César Hernández/CSIC
César Hernández/CSIC

These Caterpillars Chow Down on Plastic Bags

César Hernández/CSIC
César Hernández/CSIC

Remember The Very Hungry Caterpillar? He may have some serious real-life competition because scientists have discovered that a common caterpillar can eat and digest plastic. They published their findings in the journal Current Biology.

The wax worm is the larval form of the parasitic wax moth (Galleria mellonella), also known as the honeycomb moth. Adult moths chew their way into beehives, then lay their eggs, which will gorge themselves on honeycomb once they hatch. Because bees didn’t already have enough to deal with.

César Hernández/CSIC

Federica Bertocchini is a research fellow at the Institute of Biomedicine and Biotechnology of Cantabria in Spain. In her free time, she’s an amateur beekeeper. One day, she picked handfuls of yellow wax worms out of her hives and tossed them into plastic bags, destined for the trash. But a few hours later, the bags were riddled with holes. The prisoners had made a wiggly break for it.

Bertocchini was intrigued. She and her colleagues rounded up hundreds of wax worms and a bunch of shopping bags and put them all together. The larvae did not disappoint; one 100-worm test group perforated a plastic bag in 40 minutes. Left to their own bitey devices, the caterpillars ate through 92 milligrams of plastic, or three percent of a bag, in a half-day. At that rate, it would take them 17 days to make one bag disappear, which is substantially better than the 100 years it would take otherwise.

Anybody can eat plastic, but whether the worms were actually digesting it is another story. To find out, the researchers killed the larva, mashed them up into a paste, and smeared it on plastic film. Just 14 hours later, the caterpillar jam had eaten through 13 percent of the plastic.

Many questions remain. For starters, what exactly is digesting the shopping bags? It’s not clear if the ability to break down the plastic is inherent to the caterpillars, like a digestive enzyme, or if their guts are home to plastic-eating bacteria.

"If a single enzyme is responsible for this chemical process,” first author Paolo Bombelli of Cambridge said in a statement, “its reproduction on a large scale using biotechnological methods should be achievable. This discovery could be an important tool for helping to get rid of the polyethylene plastic waste accumulated in landfill sites and oceans.”

The researchers also noted that the caterpillars cannot live on shopping bags alone. “These animals don’t live on plastic,” Bertocchini told New Scientist. “They eat it to get out of it, or get to the food behind it. If in the future something evolves to exclusively eat plastic, I don’t know. So far it hasn’t happened.”

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This Self-Cloning Tick is Terrorizing More States
iStock
iStock

Few arachnids are as demonized in the summer months as ticks, the parasitic little nuisances that can spread disease in humans and pets. That's not likely to change now that there's a exotic new species that can not only self-replicate, but is also poised to attack animals like a colony of swarming fire ants.

This super-tick is Haemaphysalis longicornis, or the longhorned tick, native to East Asia and imported to the U.S. by unknown means. The first North American sighting took place in August 2017 in New Jersey when a farmer walked into a county health office covered in nearly 1000 ticks after shearing a pet sheep that had been infested. The insect was then spotted in Virginia, West Virginia, and Arkansas, with caution advised in Maryland. As of this week, it’s now a confirmed resident of North Carolina, The Charlotte Observer reports.

H. longicornis invites more dread than a conventional tick for several reasons. It can “clone” itself, with females laying up to 2000 genetically identical eggs without any assistance from a male, a process called parthenogenesis. Reproduction is faster, with offspring appearing in just six months compared to two years for common deer ticks. It’s also an aggressive biter, nibbling on any animal flesh it can latch on to, and is able to transfer a host of diseases in the process—some of them fatal. In addition to Lyme, longhorned ticks can transmit the flu-like ehrlichiosis bacteria and the rare Powassan virus, which can cause brain inflammation.

The news isn’t much better for livestock. Given enough opportunity, the ticks can siphon enough blood from an animal to kill it, a process known as exsanguination. The attack can become so concentrated that pets have been spotted with ticks hanging from them like bunches of grapes.

New Jersey officials have confirmed the tick has survived the winter by burrowing underground, a somewhat ominous sign that the invasive species might be durable enough to become a widespread problem. Experts recommend taking all the regular precautions, including wearing long pants when outdoors, using repellent, and examining yourself and your pets for ticks. While the longhorned tick hadn’t yet displayed a taste for human flesh, it’s better to be safe than sorry. As for the sheep: following a chemical treatment, she made a full recovery.

[h/t Charlotte Observer]

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Courtesy of Kari Kaunisto/Biodiversity Unit of the University of Turku
This Super-Stinger Wasp Was Just Discovered in the Amazon
Courtesy of Kari Kaunisto/Biodiversity Unit of the University of Turku
Courtesy of Kari Kaunisto/Biodiversity Unit of the University of Turku

Deserved or not, the Amazon has developed a reputation for hosting animals, insects, and other creatures that appear to exist solely to terrify humans. And everywhere in the world, you’ll find parasitic organisms that thrive when they siphon blood or other resources from hosts.

A new entrant has emerged in both of these charts: Calistoga crassicaudata, a wasp recently discovered in the Amazon that sports a stinger roughly half the length of its 9.8-millimeter-long body. The insect may as well come out of the workshop of Alien designer H.R. Giger: Its methodology is to impale prey with the stinger, paralyzing it, and then depositing eggs inside so they can hatch later. The hatching usually causes the host—typically a spider—to burst open and die in agony as C. crassicaudata laughs maniacally. Metaphorically speaking.

Researchers from the University of Turku, Finland, made the discovery between the Andes and the Amazonian lowland rainforest and reported it in the journal Zootaxa. The new species appears to be amazing wasp experts by the sheer magnitude of its built-in spear, also called an ovipositor, that delivers both venom and the female's eggs.

"I have studied tropical parasitoid wasps for a long time, but I have never seen anything like it," entomologist and co-author Ilari E. Sääksjärvi said in a statement. "It looks like a fierce weapon."

The good news? It’s not really strong enough to pierce human skin, so should you find yourself in its vicinity, you probably don't need to worry. Instead, worry more about the common paper wasp, which has a barbed stinger, takes only 0.5 seconds to impale you, and can retain its stinger to continue its assault.

[h/t LiveScience]

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