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2017 has been an eventful year, so as it comes to a close we'd like to look back at some of its most superlative science.

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Wax worms


Hottest year
2017 has been an amazing year for science.

From neutron star collisions and potentially habitable planets to birds that whistle alarm signals as they fly, we have covered a lot of groundbreaking science news this year. But before we usher in 2018, we here at Scishow want to take a moment to look back on our favorite superlatives of the year: the toughest, biggest, and hottest science of 2017.

First up is the award for 2017's toughest animal on the planet— or at least, the toughest stomach. In a paper published in Current Biology in April 2017, researchers announced that they discovered a type of pesky caterpillar that can easily chow down on a material most other species cannot stomach: plastic. Plastic waste has become an environmental disaster, and one of the worst offenders is a plastic called polyethylene, or PE, which accounts for about 40% of plastic products we make.

It’s the type of plastic in things like plastic bags. Part of what makes polyethylene so useful is that it’s one of the most stable plastics around. It’s a simple chain of carbon and hydrogen, which leaves no weak points where it can start to break down.

But that also means it sticks around for centuries. Scientists got all excited when they found bacteria that can break down PE in mere months. But that’s nothing compared to what wax worm moth caterpillars can do.

Wax worms are so named because they eat honeycombs. They’re the bane of bees and beekeepers worldwide. But when a scientist and amateur beekeeper in Spain tossed some wax worms she’d dug out of her hives in a plastic bag to dispose of them, she discovered something remarkable.

They chewed holes in the plastic. Further investigation revealed that these caterpillars don’t just tear the plastic into little pieces— they’re actually able to break down polyethylene in a matter of minutes. Not weeks, not months—minutes.

Something in the worms’ stomachs or saliva can chop PE into smaller molecules of ethylene glycol, which degrades much more readily because it contains oxygen. Scientists aren’t sure how they do this on the molecular level, but they’re working on figuring it out so maybe they can replicate that process. That way, maybe we can figure out a chemical way to break down plastic trash without having to, like, just dump armies of tiny caterpillars onto it.

Our next superlative is biggest— as in, “whoa, okay, that is the biggest dinosaur ever.” Scientists have actually known about this dino for years, ever since a shepherd in Patagonia literally stumbled across the fossil in a field in 2012 and called in the experts. But, nothing is officially official until it’s peer reviewed, and the species’ description and name were finally published this August in the Proceedings of the Royal Society B. It’s called Patagotitan mayorum and it belonged to a group of sauropods— dinosaurs with long necks and tails, thick legs, and small heads— called “titanosaurs.” And truly, it lives up to that name.

When paleontologists dug it up, they found what’s considered a fairly complete skeleton— leg and arm bones, hip bones, ribs, and vertebrae. And it was pretty obvious that this dinosaur was bigger than anything we’d ever seen before. The femur alone was 2.4 meters long.

If my femur were 2.4 meters long, I would be more than 8 meters tall. That would be awesome. I’d be like, “What’s up, guys?” Based on the bones, paleontologists estimate that P. mayorum was about 37 meters long and weighed around 62 metric tons, or as much as about 12 African elephants, making it the heaviest animal to ever walk on land.

So it’s massive. Huge. Like, mind-numbingly huge.

Along with some other gigantic sauropods we’ve discovered, P. mayorum sort of defies physiological physics because it’s just too big. Paleontologists are hoping that studying it will help us figure out how those giant animals could have possibly even existed. So there have been some cool studies published this year!

Unfortunately, though, we need to talk about something … not so cool. Our last superlative is hottest, for the fact that 2017 will probably turn out to be the hottest non-El Niño year on record. And it’s on course to be among the top three hottest years overall.

El Niño is a weather pattern that happens when ocean currents shift in the Pacific Ocean, pushing warm water eastward towards South America. It causes local and global changes in weather patterns. And it tends to make everything warmer on average, which is why most of the hottest years ever were El Niño years.

Climate scientists can get an idea of the relative warmth or coolness of years by averaging temperature readings from long-term monitoring sites all around the world. In 2014, without the help of El Niño, that global average temperature rose to 14.64 degrees Celsius, a full 0.74 degrees hotter than the average of the entire 20th century. Then in 2015, El Niño struck and we ended up with two of the hottest years ever recorded. 2016 was nearly a full degree hotter than the last century.

But now, even though this year isn’t an El Niño year, scientists with the United States National Oceanic and Atmospheric Administration say 2017 will likely rank as either the 2nd or 3rd hottest year ever, based on the temperatures we’ve been seeing. Without the effects of an El Niño complicating things, this year’s hotness is a clear example of just how much the planet is warming. And the heat has been cooking up some terrible stuff.

This year, we’ve seen an increase in storm surge severity, coral bleaching on the Great Barrier Reef, and record low sea ice coverage in the Arctic Circle. Being the hottest might be great for movies or people, but not great for years … or planets. At least 2017 also had plastic-eating caterpillars and humongous dinosaurs.

Those are great. And here’s hoping 2018 provides even more exciting superlatives to share. Thanks for watching, and thank you especially to all of our patrons on Patreon who make this available for free for everyone.

Without you, we would not be able to geek out about the toughest, biggest, hottest, most awesomest science all year long. So if we gave you a superlative, we would have to say that you are the wonderfulest! If you want to join those wonderfulest people and pledge your support, you can do so at