2015 was an amazing year for science, but it was also a year for some amazingly overhyped science.
We put our hearts ahead of our data when speculating about advanced extraterrestrial civilizations. We so wanted to believe that a looming ice age would save us from global warming. And we were horrified to learn that the internet's favourite meat product might cause cancer, along with everything else in the goddamn universe.
Here are the most overhyped scientific discoveries of 2015, in all their glory.
The So-Called Alien Megastructure
It isn't an overhyped scientific discoveries list without some wild speculation about extraterrestrials, and 2015 did not disappoint. If you weren't familiar with the term "alien megastructure" before, you certainly are now.
The alien hullabaloo started in early October, when astronomers announced the discovery of KIC 8462852, a weird star in the Kepler database that flickers aperiodically, its brightness sometimes dropping by as much as 20%. It's certainly not a transiting planet, but it doesn't look like anything else we've seen, either. Still, nobody outside of the astro community would have given a rat's arse about the cosmic oddity if SETI researchers hadn't made this humble suggestion: Perhaps the star was being occluded by a giant, alien construction project, a la Dyson sphere.
The citizens of planet Earth worked themselves into a rabid frenzy over the idea, to the point that Neil deGrasse Tyson had to go on late night TV and tell us all to calm the hell down. SETI astronomers capitalised on the momentum, mobilizing state-of-the-art observatories to scour KIC 8462852's cosmic neighbourhood for the radio signals and laser pulses that would lend credence to the wild idea. They found not a single fingerprint.
The latest thinking is that KIC 8462852 is probably being occluded by a swarm of comets -- BORING -- but I'm personally holding out hope that somebody follows up on the giant space walrus idea.
Image: Artist's representation of a Dyson sphere, crumbling like the alien megastructure hypothesis, via Danielle Futselaar/SETI International
Earlier this fall, the world was confronted with some rather unsettling news: bacon, along with other processed meats including hot dogs and ham, is carcinogenic, according to a new scientific paper which evaluated over 800 studies for links between processed or red meat intake and cancer. Unfortunately, many media reports took the "bacon cancer" soundbite and ran with it, leaving readers to imagine that consuming bacon is similar to touching nuclear waste. It's not.
There are a few reasons we shouldn't panic about this revelation, as Gizmodo's George Dvorsky lays out in detail. First and foremost, while the new study did find a real statistical correlation between processed meat consumption and bowel cancer, many subsequent reports failed to identify the magnitude of risk. That turns out to be fairly small. As you might expect, it increases slightly with the amount of processed meat consumed.
To make matters even more confusing, because processed meat is now classified as a Group 1 carcinogen, some articles suggested eating bacon is as bad as smoking cigarettes or asbestos exposure -- other Group 1 carcinogens. But again, the Group 1 label has nothing to do with risk magnitude, only the strength of scientific evidence linking a substance to cancer. About 34,000 cancer deaths each year are associated with a diet high in processed meat. Smoking, on the other hand, leads to about a million deaths a year.
If there's a takeaway in all of this, it's that it's probably a good idea to limit your consumption of processed meat -- health professionals have been suggesting this for years anyway -- and to always be sceptical when reading about new linkages between certain foods and cancer. Because really, when you get down to it, pretty much anything can cause cancer.
Image via Cookbookman/Flickr
It was in 2014 that we first heard whispers of NASA's EM Drive, an "impossible" engine that could (in theory) accelerate objects (our future spacecraft) to near relativistic speeds without the use of any propellant, simply by bouncing microwaves around a waveguide. The laboratory "evidence" for the physics-defying engine might have been nothing more than analytical error -- or, as one expert put it, bullshit -- but that didn't stop people from continuing to scour NASA engineering forums for additional affirmation of the science fictional technology in 2015.
EM Drive prototype by NASA/Eagleworks, via NASA Spaceflight Forum
Lo and behold, the sleuths of the internet found some. Apparently, the engineers working on the EM Drive decided to address some of the sceptic's concerns head-on this year, by re-running their experiments in a closed vacuum to ensure the thrust they were measuring wasn't caused by environmental noise. And it so happens, new Em Drive tests in noise-free conditions failed to falsify the original results. That is, the researchers had apparently produced a minuscule amount of thrust without any propellant.
Once again, media reports made it sound like NASA was on the brink of unveiling an intergalactic transport system.
