Dr Howe pointed out that, like beeswax, many plastics are held together by methylene bridges (structures that consist of one carbon and two hydrogen atoms, with the carbon also linked to two other atoms). Few organisms have enzymes that can break such bridges, which is why these plastics are not normally biodegradable. The team suspected wax moths had cracked the problem.
One of the most persistent constituents of rubbish dumps is polyethylene, which is composed entirely of methylene bridges linked to one another. So it was on polyethylene that the trio concentrated. When they put wax-moth caterpillars onto the sort of film it had taken Nocardia asteroides half a year to deal with, they found that holes appeared in it within 40 minutes.
On closer examination, Dr Bertocchini and her colleagues discovered that their caterpillars each ate an average of 2.2 holes, three millimetres across, every hour, in the plastic film. A follow-up test found that a caterpillar took about 12 hours to consume a milligram of shopping bag. Such bags weigh about three grams, so 100 larvae might, if they spent half their lives eating, consume one in a month.
Whether releasing wax moths on the world’s surplus plastic really is sensible is not yet clear. For one thing, it has not been established whether the caterpillars gain nutritional value from the plastics they eat, as well as being able to digest them. If they do not, their lives as garbage-disposal operatives are likely to be short—and, even if they do, they will need other nutrients to thrive and grow. Another question is the composition of their faeces. If these turn out to be toxic, then there will be little point in pursuing the matter. Regardless of this, though, the discovery that wax-moth larvae can eat plastic is intriguing. Even if the moths themselves are not the answer to the problem of plastic waste, some other animal out there might be. summer to attack Hillary Clinton.
Even if Mr Pompeo’s designation of Wikileaks is accurate—and Susan Hennessey, managing editor of the Lawfare blog, thinks it may be—it may not provide a path to prosecution. But Ms Hennessey says an indictment might be possible under the Espionage Act, or laws governing theft of government property and computer abuse.
Chelsea Manning, the army intelligence analyst jailed for providing Wikileaks with a huge dump of classified material in 2010, was indicted under all three laws, though her sentence was commuted by Barack Obama before he left office. It appears that Mr Assange may have both incited Mr Manning (as he then was) to commit his crimes, and helped to facilitate them. If so, says Ms Hennessey, it might be fairly easy in purely legal terms to bring a conspiracy charge against Mr Assange.
This raises the question of why the Obama administration, not known for its tolerance of leaks, decided to stay its hand when it came to Mr Assange.
The reason was the difficulty of distinguishing Wikileaks’ activities from investigative journalism, which is protected by the bit of the First Amendment covering freedom of the press. Mr Obama was far from convinced that Wikileaks and Mr Assange did merit such protection, but was troubled about where a prosecution might go politically.
Mr Trump’s intense hostility towards the “mainstream media”, for what he perceives as its bias against him, means that he is unlikely to feel any such compunction. The overlap between what Wikileaks and traditional media organisations do has also become increasingly blurred. News outlets such as the New York Times and the Washington Post have introduced Securedrop, which describes itself as “an open-source whistleblower submission system that media organisations can use to securely accept documents from and communicate with anonymous sources.”
Given that both newspapers published the best bits of the material Wikileaks ran from the DNC hack, it must be assumed that if Russian intelligence agents had opted to provide it to them via Securedrop, they would happily have used it. They know that if they do not publish such material, there are plenty of rivals who will.
Ms Hennessey argues that there is still a vital difference between Wikileaks and, say, the New York Times. The Times edits and checks; its motives are different; it is not linked to hostile intelligence agencies. Such distinctions may not trouble Mr Sessions but, as Mr Trump has found, the courts do not always do his bidding.
It has not been established whether the caterpillars gain nutritional value from the plastics they eat, as well as being able to digest them. If they do not, their lives as garbagedisposal operatives are likely to be short—and, even if they do, they will need other nutrients to thrive and grow