The Very Hungry Caterpillar
The most interesting new technological innovations often come as a result of engineers looking at the natural world and seeing how it could be applied to their work. Some amazing examples are the insect proboscis which inspired micro-needle arrays used in skin grafts, photosynthetic technology based on plants, and the mirror-tube eyes of lobsters which have been harnessed to improve our microscopes.
However, sometimes a more up front approach yields the best results. Why simply copy nature when you can involve nature directly?
Plastics are becoming such a huge problem in the oceans and landfill sites of the world because they simply do not degrade over any useful timeframe. Plastic molecules are defined by very strong carbon-carbon bonds which are not broken down by fungi, bacteria, or any of the other organisms which usually work to degrade matter. Ultra-violet light can degrade plastic, but if there was enough of that getting through the atmosphere to destroy the abundant plastic in the world then we would have a whole different set of problems.
A Spanish scientist called Federica Bertocchini recently had a problem with her bees. A species of caterpillar known as a waxworm had infested her beehives and were rapidly eating through the wax which formed the structure of the bees’ home. She removed the waxworms and put them in a plastic bottle to give her time to clean the hives and save the bees. Then something curious happened. By the time she had finished cleaning the hives, the waxworms had eaten their way out.
Were they truly digesting the plastic or just destroying it? Bertocchini was unsure and decided to grind up some worms and spread them on plastic to make sure. As it turned out, even a worm paste was sufficient to eat through a standard polyethylene plastic bag in good time. This ability likely evolved by accident as a by-product of the ability to digest the beeswax in the beehives, but it could have important ramifications in the future.
We produce a lot of plastic. Of the almost 300 million tonnes of plastic released into the world every year, of which more than 8 million tonnes ends up in the oceans. More goes into the ground. This is an amount almost impossible to imagine and it ends up staying where it is put for so long that it might as well be forever as far as we are concerned.
Are these waxworms a solution to the potential problem? Probably not, but the idea behind them is interesting. Plastic pollution is becoming a more severe issue every year and we desperately need a solution. Even if everyone stopped dumping plastics tomorrow then there would still be hundreds of millions of tonnes in the world to deal with.
Instances like the waxworms found by Federica Betocchini may end up being most useful as a method to get this problem in the news more regularly and make people think about what is happening. There isn’t an easy solution, but every little helps...