The real problem with the EM drive isn't the scientists. It isn't even the science. The problem is that a) NASA hasn't claimed that the system works; b) there have been no peer-reviewed papers on the subject; and c) as far as we can tell, all evidence for the physics-defying machine comes from a handful of short-term experiments. This is a story of scientists caught in the act of tinkering by people who want Star Trek to happen now.
Image via Star Trek Wiki
An Ice Age in 2030?
You know what would really save us from this global warming mess we've gotten ourselves into? An ice age! And earlier this year, it seemed like our prayers were answered, when a new astronomy study suggested that the sun is heading for a period of extremely low solar output -- a so called 'Maunder minimum.' A press release accompanying the study explained that predictions from the astronomers' new models "suggest that solar activity will fall by 60-per cent during the 2030s to conditions last seen during the 'mini ice age' that began in 1645."
This led to some confusion.
Even if it's true that the sun's output is on the verge of declining to levels not seen in over 350 years -- and the likelihood of that varies greatly from study to study -- it's misleading to say we're on the brink of an ice age. The Little Ice Age saw temperatures drop by about 1º C, whereas real ice ages are characterised by global average temperatures 5º C cooler than today.
It's also misleading to insinuate that the 17th century Maunder minimum even caused the Little Ice Age. As astronomer Jim Wild explained earlier this year, the Little Ice Age began over a century before the start of the Maunder minimum and continued long after it was over. People still aren't sure what led to the cold snap -- the leading suspect is currently volcanic activity -- or if it was even a global phenomenon.
Finally, the overwhelming consensus of the world's climate scientists is that the influence of solar variability on climate is dwarfed by the impact of increased CO2 in the atmosphere. Indeed, many calculations suggest that a "grand solar minimum" would at best offset a few years' worth of the warming that's being caused by human carbon emissions.
Simply put, we cannot bank on the vagaries of the sun to save our collective arses this century.
Image: London policemen on ice skates on the frozen River Thames circa 1900, via Getty
The Tardigrade's Seriously Weird Genome
Tardigrades -- those weird, wonderful, microscopic poncho bears that're virtually indestructible -- got even weirder this year, when researchers at the University of North Carolina Chapel Hill decided to sequence the tardigrade genome. Astonishingly, the team discovered that a full sixth of the animal's DNA was not animal DNA at all: it was from plants, fungi, bacteria, and viruses. Nobody had ever seen anything like it before, which in hindsight, maybe should have been a red flag.
As Annalee Newitz explained last month, the authors suggested the tardigrade's patchwork genetic code was acquired via horizontal gene transfer, and that this could be related to the animal's unique stress response:
When tardigrades are desiccated, their DNA breaks into pieces. Any organisms around them will also suffer the same fate. But when water returns to the tardigrade's environment, they re-hydrate and return to life. As they re-hydrate, their cell walls become porous and leaky, and fragments of DNA from the desiccated organisms around them can flow inside and merge with the animal's rejuvenating DNA.
Furthermore, the UNC authors speculated that the tardigrade's borrowed genes may help the animal withstand everything from boiling water to the vacuum of space. It's a fascinating story about an amazing organism, so it's no surprise the paper got a lot of pickup. But it's not at all clear that the conclusions are sound.
Indeed, less than one week after the UNC Chapel Hill version of the tardigrade genome was published in PNAS, another lab at the University of Edinburgh posted a pre-print of their tardigrade genome analysis, which painted an entirely different picture. Edinburgh researchers found very little evidence for horizontal gene transfer -- as few as 36 genes, compared with the 6,600 reported by UNC Chapel Hill.
How could this be? One possibility is that many of the sequences the UNC team called bonafide tardigrade genes were, in fact, microbial contamination. As science journalist Ed Yong explains over at The Atlantic, the Edinburgh team carefully cleaned up their data to remove many sequences that were only present in trace quantities, which the scientists presumed to be contaminants. "I want to believe that massive HGT happened, because it would be an awesome story," Mark Baltrus, lead author of the Edinburgh study told The Atlantic. "But the problem is that extraordinary claims require extraordinary evidence."
On the bright side, what could have become a bitter dispute between rival labs turned into a fruitful collaboration: the two teams are now sharing their data in an attempt to reconcile their disparate findings.
Science is a messy, error-fraught business -- and if we think we're doing it all right the first time, chances are we're wrong.
Image via Sinclair Stammers